bluuebunny/crossref_metadata_2025_split huggingface dataset:
Notiz über eine regiospezifische Methode zur Herstellung von konjugierten Cyclohexadienen Über synthetische Methoden, 11. Mitteilung
Authors: Rüttimann August , Wick Alexander , Eschenmoser Albert 
Published: December 2004

Abstractβ,γ‐unsaturated δ‐hydroxy‐cyclohexene carboxylic acids undergo a smooth decarboxylative elimination when treated with DMF‐dineopentylacetal in an unpolar solvent. The reaction provides a method for the regiospecific preparation of 1,3‐cyclohexadiene derivatives under non‐isomerizing conditions, starting from easily accessible and structurally variable intermediates.
Utilisation d'ylides du phosphore en chimie des sucres XXIII Eliminations accompagnant certaines réactions de Wittig
Authors: Tronchet Jean M. J. , Cottet Christian , Barbalat‐Rey Françoise 
Published: December 2004

AbstractSome reactions of 3‐O‐alkyl‐6‐deoxy‐1,2‐O‐isopropylidene‐α‐D‐xylo‐hexofuranos‐5‐uloses (1 and 2) with Wittig reagents are described. These ketosugars react with methylenetriphenylphosphorane and benzylidenetriphenylphosphorane to give the expected unsaturated branched‐chain sugars and dienes formed by elimination of H–C(4) and the 3‐alkyloxy group. Structural studies on all these compounds have been effected using NMR. spectroscopy and particularly, when necessary, nuclear Overhauser Effect. One important by‐product of these reactions is an unsaturated ketone 3,6‐dideoxy‐1,2‐O‐isopropylidene‐α‐D‐glycero‐hex‐3‐enofuranos‐5‐ulose (6). Compounds 1 and 2 do not react with cyanomethylenetriphenylphosphorane.
Biosynthesis of Cytochalasans. Part 4. The mode of incorporation of common naturally‐occurring carboxylic acids into cytochalasin D
Authors: Vederas John C. , Graf Werner , David Lucien , Tamm Christoph 
Published: December 2004

AbstractUtilization of sodium [1‐14C]‐, [2–14C]‐, and [1,2‐13C]‐acetates, [1‐14C]‐, [1‐13C]‐, or [2‐14C]‐propionates, [1‐14C]‐or [2‐14C]‐malonates, of [1‐14C]‐ or of [1‐14C]‐myristic acid, or of [1‐14C]‐ and [1‐14C]‐palmitic acid in the biosynthesis of cytochalasin D (1) by Zygosporium masonii was determined by degradation studies or by carbon magnetic resonance spectroscopy. The precursors were incorporated primarily via the acetate‐malonate pathway to generate 1 from nine intact acetate units, eight of which are coupled in a head to tail fashion to form the C16‐polyketide moiety.
1‐Aralkylated Tetrahydro‐2‐benzazepines. Part I: Synthesis from methoxylated phenylpropionamides
Authors: Berney Daniel , Schuh Karlheinz 
Published: December 2004

AbstractPhenylpropionamides acylated in the ortho position with aralkanecarboxylic acids were cyclised to give, after reduction, 1‐aralkyl‐tetrahydro‐2‐benzazepines.
Über die Hydrierung von Aminalen
Authors: Zondler Helmut , Pfleiderer Wolfgang 
Published: December 2004

The catalytic hydrogenation of aminalsThe catalytic hydrogenation of aminals, the bis‐N‐analogs of acetals, was investigated. 3‐(γ‐Aminopropyl)‐piperidines are formed by the hydrogenolytic splitting of the C–N‐bond of decahydro‐1, 8‐naphthyridines. The reaction is stereospecifically influenced by the catalyst used. Non cyclic aminals are hydrogenated in the same manner. The mass and NMR. Spectra of 3‐(γ‐aminopropyl)‐piperidines are discussed.
Templat‐Reaktionen II. Herstellung von tricyclischen und tetracyclischen Metallkomplexen aus aliphatischen Diaminen und Phenylazo‐malondialdehyd‐Derivaten
Authors: L'Eplattenier François A. , Pugin André 
Published: December 2004

Template‐Reactions II. Syntheses of tricyclic and tetracyclic metal complexes from aliphatic diamines and phenylazo‐malondialdehyde‐derivativesA template synthesis of metal complexes with 14‐ and 16‐membered macrocycles 6 resp. 10 has been devised. These compounds are obtained in high yield by the condensation of aliphatic 1,2‐or 1,3‐diamines with phenylazo‐malon‐dialdehydes in the presence of divalent metal ions such as Cu(II) and Ni(II). This is the first reported one‐step synthesis of tetraaza‐annulenes with aliphatic diamines. The formation of the intermediate tricyclic complexes 5 and 9, obtained either by a template or a nontemplate synthesis, is also described. Ring closure with diamines leads again to 6 and 10 or to asymmetric tetraaza‐macrocyclic systems such as 7 or 11.
The gas–solid interface The Interaction of Argon, Xenon and Sulfur Hexafluoride with Rhombic Sulfur
Authors: Stoeckli Fritz , Stoeckli‐Evans Helen 
Published: December 2004

AbstractFurther theoretical calculations have been carried out for the adsorption potentials of Ar on the (011) face of rhombic sulfur, and for Xe and SF6 on the (011) and (111) faces. By using the same sites for the three molecules and pair‐potentials of the Lennard‐Jones type, specific scaling factors were found. These are constant within 5–10%, for each adsorbate, and therefore the distribution curves of the adsorption potentials of simple molecules on crystalline sulfur are related in a simple way. The influence of the size of the molecule and the local geometry of the surface is also discussed.
The gas‐solid interface physical adsorption of Simple Molecules in Slot‐Like Micropores
Authors: Perret André , Stoeckli Fritz 
Published: December 2004

AbstractAdsorption potentials of simple molecules on various active carbons have been calculated directly from GSC. measurements, by using the procedure of Hansen et al. The model of slot‐like micropores developed earlier, and based on a 3–9 adsorption potential, leads to consistent results. It reveals the existence of micropores having widths between 6.5 and 7.5 Å, in agreement with other methods.
Die Kristallstruktur eines dinuklearen Peroxotitan(IV)‐nitrilotriacetatkomplexes
Authors: Schwarzenbach Dieter , Girgis Kamal 
Published: December 2004

Crystal Structure of a Dinuclear Peroxotitanium(IV)‐Nitrilotriacetate ComplexThe structures of four peroxotitanium(IV) dipicolinates, with colours ranging from deep red to yellow orange, have been reported earlier, and a correlation between their colours and the variations of certain bond lengths has been proposed. This paper describes the pale yellow dinuclear peroxotitanium nitrilotriacetate complex Na4[Ti2O5(C6H6O6N)2]11 H2O. The monoclinic structure, space group B2/b, contains 25 independent non‐hydrogen atoms and 17 hydrogen atoms. It has been determined from diffractometer data and refined to R = 3.2%. Titanium is again coordinated approximately pentagonal‐bipyramidally. The μ‐oxygen bridge occupies an axial position. The short (1.819 Å), nearly linear Ti–O–Ti bonds show double bond character. The titaniumperoxide bonds, however, are relatively long, thus confirming the rule proposed before: the more basic the axial ligands, the higher is the frequency of the absorption band, the longer are the Ti‐peroxide bonds and the shorter are the axial distances. This is confirmed by electron density maps, which are to be discussed elsewhere in detail, showing bent Ti‐peroxide bonds enclosing an angle of about 70° and a strong electron bridge on the μ‐oxygen bond. Hydrogen bonding and the packing of the complexes is discussed.
Neue β‐Lactam‐Antibiotika. Über die Funktionalisierung der Cephem‐3‐Stellung mittels Schwefel oder Stickstoff. Modifikationen von Antibiotika, 13. Mitteilung
Authors: Scartazzini Riccardo , Schneider Peter , Bickel Hans 
Published: December 2004

New β‐lactam antibiotics. Functionalisation of the cephem 3‐position with sulfur or nitrogen bearing substituentsThe tosylate sulfoxides or mesylates derived from the 3‐hydroxy‐ceph‐3‐em esters 1a, b reacted with thiols to give 3‐thioethers which were converted into the microbiologically active acids 7a, c, 8a, c 9c, and 13c by known procedures. The 3‐methylsulfonyl‐derivative 17c was prepared from 6b. The synthesis of the 3‐acylamino‐ceph‐3‐em‐4‐carboxylic acids 23c and 24c is reported.
Sind Zwischenstufen mit pentakoordinierten C‐Atomen bei aliphatischen SN2‐Reaktionen nachgewiesen??
Authors: Vergnani Tiziana , Karpf Martin , Hoesch Lienhard , Dreiding André S. 
Published: December 2004

How valid is the proof of existence of intermediates with pentacoordinated C‐atoms in aliphatic SN2‐reactions?Retention of configuration in the preparative conversion of cis‐3‐ethoxycyclobutylbrosylate (4) with sodium iodide and with lithium bromide in boiling acetone for 5 days to cis‐3‐ethoxycyclobutyliodide (6) and bromide (8), respectively, has been published by Ugi et al. to be the basis of a proof that species with pentacoordinated C‐atoms exist sufficiently long during aliphatic SN2‐reactions that they can undergo ligand reorganizations.It is now shown that the conditions used lead to a thermodynamic control, inasmuch as the cis‐ and trans‐halides 6 and 7, as well as 8 and 9 isomerize to ∼2:1 equilibrium mixtures. Furthermore it is shown that the reaction of kinetic control occurs with inversion, inasmuch as the trans‐: cis‐halide ratio during the course of the reaction starts with high values and falls slowly to the equilibrium.Thus the nucleophilic substitutions on the examined four‐membered ring system do not contravene previous experience with other aliphatic and alicyclic systems, so that the existence of pentacoordinated carbon species as intermediates in aliphatic SN2‐reactions cannot be considered as proven.
Pseurotin, a New Metabolite of Pseudeurotium ovalis STOLK Having an Unusual Hetero‐Spirocyclic System. (Preliminary Communication)
Authors: Bloch Peter , Tamm Christoph , Bollinger Pietro , Petcher Trevor J. , Weber Hans Peter 
Published: December 2004

AbstractThe structure and absolute configuration of pseurotin (1), a new metabolite, isolated from culture filtrates of Pseudeurotium ovalis STOLK (Ascomycetes), has been shown to be 2‐[1′(S), 2′ (S)‐dihydroxhex‐3′‐ene‐yl]‐3‐methyl‐8(S)‐methoxy‐8‐benzoyl‐9(R)‐hydroxy‐(5S)‐1‐oxa‐7‐aza‐spiro[4.4]non‐2‐ene‐4, 6‐dione (1), by spectral data and chemical transformations, and by X‐ray analysis of its dibromo derivative 2 [1].
Photochemische Reaktionen. 86. Mitteilung [1]. Zur Photolyse von Bicyclo[3.3.1]nonan‐2‐on
Authors: Duthaler Rudolf Otto , Stingelin‐Schmid Regula Susanna , Ganter Camille 
Published: December 2004

Photolysis of Bicyclo[3.3.1]nonan‐2‐one.Disproportionations to the unsaturated aldehydes 2 and 3 or the ketene 4, the secondary processes available to the acyl‐alkyl biradical b[X(9) = CH2] formed from bicyclo[3.3.1]nonan‐2‐one (1) in a primary photochemical process by α‐cleavage (Norrish type I cleavage), were studied.If the acyl‐alkyl biradical b [X(9) = CH2] has a lifetime sufficient to permit rotation around one or several bonds before H‐transfer occurs, considerations about the energetically most favored conformations of b allow to deduce the following preference for intramolecular H‐abstraction: at C(9) (f → unsaturated aldehyde 2) > at C(3) (1 → ketene 4) > at C(8) (i → unsaturated aldehyde 3). If H‐transfer takes place very quickly, following an energetically favored small conformational change of the acyl‐alkyl biradical, one expects H‐abstraction at C(9) and/or C(3) to be preferred over that at C(8). These predictions were fully confirmed by the experiments.UV. irradiation of bicyclo[3.3.1]nonan‐2‐one (1) in n‐pentane gave a complex mixture of the unsaturated aldehyde 2 and products of further photochemical reactions of 2:43 and 44, 45 and 46, 49–52, and 54–57 (see below). Photolysis of 1 in methanol, however, yielded 82% of 2 and 1,2% of ester 23, the final product from ketene 4 formed by trapping of a solvent molecule.UV. irradiation of the 9,9‐dideuterio‐ketone 20 confirmed the intramolecular D‐abstraction at C(9) (→ unsaturated aldehyde 21) and consequently the H‐abstraction at C(9) in the sequence 1 → 2. That either of the two H‐atoms at C(9) in 1 can be abstracted was demonstrated by the photolysis of the C(9)‐epimeric 9‐acetoxy‐bicyclo[3.3.1]nonan‐2‐ones 24 and 25 in methanol. In both cases the unsaturated aldehyde 26 was formed, which corresponds to abstraction of H—C(9)c(7) and H—C(9)C(3)15, respectively.In separate UV. irradiation experiments it was shown that the products accompanying the unsaturated aldehyde 2 (photolysis of 1 in n‐pentane) were formed in the following ways: diene 43 and acetaldehyde (44) from 2 by intramolecular γ‐H abstraction followed by Norrish type II reaction; the spiro‐alcohols 45 and 46 from 2 by intramolecular γ‐H abstraction followed by ring closure to cyclobutanols; the oxetanes 49–52 by cycloaddition (Paterno‐Büchi reaction) of acetaldehyde (44) to 3‐methylidene‐cyclohexene (43); the aliphatic alcohols 54–57 by addition of acetaldehyde (44) to n‐pentane, i.e. H‐abstraction from the hydrocarbon solvent followed by combination of the radicals thereby formed.
Eine Synthese von Vitamin A nach der Sulfonmethode
Authors: Fischli Albert , Mayer Hans , Simon Werner , Stoller Hans‐Jörg 
Published: December 2004

A Synthesis of Vitamin A According to the Sulfone Method.Starting from β‐ionyl phenyl sulfone 7 and an appropriate allylic chloride 10 retinol 14 has been prepared by a direct procedure. Subsequent acetylation and isomerization led to crystalline all‐E‐vitamin A acetate 16.
Photochemische Reaktionen. 87. Mitteilung. Zur Photolyse von 9‐Oxabicyclo[3.3.1]nonan‐2‐on
Authors: Duthaler Rudolf Otto , Ganter Camille 
Published: December 2004

Photolysis of Bicyclo[3.3.1]nonan‐2‐one.Disproportionations, the secondary processes available to the acyl‐alkyl biradical b (X(9) = 0) formed from 9‐oxabicyclo[3.3.1]‐nonan‐2‐ones a (X(9) = 0) in a primary photochemical process by α‐cleavage (Norrish type I cleavage) were studied. Special attention was paid to the selectivity between the two possible H‐abstractions: the one at C(3) (→ ketene c, X(9)= 0) and the other one at C(8) (→ alkenal d, X(9) = 0) and to the selectivity of the H‐abstraction at a definite methylene group (C(3) or C(8)). In the case of ketene formation (→ c, X(9) = 0) the specificity of the insertion of the migrating H‐atom at C(1) was studied. endo‐6‐Hydroxy‐9‐oxabicyclo[3.3.1]nonan‐2‐one (6) and derivatives of it (7, 8, 16, 17, 19, 21, 30 and 38) as well as exo‐6‐hydroxy‐9‐oxabicyclo[3.3.1]‐nonan‐2‐one (41) and its derivative 42 were used as substrates.UV.‐irradiation of 6 in benzene yielded 1,5‐dioxa‐2‐cis‐decalone (44) by way of a ketene g (R = H) as demonstrated by the photolysis of 7 (→ 45), 8 (→ 43), and 17 (→ 47). Specific labellings with deuterium proved that H‐abstraction occurs intramolecularly at C(3) (e.g. 16 → 54; 6 + 16 → 44 + 54), that one of the H‐atoms at C(3) migrates specifically to C(1) (21 → 55; 19 → 56), endo‐H–C(3) being favored by a factor of 6. The abstraction showed an unexpected primary isotope effect of about 2.UV‐irradiation of 41 in benzene yielded in addition to the expected 1,5‐dioxa‐2‐trans‐clecalone (63) about 3% of an isomeric compound 67 which probably results from H‐abstraction at C(8) (→ alkenal 65) followed by cyclisation.
Die Synthese von 2,2′‐Dinor‐carotinoiden
Authors: Kienzle Frank , Minder Rudolf E. 
Published: December 2004

The Synthesis of 2,2′‐Dinor‐carotenoids.2,2′‐Dinor‐carotenoids which include the naturally occurring actinioerythrol (1) and the blue carotenoid violerythrin (2) have been obtained by total synthesis. The synthesis starts with acetone and acetylene and yields compounds 1 and 2 as well as other carotenoids of the same type.
Biosynthesis of Cytochalasans. Part 6. The Mode of Incorporation of Phenylalanine into Cytochalasin D
Authors: Vederas John C. , Tamm Christoph 
Published: December 2004

AbstractRapid equilibrium of D‐ and L‐phenylalanines with phenylpyruvic acid (4) was shown to account for their equally efficient incorporation into cytochalasin D (1) by Zygosporium masonii. Transamination of phenylalanines stereospecifically labelled with tritium at C(2) and C(3) proceeded with complete hydrogen loss at the α position and extensive loss at the β position. Considerable suppression of the incorporation of the D‐amino acid by phenylpyruvic acid (4) indicated that the L‐enantiomer is the primary precursor of 1.
Comments on Empirical Correlations between Reduction Potential of Carbon‐Halogen Bonds and NQR. Frequencies of Halogen Atoms in Organic Molecules
Authors: Gerdil Raymond 
Published: December 2004

AbstractAn empirical linear correlation exists between nuclear quadrupole resonance frequencies of halogen nuclei (35Cl, 79Br, 127I) and the polarographic reduction potentials in series of organic halides. In terms of electronic structure this is interpreted as a significant relationship between the average p‐electron population at halogen atoms and the first vacant molecular orbital of halogenated molecules. On the basis of the present correlations conclusions are drawn about some controversial mechanistic aspects of the electroreduction of the carbon‐halogen bond.
Réactions d'addition‐élimination à partir d'hétérocycles germaniés du type R2Ge. II. Les germa‐2‐diazolidines‐1,3
Authors: Lavayssière Hélène , Dousse Gabriel , Satgé Jacques 
Published: December 2004

Addition‐elimination reactions from germanium heterocycles . II. 2‐Germa‐1,3‐diazolidines (X  Y  NMe).The reactivity of 2‐Germa‐1,3‐diazolidines with unsaturated compounds such as heterocumulenes (CS2, PhNCO, PhNCS) and with carbonyl compounds (aldehydes and ketones) has been investigated. Generally the formation of mono‐ and diinsertion derivatives is observed. The elimination reactions of (Et2GeO)n and (Et2GeS)3 from these addition derivatives lead to corresponding carbon diazolidines.The mechanism of these addition‐elimination reactions is precised. The interest of these reactions in organic synthesis is underlined.
The Photoelectron Spectrum of Tetracyanomethane
Authors: Bock Hans , Stafast Herbert , Haselbach Edwin , Maier Erwin 
Published: December 2004

AbstractThe helium (I) photoelectron spectrum of C(CN)4 curiously displays ionizations only in two small windows from 13.8 eV to 14.5 eV and from 14.8 eV to 15.5 eV, respectively. A tentative assignment of the numerous overlapping bands – based on a spectroscopically parametrized LCBO MO model – correlates satisfactorily with ionization potentials of other cyano compounds as well as of tetrahalomethanes.
Zur Kenntnis der stickstoffhaltigen Inhaltsstoffe von Castoreum
Authors: Maurer B. , Ohloff G. 
Published: December 2004

Investigation of the Nitrogen‐containing Compounds of Castoreum.Fourteen nitrogen‐containing compounds, 2–15, have been identified for the first time from the scent gland of the Canadian beaver. Seven of them, 2–8, are closely related to the alkaloid (−)‐castoramine (1), the only base isolated so far from this source.
Vergleich der Produkte aus der Reaktion von Phenylguanidin‐Derivaten mit β‐Ketoestern bzw. Propiolsäureestern (Synthese von Pyrimidonen)
Authors: Härter Hans Peter , Lichti Heinz , Stauss Urs , Schindler Othmar 
Published: December 2004

Comparison of reaction products afforded by phenylguanidine derivatives with β‐ketoesters or propiolic esters, respectively (synthesis of pyrimidones).2‐Anilino‐imidazolines, when treated with either β‐ketoesters or propiolic esters, yield two isomeric groups of pyrimidones. The isomerism is based on different positions of the carbonyl group in the pyrimidone ring. The mass spectra permit an unequivocal assignment of constitution I to the product formed with β‐ketoesters and of constitution V to that formed with propiolic esters. Additionally, 2‐(2‐amino‐anilino)‐2‐imidazoline (XII) when treated with methyl phenylpropiolate yields IX; while treatment with ethyl benzoylacetate yields XIII as an intermediate, which eliminates spontaneously one molecule of water to give the benzimidazole derivative XIV. Phenylguanidines (XV) add propiolic esters in the same way as do imidazoline derivatives. Photochemical cleavage of two carbon atoms with their adherent hydrogen atoms from the imidazole ring of the pyrimidones (V) leads to aminopyrimidine derivatives, e.g. XVI.
Die kristalline und molekulare Struktur von cis‐Coleon D, einem cis‐A/B‐6,7‐Diketo‐abietan‐Derivat
Authors: Weber Hans Peter , Petcher Trevor J. , Rüedi Peter , Eugster Conrad Hans 
Published: December 2004

The Crystal and Molecular Structure of cis‐Coleon D, a cis‐A/B‐6,7‐Dioxo Derivative of Abietane.The X‐ray analysis of cis‐Coleon D (1) confirmed the postulated position of HC(5) in the plane of the neighbouring keto group. This situation is unfavourable for enolisation, in contrast to the situation where the HC(5) is perpendicular to the keto plane, as supposed in trans‐Coleon D (2). The α‐diketone moiety has a significant (P)‐helicity of about 10 (1)°. The acentric crystal structure of cis‐Coleon D was determined by direct methods and refined with 1533 structure amplitudes to R = 0.042. The absolute configuration was determined from the known chirality of the A/B‐ring junction.
The Rearrangement of α‐Acetylenic Alcohols to α, β‐Unsaturated Carbonyl Compounds by Silylvanadate Catalysts
Authors: Pauling Horst , Andrews David Arthur , Hindley Nathan Chadwick 
Published: December 2004

AbstractNew catalytic systems have been found which effect the isomerization of α‐acetylenic alcohols to the corresponding α, β‐unsaturated carbonyl compounds with high efficiency. These are combinations of silylvanadates with silanols or silanediols.
A Photo‐initiated Wagner‐Meerwein Rearrangement. Preliminary communication
Authors: Thomas Alan F. , Ozainne Michel 
Published: December 2004

AbstractIrradiation of the octalin‐derived sesquiterpene oxide α‐agarofuran in methanol leads to rearrangement to the perhydroazulene system, in addition to simple double‐bond migration to β‐agarofuran. This rearrangement apparently proceeds through a carbonium‐ion‐like intermediate, whereas conventional generation of a carbocation leads only to opening of the oxide ring without rearrangement.
Synthese von Humaninsulin. II. Aufbau des cyclischen Fragments A(1–13)
Authors: Sieber Peter , Kamber Bruno , Eisler Karel , Hartmann Albert , Riniker Bernhard , Rittel Werner 
Published: December 2004

Synthesis of human insulin. II. Preparation of the A(1–13) fragment.The present report gives a detailed account of the synthesis of the protected tridecapeptide A(1–13), BocGlyIleValGlu(OBut)Gln Ser(But)LeuOH (20), an essential intermediate in the recently published total synthesis of human insulin [1]. The main feature in the synthesis of 20 was the specific formation of a disulfide bond between A6 and A11 in the presence of an additional cysteine residue (A7). The selective ring closure was accomplished with the segment A(6–13), HCys(Trt)Cys(Acm)Thr(But)Ser(But)IleCys(Trt)Ser(But)LeuOH (18), which was obtained by way of conventional synthesis routes. Treatment of 18 with iodine in trifluoroethanol formed the desired disulfide bridge from the two S‐trityl‐cysteine residues without affecting the S‐acetamidomethyl‐protected cysteine A7. A final azide coupling with the N‐terminal derivative A(1–5) (3) provided the tridecapeptide fragment 20 as a crystalline compound.
CRYPTATES XIX. Ligands polyaza‐polyoxa‐macrobicycliques: Synthèse et complexes métalliques
Authors: Lehn Jean‐Marie , Montavon François 
Published: December 2004

Polyaza‐polyoxa macrobicyclic ligands: its synthesis and metal complexes.The synthesis of the polyaza‐polyoxa macrobicyclic ligands 1–4 is described. They form complexes with a variety of metal cations, transition metal cations as well as alkali and alkaline‐earth cations. These complexes may be formulated as cation inclusion complexes, cryptates, in which the cation is contained in the intramolecular cavity. The properties of the complexes are described. An especially interesting feature is that these ligands, polymines of macrobicyclic topology, provide a means of trapping transition metal cations inside a molecular cavity; thus they impose coordination geometries and may modify the spectral and redox properties of the cations.