bluuebunny/crossref_metadata_2025 huggingface dataset:
A clearinghouse for scientific and technical meetings: Organizational and operational problems
Authors: Baum Harry
Published: June 2007

There has been much interest expressed in the formation of a clearinghouse for scientific and technical meetings. In spite of this interest, no clearinghouse has been formed. Whether or not there is a valid need for the existence of such a clearinghouse has not been proven, but in this paper it is assumed that the need exists. Discussion of the organizational and operational problems involved follows. These problems include: (a) definition of area and level of coverage of the subject matter of any given meeting; (b) definition of the geographic area from which the meeting will draw its attendance; (c) definition of the area of interest of the clearinghouse in the face of difficulties imposed by mission‐ or project‐oriented meetings and other interdisciplinary meetings; (d) attaining comprehensive coverage in spite of the difficulties in obtaining inputs from the organizers of government classified and other closed meetings, as well as from the organizers of ad hoc meetings; and (e) the need to ensure that the organizers of meetings will make use of the clearinghouse. Solutions to these problems will not yield to a simple approach, but will be obtainable only on the basis of careful study of the structure and dynamics of the national and international scientific and technical meetings network.
The KWIC index concept: A retrospective view
Authors: Fischer Marguerite
Published: June 2007

This paper defines and describes the KWIC (keyword in context) index concept, providing a history of the concept and of its literature. It discusses variations of the index, such as the Bell Telephone Index, KWOC indexes, and the WADEX.

The paper discusses improvements and variations to the KWIC index, such as manipulation of the index line, variations of the code, addition of classification information, combination of author index and title index, and improvements of the type face. It also discusses improvements to the preparation of the KWIC indexes, such as improvement of titles and use of a thesaurus, and discusses improvement of the use of the KWIC index. The paper discusses the usage of the KWIC index and comments on the future of KWIC indexes and of the KWIC concept.
Characteristics and use of personal indexes maintained by scientists and engineers in one university
Authors: Jahoda G. , Hutchins Ronald D. , Galford Robert R.
Published: June 2007

Interviews with 75 graduate school faculty members in the science and engineering departments at Florida State University have revealed that 46 of the interviewed faculty members maintain personal indexes. The structure of these personal indexes, their size, rate of growth, frequency of use, physical form, and other characteristics are given and discussed.
State of the art of computers in commercial publishing
Authors: Markus John
Published: June 2007

Despite excessive glamorizing of the role of computers in publishing, truly economical applications are beginning to emerge. Many types of directories, indexes, cumulated bibliographies, and cumulated library book catalogs can today be put through a computer in less time and at less cost than for conventional typesetting. Examples of successful applications are given, after taking up one by one the many system design decisions that must be made in the areas of input hardware, computer hardware, computer software, and output hardware. Major attention is given to the proofreading problem, because line printers are still far from ideal for producing the equivalent of galley proofs.
Library catalogue production on small computers
Authors: Kilgour Frederick G.
Published: June 2007

The paper discusses the production of library catalogue cards, specifically treating the Columbia‐Harvard‐Yale Medical Libraries Computerization Project.

The Harvard Medical Library withdrew from the Project as of 30 June 1966.

A description is provided of the bibliographic data input, general computer processing, and various output modes. The paper, also, treats of error controls, human edit procedures, and the complexity and variety of present bibliographic organization in the context of computer manipulation.
A computer‐program system to facilitate the study of technical documents
Authors: Bobrow Daniel G. , Kain R. Y. , Raphael Bertram , Licklider J. C. R.
Published: June 2007

Symbiont is a computer‐and‐program system for use in research on computer‐aided study. It stores, retrieves, and displays documents and parts of documents. It “semi‐automates” the taking of verbatim notes. It facilitates the manipulation and intercomparison of graphs. And it conducts searches for passages of text that contain specified words or phrases. Experience with Symbiont and plans for its improvement are described.
Dictionary buildup and stability of word frequency in a specialized medical area
Authors: Long John M. , Barnhard Howard J. , Levy Gertrude C.
Published: June 2007

This is a report of word usage in radiological (x‐ray) patient records as found in a 5% sample of the annual case load at UAMC including 100,000 words. Records were taken exactly as dictated. The study is part of an effort to develop an IR system for patient data. The system “autocodes” (automatically stores) the physician's dictated findings and diagnoses in such a fashion that they can be retrieved again automatically.

Some of our findings approximate results reported in the literature. For example, the rate of introduction of new different words levels off to about 2,500 words when 40,000 to 50,000 words of text have been analyzed. However, unclassified words continue to occur at a significant level of almost 2% at the 100,000 word level, with a 1% noise level.

Attempts to establish the rank order of words beyond the first several hundred have failed because about 70% of the words appear to occur with such a low relative frequency (no more than one time in 10,000). Thus, establishing files by rank order appears impractical, even though filter lists (discard words) by rank groups (words with nearly the same relative frequency) are quite practical.

Additional data are presented and design implications are discussed.
Computer‐produced microfilm library catalog
Authors: Kozumplik W. A. , Lange R. T.
Published: June 2007

The philosophy, production, and cost‐effectiveness of a computer‐generated library catalog is described. This catalog is unique in that it utilizes direct computer to microfilm composition techniques, employing the Stromberg Carlson 4020. Cost, user acceptance, and by‐product capabilities are stressed.
A rationale for attacking information problems
Authors: Wall Eugene
Published: June 2007

The “systems” approach to information system problems is suggested, wherein problems arising from information origination, processing, and utilization—and alternative solutions to the problems—can be viewed as an entirety rather than piecemeal. Information utilization problems involve sociopolitical considerations (e.g., “wants” vs. “needs” of users), economic values of information, and the more objective considerations of timeliness, quality, and format requirements placed upon information services or products. Quality is encompassed by the factors of specificity, completeness, and relevance. Information processing is shown to consist of seven distinct “unit processes,” which may be combined in only nine different ways, thus defining nine possible types of information systems. The “unit processes” employed interact strongly with each other and with user requirements. Information origination—specifically the increasing ratio of “dross” to “ore”—is stated to be the single major information problem for which rational means of attack are not apparent at present.
Libraries and machines—A Review
Authors: Adkinson Burton W. , Stearns Charles M.
Published: June 2007

The application of computers to library operations is discussed in broad terms. Three phases in automation of libraries are identified: the mechanization of conventional operations such as bibliographical control processes and administrative monitoring systems; the automation of search processes based on subject matter; and the move toward new and different kinds of services that computer technology may make possible. We are in the second phase, and snagged by the difficulty experienced by computers dealing with natural language and subjective ambiguities. To move forward through phase two will require a better dialog capacity between man and machine than presently exists. Before progressing into the third phase a better identification of the purposes that our files of information are to serve will be needed.

Practical considerations affecting computer adoption by libraries are identified as: the need to stay in business during conversion to automated modes; the necessity for demonstrating in advance the economic advantages of conversion; the difficulty of proving in advance that conversion will meet real user needs; and the standardization and compatibility problems that will have to be solved to make the various automated libraries able to use one another's services efficiently.
A study of the use of materials circulated from an engineering library, March to May 1956
Authors: Pings Vern
Published: June 2007

The purpose of this study undertaken from March to May 1956 was to determine how an academic engineering library was used by two groups of users, the undergraduates and graduate students–faculty. The part of the study reported here is the result of a questionnaire given to the user at the time he charged out an item at the circulation desk to ascertain for what purpose he selected the item(s) and how he learned about it as a source of information. Variations in the reasons for selecting items changed during the three periods the data were collected. The undergraduates borrowed less for classroom work as the semester progressed, while the graduate‐faculty group borrowed increasingly for this reason. Supporting the conclusions of the other studies, the most important source for learning about an item was personal through recommendation; however, one of every four items charged out was discovered in browsing through the library's collection. From this study one can conclude that not only must librarians be acquainted with their users as individuals, but that the physical arrangement of library materials is an important factor in accessibility to information in an academic environment.
A general model of information transfer: Theme paper 1968 annual convention
Authors: Murdock John W. , Liston David M.
Published: June 2007

A general model of information transfer establishes a conceptual framework for contributed papers for the 1968 ADI Convention in Columbus, Ohio, October 20–24, 1968. The general model is an elaboration on the classic sender/channel/receiver model and presents a variety of alternative channels for information transfer including direct transfer, primary recorded media, archives, secondary recorded media, and information centers. Suggested areas for response in the form of contributed papers include costs, performance, benefits, functions, application of scientific and technical disciplines, research, vocabulary control, and language processing associated with information systems, science, and technology. A call for papers for the 1968 ADI Convention is included.
Computer usage in the development of a water resources thesaurus
Authors: Hersey David F. , Hammond William
Published: June 2007

This paper describes one method by which a thesaurus has been developed making extensive use of a computer to supplement the intellectual effort. The computer techniques incorporate several exceptionally useful innovations not previously disclosed in the open literature. The thesaurus which was developed is similar in convention and format to that recently adopted for Project LEX (4).
Information science: What is it?
Authors: Borko H.
Published: June 2007

In seeking a new sense of identity, we ask, in this article, the questions: What is information science? What does the information scientist do? Tentative answers to these questions are given in the hope of stimulating discussion that will help clarify the nature of our field and our work.
Air pollution technical information processing—the microthesaurus approach
Authors: Tancredi Samuel A. , Nichols Owen D.
Published: June 2007

The purpose of this report is to describe the microthesaurus approach to indexing technical literature, as used within the Air Pollution Technical Information Center (APTIC) of the National Center for Air Pollution Control (NSAPC). Using the Thesaurus of Air Pollution Terms as a base, a microthesaurus was constructed by dividing the field of air pollution and its effects into major categories such as Humans and Animals, Plants and Foods, Pollutants, Measurements, and others. These major categories were further divided to sub‐categories such as Respiratory Diseases, Suspended Particulates, and Materials Deterioration. Finally, the subcategories were reduced to very specific terms such as asthma, bronchitis, emphysema—all subordinate to Respiratory Diseases. Approximately 1,300 terms were arranged hierarchically on three display sheets with each term coded according to the number‐color scheme of a Jonkers Termatrex system. These sheets were subsequently used to deep‐index several thousand air pollution documents. It was concluded that the micro‐thesaurus approach provided the following: (1) consistency of indexing; (2) elimination of coding and spelling errors; (3) retrieval of both broad and highly specific information; and (4) adaptability to manual and mechanized systems.
A physician oriented method for clinical information retrieval
Authors: Smith Michael J. , Levy Richard P.
Published: June 2007

A system is described whereby a physician can, by use of a simple language, effectively search a large amount of active clinical patient data. The language, which is in everyday use has been found to be easily learnable. The language allows partitioning a file in a number of different ways, thus permitting the chronology of a patient's record to be a search parameter. The output from the search provides a count of the documents searched, the proportion that satisfy the search, and the identifying numbers of those documents which contain the desired information. At the option of the user, the output may be supplemented by all or part of those documents which met the requirements of the search.
Computer simulation of a small information system
Authors: Caras Gus J.
Published: June 2007

This paper illustrates how computer simulation techniques can be used to simulate information systems. A computer program for a small system was written in GPSS III (a special simulation language) and run in an IBM‐7090 Computer. The results obtained and the types of conclusions drawn are briefly discussed.
GAF document storage and retrieval system
Authors: Starke A. C. , Whaley F. R. , Carson E. C. , Thompson W. B.
Published: June 2007

The system is designed primarily for company reports but may include any documentary input. The following steps are involved in input: (1) Documents are scanned, selected, and subdivided (where necessary); (2) on a worksheet are entered a bibliographic description, a store address, and index descriptors and subdescriptors; index entries are chosen with the aid of a GAF Thesaurus structured to control synonymity, generic and other conceptual relationships; (3) document and worksheet are microfilmed for storage; (4) the worksheet contents are keyboarded for machine‐readable records, first on tape for IBM 1401, in the future on disc for a third‐generation computer. The input is punched cards at present, but more sophisticated input devices are under study. Computer programs comprise the Combined File Search (CFS) system (IBM 10.3.047) with several interface programs included. Document retrieval involves the following steps: (1) An inquirer from any one of the Company's units presents a Search Request Form using both narrative and descriptors chosen with the aid of the GAF Thesaurus; (2) the question is transformed at the center into a set of search descriptors and subdescriptors in appropriate logic statements involving AND, OR, and AND NOT logic, with the option of linking descriptors or truncating them to get word stems; the program has the option of printing out all or part of the master records for documents retrieved; (3) the inquirer reviews the index output and selects relevant addresses; (4) the addressed reports are located in the microfilm store at his location, reviewed, and prints made where needed.
Thesaurus development for a decentralized information network
Authors: Eller James L. , Panek Robert L.
Published: June 2007

A review is given of specialized requirements needed for the development of a controlled vocabulary for a decentralized information network composed of 18 subject‐oriented clearing houses in the field of education. The major elements of the review include initial development stages, appointment of an advisory group for terminology development, coordination requirements, and lexicographic procedures. Training and coordination related to thesaurus development in a decentralized information network are discussed. A computerized method for developing descriptor group displays is examined and illustrated.
A study of searching the eye research literature
Authors: Miller Russell R.
Published: June 2007

The paper is a report of most of the major findings of a study in searching the periodical eye research literature. Questions were collected from eye researchers and a selected group of these were searched in nine different secondary sources. Articles thought to be relevant were Xeroxed and sent to the eye researchers who subsequently rated the articles. Articles of eye research interest are found in a wide variety of journals, but a small number of journals carry a large proportion of the articles judged valuable by the eye researchers. Approximately a fourth of eye research articles are in foreign languages. Translations are not readily available. Despite a delay of more than 15 months between the original appearance of articles in journals and the mailing of photocopies, about half of the articles of interest to the researchers were not known to them previously. For extensive retrospective searches more than one secondary service must be used. Index Medicus and Excerpta Medica (Section 12) or Ophthalmic Literature would be good sources. MEDLARS demand searches were not shown to be clearly superior to manual searches of Index Medicus. Titles, abstracts, and full text were shown to be equally effective in permitting searchers to retrieve references that were subsequently rated as relevant by the researchers. A searcher with a background in ophthalmology was able to retrieve more articles of research interest than other non‐ophthalmologist searchers.
Using information in the life insurance business world
Authors: Cueto Manuel R.
Published: June 2007

Construction and maintenance of a large life‐insurance‐information system in the light of current equipment are described. The objectives, functions, organization of data, and the problems of operation of such a system from the viewpoint of the user and administrator are discussed.
Computer graphics: An assembly line for information
Authors: McConnell William A.
Published: June 2007

The growing disparity in productivity between manufacturing and engineering design activities suggests that “software” systems—in which information is organized to produce instructions—must adopt some of the disciplines that have been fruitful in the “hardware” systems—where materials are organized to create products. Developments at Ford toward measuring elements of the design task, detailed planning and organizing of the engineering process at its inception, and elimination or acceleration of the iterative process characteristic of the “scientific method” are discussed in this context. Particular attention is given to the importance of computer graphics and its use with a time‐shared computer system as communication and storage means—the beginnings of an “assembly line” for information.
The determination of legal facts and economic guideposts with respect to the dissemination of scientific and educational information as it is affected by copyright—A status report
Authors: Sophar Gerald J.
Published: June 2007

The study determines the amounts, kinds, source, and age of copyrighted materials copied by United States libraries and information centers. It also examines the “fair use” principle to see if the current copying practices do in fact conform to copyright law. More than one billion pages of copyrighted materials were copied by United States libraries in 1967, almost all as single copies. The librarian equates this practice with fair use despite the fact that there is nothing in copyright statute or the common law to justify this practice. Under current beliefs and practices single‐copy reproduction is not significantly affected or restricted by copyright law. Conclusions and recommendations based on the study are made.
Imprecision in indexing. Part II
Authors: Tinker John F.
Published: June 2007

By freeing indexers from the necessity of using standard language, and placing them only under the constraint of choosing descriptors from a short authority list to which they may freely add modifiers, a lucid and understandable index can be produced. Used in conjunction with the listing program and the display described, this approach produces a remarkably efficient index to a series of a few thousand related compounds. The consistency of use of terms on the authority list, expressed as an increase in the chance of retrieval, is improved, but not brought to perfection. The meaning of a given term to the various indexers, judged by their lack of agreement in applying it to the abstracts, remains imprecise. The listing programs and display can also be used to produce an index in a broad subject area. However, the utility of the index to a broad subject area will depend to a greater extent on the application of indexing policies and on an authority list that is less a dictionary and more a thesaurus which reflects these policies.
Automated control of a fast‐turnaround contractor—Subcontractor document management system
Authors: Komiske Patrick T. , Braunstein Albert A.
Published: June 2007

Automated Control of a Document Management System (ACDMS) was devised and implemented with the use of an IBM‐7094 information retrieval system in the Applied Physics Laboratory's computing center. The system provides management control in a timely manner for all documentation relevant to the Laboratory's subcontract with industry to construct satellites. Characteristically, the ACDMS has provided logging, processing, and control information for over 5,000 satellite drawings and more than 2,000 other documents and their continuing revisions that have flowed between the Laboratory and the subcontractor for over two years.
The use of simulation in studying information storage and retrieval systems
Authors: Baker Norman R. , Nance Richard E.
Published: June 2007

Previous applications of simulation to information storage and retrieval systems (ISRS) have been overly restrictive in their scope and have failed to consider the environment within which such systems operate. This paper considers the ISRS as a subsystem within a larger system which includes the users and the funders of the retrieval system. The three components form a closed‐loop information feedback system in which user response influences both the funding and operation of the ISRS as it attempts to satisfy user needs within a finite budget allocation. Reward‐cost theory provides the basis for describing user behavior. An industrial dynamics model has been developed to simulate ISRS/ user/funder behavior where a university departmental library is the ISRS component. The results which such an analysis can produce are discussed.
Retrieval of answer‐providing documents
Authors: O'Connor John
Published: June 2007

(I) Better understanding of subject document retrieval might result if different functions of subject document retrieval systems are studied separately. This paper is concerned with retrieval of documents, in response to a question, from which answers to that question can be inferred (“answer‐providing documents”). “Answer can be inferred from document” has many possible meanings, one of which must be selected (an “inference specification”). Inasmuch as scientists in a field sometimes disagree about the correctness of inferences, have somewhat different background knowledge, etc., any inference specification can only approximate scientific inference practices. Two sources of systematic knowledge of document‐statement inference practices in a scientific field are described. (II) If a content word occurs in a question, then it occurs in any answer to that question (with some apparently tractable exceptions). An indexing procedure based on that fact is described which would permit retrieval of all answer‐providing documents for a question. However, because the indexing is “nonrelational,” it could cause false retrievals as well. Various ways of dealing with such false retrievals are briefly indicated, and a study is sketched that would provide data for helping selection among them. Two special points concerning indexing for retrieval of answer‐providing documents are discussed separately.
Measures for the comparison of information retrieval systems
Authors: Pollock Stephen M.
Published: June 2007

A definite need exists for an absolute and uniform means of comparison and evaluation of certain characteristics of various information retrieval systems. This paper is concerned only with the system's ability to satisfy queries; the effort and time used, and their relative costs, are not considered. Some past procedures that have been used are reviewed and discussed, along with some of the difficulties that arise when these procedures are followed. We present some desirable characteristics for a meaningful measure of effectiveness, then analyze in detail one such measure that may be used to compare the retrieval capabilities of a large variety of systems. This measure, called the “normalized sliding ratio,” has a relation to the classical recall and precision ratios and may be looked on as a generalization of them.
The browser's retrieval game
Authors: Treu Siegried
Published: June 2007

A three‐mode game (procedure), applicable to time‐sharing information retrieval systems, is described in detail and demonstrated by limited experimental results. It is designed to offer the system user direct interaction with the system and a certain browsability through its information file. An association function is required to assign a level of association, based on co‐occurrence frequencies, to every pair of terms in the term vocabulary. The association level of a pair serves as indicator of in‐file presence or absence of the represented concept. The user starts with any single term(s) or term pair(s), “browses” through the available index term vocabulary “aisles” by means of a display console, and finally arrives at the game's objective: Either a query in terms of pair(s) of highly associated terms or the conclusion that the subject of interest is not represented. Formulating a query by coordinating only highly associated terms is expected to produce several advantages. It provides more specificity to query meaning while nevertheless insuring the retrieval of relevant items. It also prevents many false drops otherwise generated by erroneously coordinated index terms. The experimental results lend support to these expectations.
Statistical generation of a technical vocabulary
Authors: Stone Don C. , Rubinoff Morris
Published: June 2007

The results of an experiment in the use of statistical techniques for extracting a technical vocabulary from document texts are presented and discussed.
Interactive low‐dimensional human motion synthesis by combining motion models and PIK
Authors: Carvalho Schubert R. , Boulic Ronan , Thalmann Daniel
Published: July 2007

This paper explores the issue of interactive low‐dimensional human motion synthesis. We compare the performances of two motion models, i.e. Principal Components Analysis (PCA) or Probabilistic PCA (PPCA), for solving a constrained optimization problem within a low‐dimensional latent space. We use PCA or PPCA as a first step of preprocessing to reduce the dimensionality of the database to make it tractable, and to encapsulate only the essential aspects of a specific motion pattern. Interactive user control is provided by formulating a low‐dimensional optimization framework that uses a Prioritized Inverse Kinematics (PIK) strategy. The key insight of PIK is that the user can adjust a motion by adding constraints with different priorities. We demonstrate the robustness of our approach by synthesizing various styles of golf swing. This movement is challenging in the sense that it is highly coordinated and requires a great precision while moving with high speeds. Hence, any artifact is clearly noticeable in the solution movement. We simultaneously show results comparing local and global motion models regarding synthesis realism and performance. Finally, the quality of the synthesized animations is assessed by comparing our results against a per‐frame PIK technique. Copyright © 2007 John Wiley & Sons, Ltd.
Reaktionen eines N‐silylierten Iminophosphins (Phospha(III)azens) mit perfluorierten Ketonen
Authors: Röschenthaler Gerd‐Volker , Sauerbrey Karl , Schmutzler Reinhard
Published: June 2007

Das erste isolierbare Dreiringsystem 2, das Hexafluoraceton mit einem Hauptgruppenelement bildet, konnte durch 1,2‐Cycloaddition an das Iminophosphin 4 dargestellt werden. Perfluorbiacetyl ergibt das 4,5‐Bis(trifluormethyl)‐1,3,2λ5‐dioxaphosphol 8. Das analoge 4,4,5,5‐Tetrakis(trifluormethyl)‐1,3,2λ5‐dioxaphospholan 1a wurde durch Umsetzung von Lithium‐bis(trimethylsilyl)amid mit dem Phospholan 3 synthetisiert. Das Dimere von 4, Verbindung 5, addiert nur ein Molekül Perfluorbiacetyl unter Bildung des λ3λ5‐Diazadiphosphetidins 9.
Polyacetylenverbindungen, 246: Synthese von Acetylenverbindungen aus Alphonsea ventricosa
Authors: Bohlmann Ferdinand , Stöhr Frank , Staffeldt Jürgen
Published: June 2007

Die Konstitutionen der aus Alphonsea ventricosa isolierten Acetylenverbindungen 7, 8 und 17 werden durch Synthese sichergestellt. Für die Darstellung α‐substituierter Furane wird ein allgemein brauchbarer Weg beschrieben. Nach Hydroxylierung von Allylketonen erhält man säurekatalysiert in guter Ausbeute die entsprechenden Furane.
Über Metallalkyl‐ und ‐aryl‐Verbindungen, XX: Darstellung und Kristallstruktur des dimeren Phenyllithium · N, N, N′, N′‐Tetramethylethylendiamins, Bis[μ‐phenyl‐(N, N, N′, N′‐tetramethylethylendiamin)lithium]
Authors: Thoennes Detlef , Weiss Erwin
Published: June 2007

Das Addukt Phenyllithium · N, N, N′, N′‐Tetramethylethylendiamin wurde dargestellt und seine Kristallstruktur röntgenographisch ermittelt (R = 0.066, 1595 signifikante Reflexe). Die monokline Elementarzelle (Raumgruppe C2/c) enthält 4 Moleküle eines Dimeren. Ähnlich wie im dimeren Triphenylaluminium sind in jedem Molekül zwei Li‐Atome durch zwei Phenyl‐Gruppen verbrückt. Durch die Anlagerung eines Diamin‐Liganden erreicht jedes Li‐Atom vierfache Koordination.
Über die Reaktion von Platiniodiden mit Pyridin und über die Molekül‐ und Kristallstruktur von trans‐Diiodobis(pyridin)platin(II)
Authors: Thiele Gerhard , Wagner Dieter
Published: June 2007

Durch Umsetzung von Platiniodiden mit Pyridin wurden die Addukte PtI2 · n py (n = 2, 4, 6) und PtI4 · 2 py sowie das Hexaiodoplatinat (pyH)2PtI6 erhalten. Der thermische Abbau und die Schwingungsspekten der Addukte wurden studiert. Die Röntgenstrukturanalyse von PtI2 · 2 py ergab, daß in der monoklinen Elementarzelle vier isolierte, trans‐konfigurierte Moleküle enthalten sind.
13C‐NMR‐Spektroskopie von Norbornanderivaten, II: Einfluß homokonjugativer Wechselwirkungen auf die Carbonylverschiebung in Norbornanonsystemen
Authors: Bicker Richard , Kessler Horst , Steigel Alois , Zimmermann Gottfried
Published: June 2007

Es wird über die 13C‐NMR‐chemischen Verschiebungen von Norbornanonderivaten mit exo‐ oder endo‐Cyclopropanringen, endo‐Cyclobutanringen und/oder Doppelbindungen berichtet. Die gekreuzte Konjugation von Carbonylgruppe und Doppelbindung verursacht eine relativ starke Hochfeldverschiebung der Signale von C‐7 und eine geringere der olefinischen C‐Atome. Aus dieser Sicht verhalten sich die Carbonylverbindungen ähnlich wie die nichtklassischen 7‐Norbornyl‐Kationen. Die 13CO‐Verschiebung wird mit anderen molekularen Eigenschaften in Beziehung gesetzt: Solvolysegeschwindigkeit von 7‐Norbornylderivaten, Decarbonylierungsgeschwindigkeiten, n,π*‐Anregungsenergien und Photoelektronenspektren.
Theoretische und spektroskopische Untersuchungen an Indigofarbstoffen, XIX: Synthese und spektroskopische Eigenschaften eines sechsgliedrigen Thioindigo‐Grundchromophor‐Ringsystems
Authors: Luhmann Udo , Lüttke Wolfgang
Published: June 2007

Bei der oxidativen Dimerisierung des Thianons 4 entstehen, neben wenig trans‐6 mit dem Grundchromophorsystem des Thioindigos und der „Leukoverbindung”︁ 7, insbesondere der cis‐Indigo cis‐6 und die Trimeren 5a, b. Reaktionen mit besserer Ausbeute an trans‐6 und zur Darstellung seines Vinylogen 19 werden beschrieben. – Die spektroskopischen Eigenschaften dieser Verbindungen werden im Rahmen der Indigo‐Theorie diskutiert.
Synthese von Multifiden, dem Gameten‐Lockstoff der Braunalge Cutleria multifida, und von einigen seiner Isomeren Ein Beitrag zur Cope‐Umlagerung von 1‐Alkenylcyclopentenen
Authors: Boland Wilhelm , Jaenicke Lothar
Published: June 2007

Eine Synthese von Multifiden (1) sowie zwei seiner Strukturisomeren 16 und 17 wird beschrieben. Regioselektive Addition von Dihalogenketenen an dimeres Cyclopentadien 3 zu 4a/b bzw. 5a/b erlaubt einen einfachen Aufbau des Pheromonsystems.
Notizen. Radikalionen, XVIII: Existieren beständige Radikalkationen von Phosphinen?
Authors: Kaim Wolfgang , Bock Hans , Nöth Heinrich
Published: June 2007

Radical Ions, XVIII: Do Stable Radical Cations of Phosphines Exist?

The first persistent radical cation of a phosphine derivative, 2,3,5,6,7,8‐hexamethyl‐2,3,5,6,7,8‐hexaaza‐1,4‐diphosphabicyclo[2.2.2]octane (8), has been characterized by ESR spectroscopy.
Heterocyclische Siebenring‐Verbindungen, XXII. Synthese und thermische Umlagerung von substituierten 4‐Phenyl‐1‐benzothiepin‐1‐oxiden
Authors: Hofmann Hans , Gaube Helmut
Published: June 2007

Die 4‐Phenyl‐l‐benzothiepin‐l‐oxide 3a und b wurden sowohl über das Benzothiepinon‐1‐oxid 2 als auch durch direkte Oxidation der entsprechenden 4‐Phenyl‐ 1‐benzothiepine 6a und b dargestellt. Die Synthese von 3c und d erfolgte nur auf dem zweiten Weg. Weiteroxidation von 3a‐d führte zu den thermisch stabilen Dioxiden 4a–d. Die Thermolyse von 3a–d lieferte unter Abspaltung von SO die entsprechenden Naphthaline 5a–d. Die Geschwindigkeitskonstanten der Reaktion 3→5 wurden für je eine Temperatur bestimmt.
Ambivalentes Verhalten von Acyl(diphenyl)phosphanen gegenüber molekularem Sauerstoff
Authors: Lesiecki Hans , Lindner Ekkehard , Vordermaier Gottfried
Published: June 2007

Bei der „langsamen Oxidation”︁ der Acylphosphane RC(O)PPh2 (4a, b) [R  CH3 (a), CF3, (b)] mit molekularem Sauerstoff wird der dreibindige Phosphor unter Bildung der Phosphanoxide RC(O)P(O)Ph2 (l a, b) angegriffen, welche mit Wasser zu den Alkoholen RC[Ph2P(O)]2OX (2) und Phosphinaten RC[Ph2P(O)][OP(O)Ph2]X (3) weiterreagieren. Im Gegensatz hierzu erfolgt bei der „schnellen Oxidation”︁ der Angriff des Sauerstoffs an der Carbonylgruppe von 4a, b unter Bildung von CO2 und der Radikale · PPh2 und · R. Die Kombinationsprodukte dieser Radikale und die Abfangreaktion mit Wasser und Alkoholen werden beschrieben.
Anodische Hydroxylierung und Acetamidierung von konjugierten Dienen
Authors: Baltes Herbert , Stork Ludwig , Schäfer Hans J.
Published: June 2007

Die anodische Oxidation von 2,4‐Hexadien (1), 1,3‐Butadien (2) und 1,3‐Cyclohexadien (3) in Acetonitril/Wasser/Natriumperchlorat führt zu einem Gemisch aus Diolen, 2‐Oxazolinen und 3‐Pyrrolinen. Sorbinsäure‐methylester (5) liefert 4,5‐Epoxy‐(E)‐2‐hexensäure‐methylester (26); 1,4‐Diphenyl‐1,3‐butadien (4) wird zu Benzaldehyd (24) und Zimtaldehyd (25) gespalten. Die Produktverhältnisse werden vom Leitsalz beeinflußt. In Gegenwart von Tetrafluoroborat entstehen nahezu ausschließlich Diole, während die Elektrolyse in Acetamid/Acetonitril zu 2‐Oxazolinen und 3‐Pyrrolinen führt. Als Zwischenprodukte werden Radikalkationen (31) angenommen.
Basische Metalle, XI. Kationische (Cyclopentadienyl)rhodium‐Komplexe mit RhH‐, RhC‐, RhGe‐, RhSn‐ und RhHalogen‐Bindungen
Authors: Werner Helmut , Feser Rainer , Buchner Wolfgang
Published: June 2007

[C8H12RhCl]2 reagiert mit einem Überschuß von Trimethylphosphan zu [(PMe3)4Rh]Cl (1). In Lösungen von 1 findet ein sehr rascher Austausch der Phosphanliganden statt. Die Reaktion von 1 mit TIC5H5 führt zu dem Komplex C5H5Rh(PMe3)2 (9), der ein stark Lewis‐basisches Metallatom besitzt. 9 reagiert mit Elektrophilen Y+ sehr bereitwillig zu den Kationen [C5H5(PMe3)2RhY]+ die stabile RhH‐, RhAlkyl‐, RhAcyl‐, RhGe‐, RhSn‐ und RhHalogen‐Bindungen besitzen und als PF6‐Salze isoliert werden [Y = H (2), CH3 (3), C2H5 (4), COCH3 (10), COC6H5 (11), COC6H4OMe‐(p) (12), GeMe3 (7), SnMe3 (8), Br (15), Cl (13). 1(14)]. Bei der Reaktion von 9 mit CF3SO3SiMe3 in Ether entsteht neben [C5H5(PMe3),2RhH] + das Kation [Me3SiC5H4(PMe3)2RhH]+. Die Reduktion mit NaH in Tetrahydrofuran ergibt Me3SiC5H4Rh(PMe3)2.
Kristallstrukturen der Alkali‐isopropoxide des Kaliums, Rubidiums und Caesiums
Authors: Greiser Thomas , Weiss Erwin
Published: June 2007

Die Isopropoxide des Kaliums, Rubidiums und Caesiums sind isostrukturell tetragonale Raum‐gruppe P4/nmm‐D). Ihre Zellkonstanten wurden ermittelt und die Struktur des Caesium‐isopropoxids anhand eines Einkristalls röntgenographisch bestimmt und bis R = 0.069 verfeinert. Die Alkoxide bilden Schichtgitter vom Typ des Lithium‐ bzw. Natriummethoxids. Dabei liegen die Metallatome in einer Ebene und sind beiderseits von O‐Atomen koordiniert, indem jedes O‐Atom von vier Metallatomen und einem sec. C‐Atom umgeben ist. Die Methyl‐C‐Atome sind statistisch auf zwei Lagen verteilt, welche sich durch Drehung der (CH3)2CH‐Gruppe um 90° unterscheiden.
Ligandstruktur und Komplexierung, XLIV. Synthese und Selektivität neuartiger vierarmiger nichtcyclischer Neutralliganden
Authors: Vögtle Fritz , Müller Walter M. , Buhleier Egon , Wehner Winfried
Published: June 2007

Neue nichtcyclische Neutralligandsysteme 4–6 und 8–11 vom Tetrapodentyp 3 mit verschiedenen Endgruppen wurden synthetisiert. Die Kation‐Selektivität hängt von der Endgruppenstruktur ab. Die potentiometrisch bestimmten Komplexstabilitätskonstanten liegen i. a. zwischen denjenigen der Tripoden‐ (2) und Dipoden‐Liganden (1). Zahlreiche kristalline Komplexe der vierarmigen Komplexbildner sowie einiger zum Vergleich synthetisierter neuer Dipodanden (14–16) mit Alkali‐ und Erdalkalimetallsalzen wurden erhalten.
Stoffwechselprodukte von Mikroorganismen, 172. Isolierung des Antibioticums semi‐Vioxanthin aus Penicillium citreo‐viride und Synthese des Xanthomegnins
Authors: Zeeck Axel , Ruß Peter , Laatsch Hartmut , Loeffler Wolfgang , Wehrle Herbert , Zähner Hans , Holst Hartwig
Published: June 2007

Neben Xanthomegnin (16b), 3,4‐Dehydroxanthomegnin (29 a), Viomellein (23) und Vioxanthin (3) wurde aus Penicillium citreo‐viride unter veränderten Kulturbedingungen semi‐Vioxanthin (7) isoliert. Konstitution 7 folgt aus den Spektren und dem Befund, daß mit Fremy‐Salz 3,4,6,9‐Tetrahydro‐10‐hydroxy‐7‐methoxy‐3‐methyl‐1,6,9‐trioxo‐1H‐naphtho[2.3‐c]pyran (9a = semi‐Xanthomegnin) entsteht. – Das durch Entmethylierung von 9a zugängliche 9c ließ sich mit Kaliumpersulfat/Natriumhydroxid zu 16a dimerisieren, das zu 16b methyliert wurde. Synthetisches 16b war mit nativem Xanthomegnin identisch, was die von Höfle und Röser9) revidierte Konstitution bestätigt und beweist, daß die Farbstoffe der Xanthomegnin‐Reihe biogenetisch einheitlich sind. – Die Stoffwechselprodukte des Stammes hemmen das Wachstum von Bakterien, 16b und 23 wirken ferner gegen Insekten.
Mikrobiologische Umwandlung von Steroiden, XVI. Synthese von 11β, 21‐Dihydroxy‐6, 16α‐dimethyl‐1,4,6,‐pregnatrien‐3,20‐dion und dessen 11‐Ketoverbindung
Authors: Kieslich Klaus , Wieglepp Heinz , Hoyer Georg‐Alexander
Published: June 2007

21‐Acetoxy‐5α,6α‐epoxy‐3β‐hydroxy‐6β,16α‐dimethyl‐20‐pregnanon (3a), dargestellt aus 3β‐Hydroxy‐6, 16α‐dimethyl‐5‐pregnen‐20‐on (1) durch Epoxidierung und 21‐Acetoxylierung, wurde mit Flavobacterium dehydrogenans zu 6α,21‐Dihydroxy‐6β, 16α, ‐dimethyl‐4‐pregnen‐3,20‐dion (4) oxidiert und zu 21‐Hydroxy‐6, 16α‐dimethyl‐4,6‐pregnadien‐3,20‐dion (5) dehydratisiert. Mit Curvularia lunata wurde die 11β‐Hydroxygruppe eingeführt zu 6, während Aspergillus ochraceus die entsprechende 11α‐Hydroxyverbindung 8 ergab. Beide Verbindungen wurden mit Bacillus lentus zu 7 bzw. 9 dehydriert. Die 11α‐Hydroxyverbindung 9 wurde nach selektiver Acetylierung der 21‐Hydroxygruppe zu 10 zum 11‐Keton 11 oxidiert, dessen Verseifung 12 ergab.
Cycloadditionsreaktionen von Heterocumulenen, XVII. Über den Mechanismus der [2+2]‐Cycloaddition von Thioketenen mit Azomethinen
Authors: Schaumann Ernst , Ehlers Jörn
Published: June 2007

Das Thioketen 1 reagiert mit den Azomethinen 2a – zu den β‐Thiolactamen 3a–f, deren Struktur durch Methylierung zu 7 und Oxidation zu 8/9c belegt wurde. Versuche, die potentielle Zwischenstufe der Cycloaddition 11 abzufangen, verliefen negativ. Nach kinetischen Untersuchungen sind Lösungsmittel‐und Substituenteneinflüsse auf die Cycloadditionsgeschwindigkeit gering. Ausgehend von 1‐deuteriertem und 1‐undeuteriertem 2b wurde ein sekundärer Isotopeneffekt gemessen. Diese Ergebnisse wie auch die Bildung des sterisch ungünstigen Cycloaddukts 3A sprechen dafür, daß im geschwindigkeitsbestimmenden Schritt der Cycloaddition kein „klassischer”︁ Dipol 11 entsteht, sondern unter Orbitalsymmetrie‐Kontrolle die dipolare Species 14.
Neue Synthesen mit Diazodiketonen, IV. Cyclische S‐Oxide
Authors: Capuano Lilly , Urhahn Gerd , Willmes Arnold
Published: June 2007

Die 3,4‐Dihydro‐1,2,3‐oxathiazin‐ 4 und 1,2‐Oxazetidin‐S‐oxide 5 werden a) durch Thermolyse der Diazodiketone 1 mit N‐Sulfinylaminen 3 b) durch basenkatalysierte Kondensation der aus 1 leicht zugänglichen 2‐Acylacetamide 6 mit Thionylchlorid hergestellt. Aus 6 weden die Aminoacrylamide 7 erhalten. Diese reagieren mit Thionylchlorid je nach der verwendeten Base entweder zu monocyclischen 3,6‐Dihydro‐1,2,6‐thiadiazin‐S‐oxiden 10 oder über eine Imidoylketenimin Zwischenstufe 9 zu den 4‐Aminochinolinen 8. – Der SO‐Einbau mittels Thionylchlorid in (hetero)‐cyclische Iminocarboxamide, Diamine und Aminophenole führt zu den S‐oxiden 13 kondensierter Thiadiazine, 15a–c des Benzothiadiazols bzw. 15d des Benzoxathiazols.
Synthese, Strukturaufklärung und Konformationsuntersuchungen 1→4‐verknüpfter Disaccharidglycoside vom 2,3‐Anhydro‐4‐O‐(hex‐2‐enopyranosyl)‐α‐D‐allopyranosid‐Typ
Authors: Thiem Joachim , Schwentner Jens , Schüttpelz Eike , Kopf Jürgen
Published: June 2007

Durch sauer katalysierte Addition der 2,3‐Anhydro‐α‐D‐allopyranoside 2 bzw. 7 an Triacetyl‐D‐glucal (1) bzw. Tetraacetyl‐2‐hydroxy‐D‐glucal (6) lassen sich unter Allylumlagerung die α1→4‐verknüpften Disaccharide 4, 5 und 9 mit Hex‐2‐enopyranosyl‐Struktur im nicht‐reduzierenden Saccharidring milde und in guten Ausbeuten kristallin gewinnen. Durch Hydrierung von 4 und 5 wird 8 erhalten, bei dem die interglycosidische α‐Verknüpfung nachgewiesen wird. Die Röntgenstrukturanalyse von 5 bestätigt die α‐Verknüpfung in dem erheblich gestreckten Disaccharidderivat. Beide Saccharidringe weisen eine SO5‐Sofakonformation auf, bei der nur die Atome C‐5 und C‐5′ wesentlich aus der Ebene der übrigen Ringatome nach unten herausstehen. Konformationsbetrachtungen legen auch in Lösung für 5 und 9 das Vorliegen einer SO5‐Sofakonformation nahe. Das interglycosidische β‐Isomere 10 weist dagegen eine 5SO‐Sofakonformation auf, was auf den Allyleffekt zurückgeführt werden kann.
Tertiäres Phosphan/Hexachlorethan als Kondensationsreagenz für die Peptidsynthese
Authors: Apple Rolf , Willms Lothar
Published: June 2007

Mit dem Dehydratisierungsreagenz tertiäres Phosphan/Hexachlorethan lassen sich N‐geschützte Aminosäuren und Aminosäureester in hohen Ausbeuten zu Peptiden kondensieren. Funktionelle Gruppen in den Seitenketten von Serin, Threonin, Tyrosin, Asparagin und Glutamin werden nicht angegriffen Unter Zusatz von 1‐Hydroxybenzotriazol verläuft der Anderson‐Test racemisierungsfrei.
Notiz über die Synthese des 6‐Hydroxy‐2‐isopropyl‐5‐methoxy‐3(2H)‐benzofuranons
Authors: Bohlmann Ferdinand , Vorwerk Edgar
Published: June 2007

Note on the Synthesis of 6‐Hydroxy‐2‐isopropyl‐5‐methoxy‐3(2H)‐benzofurnanone

The benzofuraone 4 isolated from an Othonna species has been synthesized to establish the substitution pattern.
2,3‐Diphenyl‐2,3‐diazabicyclo[2.2.2]octan
Authors: Neugebauer Franz A. , Weger Helmuth
Published: June 2007

2,3‐Diphenyl‐2,3‐diazabicyclo[2.2.2]octane

The title compound 5 was synthesized by twofold arylation of 2,3‐diazabicyclo[2.2.2]oct‐2‐ene (1). The conformational features of 5 are discussed using 1H NMR and PE data.
Eine einfache Synthese von Norcaradien‐7,7‐dicarbonitril
Authors: Klärner Frank‐Gerrit , Adamsky Friedhelm , Wette Michael
Published: June 2007

A Simple Synthesis of Norcaradiene‐7,7‐dicarbonitrile

Alternatively to the synthesis reported by Ciganek 1) title‐compound 4 can be prepared by reaction of anion 2 with 2‐naphthyl cyanate.
Über C,P‐diphosphinosubstituierte Methylenphosphorane
Authors: Appel Rolf , Wander Manfred , Knoll Fritz
Published: June 2007

Bei der Umsetzung von Lithium‐bis(diorganylphosphino)methanid (2a, c) mit Dialkylchlorphosphanen reagiert nicht das C‐, sondern ein P‐Atom von 2 als nucleophiles Zentrum. Unter PP‐Verknüpfung entstehen die [(Diphenylphosphino)methylen](diorganylphosphino)diorganylphosphorane 5a–c.
Synthetische Arbeiten in der Reihe der aromatischen Erythrina Alkaloide, XXIV. Über die Bromierungsprodukte von 15,16‐Dimethoxy‐cis‐erythrinan‐2,8‐dion
Authors: Mondon Albert , Epe Monika , Wolff Christian , Clausen Thomas , Vilhuber Heinz Georg
Published: June 2007

Das Bromketolactam 2 wird aus 1 durch Bromierung oder aus 5 durch Hydrolyse unter Umkehrung der Konfiguration an C‐l erhalten. Auch die entgegengesetzte Reaktion von 2 nach 5 verläuft unter Umkehr. Mit Natriumboranat liefert 2 die Bromhydrine 11, 12, 13 und das Epoxid 17. Bei der Bildung von 12 und 13 ist wieder das selbst nicht faßbare epimere Bromketolactam 6 Zwischenprodukt. Die Umsetzung von 2 mit Kaliumhydroxid in Methanol oder Ethylenglycol führt zu den Hydroxyacetalen 18 oder 19. Die aus 1 dargestellten Dibromketone 24 und 25 haben auffallende spektroskopische Eigenschaften.
Mesomere Kationen, V. π‐Donoreigenschaften von Sauerstoff und Schwefel — DNMR‐Studien an aromatischen Uronium‐ und Thiouroniumsalzen zur Frage der planaren Inversion am Sauerstoff und Schwefel
Authors: Kalinowski Hans‐Otto , Kessler Horst
Published: June 2007

Die Energiebarrieren der Z,E‐Topomerisierung an der partiellen CO‐ bzw. CS‐Doppelbindung werden durch 1H‐DNMR‐spektroskopische Untersuchungen an aromatischen Uronium‐und Thiouroniumsalzen 1–4 nach dem Koaleszenzverfahren und z. T. durch vollständige Linienformanalyse bestimmt. Die Substituentenabhängigkeit der Isomerisierungsbarriere zeigt, daß die Z,E‐Topomerisierung in beiden Verbindungsklassen nach dem Rotationsmechanismus erfolgt. Dies steht im Gegensatz zu den Befunden an den isoelektronischen Guanidinen, die einen Inversionsmechanismus bevorzugen, was jedoch mit Hilfe der MO‐Theorie verstanden werden kann. Der Vergleich der beobachteten Rotationsbarrieren mit denen in Guanidiniumsalzen führt zur folgenden Abstufung der Stabilisierung des benachbarten Carbeniumkohlenstoffes durch die Heteroatome: N > S > O. Diese Reihung steht in Übereinstimmung mit ab initio‐Berechnungen zur π‐Donorfähigkeit von Heteroelementen in den Verbindungen ⊕CH2X (X = OH, SH, NH2).