bluuebunny/crossref_metadata_2025_split huggingface dataset:
Halogen(Silyl)phosphane – Synthese und Eigenschaften
Authors: Treubel Rainer , Niecke Edgar 
Published: July 2007

Halogeno(si1yl)phosphanes ‐ Synthesis and PropertiesBis(trimethylsilyl)phosphanes 1a–d react with hexachloroethane to give chloro(trimethylsily)phosphanes 2a–d. The decomposition of these compounds to cyclophosphanes is found to be catalized by Lewis acids and bases. Nucleophilic substitution of the P‐chloro function of 2c leads to the bromo(9a), iodo‐ (9b) and azido derivative (10a). Methanolysis of 2a–d leads to tye secondary chlorophosphanes 11a–d.Reaction of 2a–e with chloromethylenephosphane 12a results in the formation of 1‐chlorodiphosphiranes 16a–e via a 1,2‐diphospha‐2‐propene intermediate 14. The 1‐bromo‐(19a) and 1‐iododiphosphirane 19b is accessible from 16c by exchange reaction with the corresponding halosilanes. The potential of halo(sily)phosphanes as phosphanediyl transfer reagents was unhindered in the reaction of 2c with different substituted phosphaalkenes 28a–d to the corresponding diphosphiranes 29a– d.
Synthesis and Reactivity of Chiral Rhenium Alcohol Complexes of the Formula [(η5‐C5H5)Re(NO)(PPh3)(ROH)]⊕BF4⊖
Authors: Agbossou Sénamé K. , Smith Whitney W. , Gladysz John A. 
Published: July 2007

AbstractReactions of dichloromethane complex [(η5‐C5H5)Re(NO)‐(PPh3)(ClCH2Cl)]⊕ BF4⊖ (2⊕ BF4⊖ and alcohols ROH give the title compounds [(η5‐C5H5)Re(NO)‐(PPh3)(ROH)]⊕ BF4⊖; (3⊕ BF4⊖; a: R = Me, b: Et, c: CH2Ph, d: t‐Bu) in 91–95% yields as air‐stable powders after workup. Reactions of 3a–c⊕ BF4⊖ and Et3N produce alkoxide complexes (η5‐C5H5)Re(NO)‐(PPh3)(OR) (4a–c, 80–90%), which in turn react with HBF4– OEt2 to give 3a–c⊕ BF4⊖. Reactions of 3a–c⊕ BF4⊖ and Ph3PX⊕ Br⊖ give the bromide complex (η5‐C5H5)Re(NO)‐(PPh3)(Br) (85‐98%) and alcohols ROH. 3b,c⊕ BF4⊖ and aldehydes react to give π complexes [(η5‐C5H5)Re(NO)(PPh3)(η2‐OCHR′)]⊕ BF4⊖ (>94%). Reaction of 3b⊕ BF4⊖ and HSi(OEt)3 generates the hydride complex (η5‐C5H5)Re(O)(PPh3)(H) (5, 77%). Reaction of 5 with Ph3C⊕ PF6⊖ and then ROH gives 3⊕ PF6⊖ (88–91%). NMR experiments establish the order OCHR > ROH > ROR for ligand binding energies to the rhenium fragment [(η5‐C5H5)Re(NO)(PPh3)]⊕.
Spektroskopische Studien an höheren Chromfluoriden. Zur Frage der Existenz von Chromhexafluorid, CrF6
Authors: Jacob Eberhard , Willner Helge 
Published: July 2007

Spectroscopic Studies of Higher Chromium Fluorides. Controversy over the Existence of Chromium Hexafluoride, CrP6Combustion of chromium with fluorine under various conditions led always to CrF5 as the highest chromium fluoride. The properties of pure CrF5 have been reinvestigated and IR, UV spectra of the gas‐phase molecule, and also the vapor pressure have been measured for the first time. Furthermore, it has been shown that the IR spectrum of matrix‐isolated CrF5 is identical to the IR spectrum of CrF6 quoted in the literature. It appears, that in principle the existence of CrF6 is doubtful.
Kopplung zwischen Polypyridinruthenium(II)‐ und Methylviologen‐Einheiten in π‐konjugierten Hybridsystemen
Authors: Kaim Wolfgang , Matheis Walter 
Published: July 2007

Coupling between Polypyridineruthenium(II) and Methylviologen Moieties in n‐Conjugated Hybrid SystemsComplexes between the novel 3,3′‐diazamethylviologen chelate ligands and the [Ru(bpy)2]2+ fragment were synthesized and characterized by cyclic voltammetry, electronic absorption spectroscopy, and electron spin resonance. Incorporation into a common π system results in strong electronic coupling between the 4,4′‐bipyridinium and the tris(α‐diimine) metal chelate functions with significantly altered spectroscopic properties. The isomeric complexes with 4,4′‐diquaternized 2,2′‐bipyrazine ligands exhibit smaller electronic coupling and irreversible second reduction to a non‐Kekule system which helps to understand the superior photosensitizing properties of 2,2′‐bipyrazine complexes
Dreikernige Dithiadiaza[3.3.2]cyclophan‐ene
Authors: Schmiegel Jürgen , Funke Ulrike , Mix Andreas , Grützmacher Hans‐Friedrich 
Published: July 2007

Trinuclear Dithiadiaza[3.3.2]cyclophan‐enesThe following five trinuclear dithiadiazacyclophanes have been prepared by means of the rigid‐group principle with a succinyl and dimethylmalonyl N,N′‐protecting group, respectively, and the high‐dilution technique: 2,11‐dithia‐19,20‐diaza[3.3.2]‐(1,4)(1,4)(1,4)cyclophan‐19‐ene (12), 2, 11‐dithia‐19,20‐diaza[3.3.2]‐(1,3)( 1,4)( 1,4)cyclophan‐19‐ene (13), 2,l l‐dithia‐19,20‐diaza[3.3.2]‐(1,4)(1,3)(1,3)cyclophan‐19‐ene (14), 2,11‐dithia‐19,20‐diaza[3.3.2]‐(1,3)(1,3)(1,3)cyclophan‐19‐ene (15), and 4,6‐dimethyl‐2,9‐dithia‐17,18‐diaza[2.2.2]( 1,3)(1,3)(1,3)cyclophan‐17‐ene (16). These cyclophanes contain an azobenzene moiety bridged in the case of 12 and 13 in the para‐positions by a benzene ring and two short links which forces 12 and 13 into a cis‐azo configuration. 14 – 16 are bridged in the meta‐positions of the azobenzene and can adopt a cis‐ and a trans‐azo configuration, respectively. 14 ‐ 16 are photoisomerized into the cis form by irradiation with γ = 369 nm. The isomerization back into the trans form occurs slowly thermally or rapidly by irradiation with λ = 443 nm.
Dimroth‐Umlagerung von Iminen des 1,5‐Diaminotetrazols
Authors: Moderhack Dietrich , Goos Karl‐Heinz , Preu Lutz 
Published: July 2007

Dimroth Rearrangement of Imines Derived from 1,5‐DiaminotetrazoleHeating the imines 1 in dimethyl sulfoxide (or partly in xylene) provides hydrazones such as 2. The reaction is greatly favoured by electron‐withdrawing groups attached to the imine carbon atom.
Fixierung von Harnstoffen und Thioharnstoffen auf dreikernigen Ruthenium‐Clustern: Synthese und Molekülstruktur von (μ2‐H)Ru3(CO)9(μ3‐NPhCSNHPh)
Authors: Bodensieck Ulf , Stoeckli‐Evans Helen , Süss‐Fink Georg 
Published: July 2007

Fixation of Ureas and Thioureas on Trinuclear Ruthenium Clusters: Synthesis and Molecular Structure of (μ2‐H)Ru3(CO)9(μ3‐NPhCSNHPh)Trinuclear clusters of the type (μ2‐H)Ru3(CO)9[μ3‐NRC(E)NHR] (EO, S; RH, Me, Ph) have been synthesized from Ru3(CO)12 and the corresponding ureas and thioureas, respectively. The X‐ray crystal structure analysis of the N,N'‐diphenylthiourea derivative 3 reveals the thiourea moiety to be coordinated to the trinuclear metal framework by the sulfur atom in a μ2‐like fashion and by one of the nitrogen atoms acting as a terminal ligand. While the SCN backbone has remained intact on the cluster site, one of the hydrogen substituents has been transferred from the coordinated nitrogen to the metal framework.
Die Reaktion von 3‐Borolenen mit terminalen Acetylenen: Ein neuer Zugang zu 2‐Borolenen
Authors: Herberich Gerhard E. , Wang Shaotian 
Published: July 2007

The Reaction of 3‐Borolenes with Terminal Acetylenes: A New Route to 2‐Borolenes3‐Borolenes (2,5‐dihydro‐1H‐boroles) (1a: R′H, RPh; 1b: R′H, RCy; 1c: R′Me, RPh) readily react with terminal acetylenes R″CCH (R″Bu, tBu, 1‐Cyclohexenyl, Ph, ClCH2, BrCH2) to give a variety of 3‐substituted 4‐vinyl‐2‐borolenes (2).
Synthese und Charakterisierung neuer Halogeno(methyl)arsen(V)‐Kationen: [(CH3)2AsI2]⊕ [AsF6]⊖, [CH3AsI3]⊕ [AsF6]⊖ und [(CH3)2AsF2]⊕ [AsF6]⊖
Authors: Tornieporth‐Oetting Inis , Klapötke Thomas 
Published: July 2007

Synthesis and Characterization of Novel Halogeno(methyl)arsenic(V) Cations: [(CH3)2AsI2]⊕ [AsF6]⊖, [CH3AsI3]⊕ [AsF6]⊖ and [(CH3)2AsF2]⊕ [AsF6]⊖The two new iodo(methyl)arsenic(V) hexafluoroarsenates [(CH3)2AsI2]⊕ [AsF6]⊖ (1) and [CH3AsI3]⊕ [AsF6]⊖ (2) have been prepared by direct oxidation of (CH3)2AsI or CH3AsI2 with IF in the presence of AsF5. (CH3)2AsF reacts quantitatively with F2 and AsF5 to yield [(CH3)2AsF2]⊕ [AsF6]⊖ (3). The reaction of 3 with CsF leads to the neutral compound (CH3)2AsF3 (4) and CsAsF6.
Chiral recognition of diastereomeric esters and acetals by EPR and NMR investigations
Authors: Mäurer Manfred , Stegmann Hartmut B. 
Published: July 2007

AbstractThe reaction of the racemic phenols I and II with chiral auxiliaries like the acid chloride III and particularly the lactols IV and V (Noe's reagent) leads to diastereomeric esters and acetals, respectively. The products may be synthesized either in the EPR sample tube or under preparative conditions with subsequent separation of the diastereomers by chromatographic methods. Oxidation of the phenols with lead dioxide in inert solvents provides the corresponding phenoxyls, which are investigated by EPR and ENDOR spectroscopy. The most striking features of these spectra are the differences in the β‐proton coupling constants of up to several Gauss, indicating a significant alteration of the hyperconjugation angle. These results are interpreted in terms of the population of specific conformations favored by stereoelectronic and steric interactions, which are confirmed by careful investigations of the shielding and deshielding effects in the 1H‐NMR spectra of the corresponding phenols.
Siliciumverbindungen mit starken intramolekularen sterischen Wechselwirkungen, 41. Disilen‐Additionen an die CN‐Mehrfachbindungen von Isochinolin und Dicyclohexylcarbodiimid
Authors: Weidenbruch Manfred , Lesch Axel , Peters Karl , von Schnering Hans Georg 
Published: July 2007

Silicon Compounds with Strong Intramolecular Steric Interactions, 41. ‐ Disilene Additions to the CN Multiple Bonds of Isoquinoline and DicyclohexylcarbodiimideTetra‐tert‐butyldisilene (4), generated photolytically from hexa‐tert‐butylcyclotrisilane (3), reacts with isoquinoline in a [2 + 2] cycloaddition to give the 1,2,3‐azadisiletane derivative 7, whose structure was determined by X‐ray crystallography. Photolysis of 3 in the presence of dicyclohexycarbodiimide (8), however, yields the 1,2,4‐azadisiletanimine derivative 10, presumably formed by rearrangement of an intermediate [2 + 2] addition product of 4 to one of the CN bonds of 8. The X‐ray structure analysis of 10 reveals that the four ring atoms and the exocyclic nitrogen atom lie exactly in plane. The smallest bond angles inside the ring occur at the Si atoms.
Komplexchemischer Aufbau cyclischer 1,2‐Dithiolato‐Liganden mit dem nido‐Cluster [(CO)3FeS]2. — Molekülstruktur und partielle S‐Oxidation von Hexacarbonyl(μ2‐cis‐1,2‐cyclohexandithiolato‐S,S)dieisen
Authors: Kramer Anja , Lingnau Regine , Lorenz Ingo‐Peter , Mayer Hermann August 
Published: July 2007

Complex‐Chemical Synthesis of Cyclic 1.2‐Dithiolato Ligands with the nido Cluster [(CO)3,FeS]2. — Molecular Structure and Partial S‐Oxidation of Hexacarbonyl(μ2,‐cis‐1,2‐cyclohexanedithiolato‐S,S)diironThe cyclic alkenes, dienes, and trienes C6H10, C8C14, C5H6, C8C12 and C7H8 are inserted into the S‐S bond of the nido cluster [(CO)3FeS]2 (1) by photochemically induced [2+2] cycloaddition reactions to give the complexes 2–6; thus, saturated and unsaturated cyclic 1,2‐dithiolato ligands can be selectively built onto the complex in a μ2‐bridging fashion. According to an X‐ray structure analysis, the μ2‐1,2‐cyclohexanedithiolato‐S,S complex 2a with the pseudotetrahedral skeleton [(CO)3FeS]2 crystallizes in the monoclinic space group P21/c; the S2 moiety is bridged by cyclohexane with 1,2‐cis configuration. As an example, the partial S oxidation of 2a was carried out, leading to 2b by selective transformation of one thiolato into a sulfenato function.
[2.2](2,5)Pyrimidinophanes: Synthesis and molecular structure
Authors: Eiermann Uwe , Krieger Claus , Neugebauer Franz A. 
Published: July 2007

AbstractThe title compounds 1 and 2 are synthesized by photolytic sulfur extrusion from the 2,11‐dithia[3.3](2,5)pyrimidinophane 17. The molecular structures of 1 and 2 are determined by X‐ray structure analysis and are discussed with regard to the steric strain in these molecules. Thermolysis of [(5‐methyl‐2‐pyrimidinyl]methyl]‐ or [(2‐methyl‐5‐pyrimidinyl)methyl]‐trimethylammonium hydroxide (10 or 11) does not generate 1 and 2. α‐Chlorination of 2,5‐dimethylpyrimidine (3) with N‐chlorosuccinimide provides the required precursors 4–6.
Synthese von Reinst‐Rubicen und Rubicen‐Derivaten
Authors: Sachweh Volker , Langhals Heinz 
Published: July 2007

Synthesis of Highly Pure Rubicene and Rubicene DerivativesA simple one‐step synthesis of highly pure rubicene (2) from fluorenone (1) and magnesium with 24% yield is described and compared with other preparation procedures. Mono‐ and disubstituted rubicene derivatives are prepared by electrophilic aromatic substitution.
Folgereaktionen von Sulfenen aus Sulfonylchloriden und tertiären Aminen, 2. Bildung von Episulfonen, Sulfonylsulfen — Amin‐S,N‐Addukten und Chlorsulfinen aus primären Sulfonylchloriden und tertiären Aminen
Authors: Opitz Günter , Ehlis Thomas , Rieth Karlheinz 
Published: July 2007

Secondary Reactions of Sulfenes from Sulfonyl Chlorides and Tertiary Amines, 2. — Formation of Episulfones, Sulfonylsulfene — Amine S.N‐Adducts. and Chlorosulfines from Primary Sulfonyl Chlorides and Tertiary AminesThe reaction of primary sulfonyl chlorides 1b–m with the tertiary amine bases quinuclidine, DABCO, Me3N, Et3N, Bu3N, EtiPr2N, and 1,2,2,6,6‐pentamethylpiperidine is studied in acetonitrile solution between − 40 and 80°C. The 2,3‐dialkylthiirane 1,1‐dioxides 4 (trans/cis > 1) and the alkenes 5 [(E)/(Z) > 1] are obtained in high yields with Et3N at − 40°C. The stereochemistry is influenced by the amine base B in the ring closure reaction and partially by epimerization of the episulfones 4. Hindered bases favor the cis, β‐branched sulfonyl chlorides the trans isomer. Competing formation of the sulfonylsulfene–amine S,N‐adducts 7 is only observed with quinuclidine, DABCO, and Me3N, which are also the most active amines in the epimerization of the cis‐2,3‐diarylthiirane 1,1‐dioxides 4. Methanesulfonyl chloride (1a) yields the mesylsulfene–amine S,N‐adducts 7a with Me3N and Et3N in MeCN, but thiirane 1,1‐dioxide (4a) with EtiPr2N in MeCN or with Et3N in Et2O. Formation of chlorosulfines 10 is favored by higher temperature (T > 20°C), hindered amine bases and β‐branched sulfonyl chlorides. Isolation of 10g and 10h in high yields shows that tert‐alkylchlorosulfines are rather stable sulfines.
Synthetic pathways to disilylmethane, H3SiCH2SiH3, and methyldisilane, CH3SiH2SiH3
Authors: Zech Joachim , Schmidbaur Hubert 
Published: July 2007

AbstractDisilylmethane is available in a four‐step synthesis starting with phenylsilane. This is converted into chlorophenylsilane by HCl/AlCl3. The reaction of PhSiH2Cl and dibromomethane with magnesium in tetrahydrofuran affords bis(phenylsilyl)‐methane, which yields bis(bromosilyl)methane by treatment with anhydrous hydrogen bromide. (BrH2Si)2CH2 is converted into disilylmethane by reduction with LiAlH4 in a two‐phase system using a phase‐transfer catalyst. ‐ Methyldisilane is available by alkylation of a monohalodisilane, XSi2H5 (X  Cl, Br), with methyllithium in a high‐boiling ether or by silylation of bromomethylsilane with silylpotassium. Due to secondary silylation reactions the overall yields of methyldisilane are low in all cases.
Synthesis of acetyl‐substituted heterocyclic ketene aminals and their deacetylation reaction
Authors: Wang He‐Ting , Wang Xiao‐Jun , Huang Zhi‐Tang 
Published: July 2007

AbstractThe acetyl‐substituted heterocyclic ketene aminals 3 — 6 were synthesized by the reaction of ketene dithioacetals 2 with diamines. The deacetylation of heterocyclic diacetyl keteneaminals by alkali was studied, and the corresponding monoacetyl derivatives were obtained.
Geminale Substituenteneffekte, 4. Abhängigkeit des inversen anomeren Effektes geminaler Nitril‐Gruppen von der Struktur
Authors: Beckhaus Hans‐Dietr , Dogan Barbara , Pakusch Joachim , Verevkin Sergei , Rüchardt Christoph 
Published: July 2007

Geminal Substituent Effects, 4. — The Dependence of the Inverse Anomeric Effect of Geminal Cyano Groups on the StructureThe heats of combustion and the heats of sublimation of malodinitrile (1a), ä‐alkyl‐ (1b,c) and å, å‐dialkylmalodinitriles (1 d ‐f) have been determined. From the obtained standard heats of formation group increments for CH2[CN]2], CH[(CN)2 Cl and C[CN)2C2] group are deduced. The comparison of their values with corresponding increments for monocyano alkanes reveals a synergetic destabilisation by two geminal cyano substituents of 11.5, 9.0 and 6.6 kcal/mol, respectively. Thus, this inverse anomeric effect decreases by increasing alkyl substitution.
SF5‐substituierte Ketene
Authors: Bittner Jürgen , Seppelt Konrad 
Published: July 2007

SF5‐Substituted KetenesKetenes F5S ‐ CR  C  O [R  H, CH3, C1. Br (2a ‐ d )] are pre‐pared by dehydration from the acids F5S ‐ CHR ‐CO2H (1a‐d), or in the case of R  CH3 (b) also by halogen elimi‐ nation with mercury. These ketenes exhibit remarkable sta‐bility, increasing in the sequence R  H, CH3, C1, Br. They undergo addition reactions across the C  C double bond in known fashion. The isomerization reaction of F5SCH  C  O (2a) to F,SCHCOF is not shown by any of the other ke‐tenes.
Synthese und Photolyse von 1,4,4‐Trialkyl ‐4,5‐dihydro‐5‐imino ‐1H‐1,2,3‐triazolen. — Regio‐ und diastereoselektive Bildung von (Z)‐Aziridiniminen
Authors: Quast Helmut , Regnat Dieter 
Published: July 2007

Synthesis and Photolysis of 1,4,4‐Trialkyl‐4,5‐dihydro‐5‐imino‐1H‐1,2,3‐triazoles. — Regio‐ and Diastereoselective Formation of (Z)‐AziridiniminesThe novel 5‐iminodihydro‐1,2,3‐triazoles 14 are synthesized from the 5‐isopropylidenedihydrotetrazole 11 through a ring transformation involving cycloaddition and cycloreversion of alkyl azides 12. Thus, [3 + 21 cycloaddition of 11 and 12 pro‐ duces high yields of the spiro compounds 13. On thermolysis at 120‐ 130°C, the latter undergo clean [3 + 2] cycloreversion into methyl a i d e (12a) and the iminodihydro‐1,2,3‐triazoles 14, which exist as mixtures of diastereomers, e.g. (E)‐/(Z)‐14a = 955, or as a single stereoisomer (E)‐14c. When toluene solutions of 14 are irradiated (≥ 1 280 mm) at ‐ 60°C, the configuration of the products is under kinetic control. Irradiation of 14a affords a quantitative yield of the aziridinimines (E)‐and (Z)‐15a (11:89) besides molecular nitrogen. In order to allow the distinction between the least‐motion and the non‐least‐motion path of product formation, the photolysis of iminodihydro‐1,2,3‐triazoles is studied which are labelled at N‐1 by a deuterated methyl group (14b) or a neopentyl group (14c). Neither photolysis (λ ≥280 nm) nor heating to 120 to 130°C induces any scrambling of the alkyl groups attached to N‐1 and the exocyclic nitrogen atom of 14b and c. The major product from (E)‐/(Z)‐14b (84%) is formed by the non‐least‐motion path leading diastereoselectively to (Z)‐15 b, while the least‐motion products (E)‐ and (Z)‐17b (16%) exhibit a diastereo‐meric ratio of 3: 1. Very similar results are obtained on photolysis of (E)‐14c, except that the least‐motion product (15%) arises only in a single configuration [(E)‐l7c]. In the non‐least‐motion products (Z)‐15b, c, the geometry of the MeN‐CN???R group, fixed by the ring in 14b, c, is completely retained. Therefore, the (Z) diastereoselectivity is interpreted in terms of a one‐bond cleavage leading to diazenyl‐1,3‐diazaallyl diradicals 22 having lifetimes too short for changes of their configuration which is determined by the structure of the precursor.
Wasserstoffübertragungen, 16. Freie 1‐Phenylallyl‐Kationen bei der Aromatisierung von Dihydronaphthalinen mit Triphenylmethyl‐tetrafluoroborat
Authors: Giese Georg , Heesing Albert 
Published: July 2007

Free 1‐Phenylallyl Cations in the Aromatisation of Dihydronaphthalenes by Triphenylmethyl TetrafluoroborateThe aromatisation of 1,2‐ and 1,4‐dihydronaphthalenes by trityl cations proceeds by a common intermediate, the 1‐phenylallyl cation 4 of sufficient lifetime to allow for both side reactions and loss of stereoselectivity. The primary hydride abstraction occurs with moderate tunneling participation and in a linear geometry of the three participating atoms as shown by the temperature dependence of the primary isotope effect.
Stereoselective synthesis of alcohols, XXXIV. Towards an understanding of cram/anti‐cram selectivity on addition of crotylboronates to α‐methylbutyraldehyde
Authors: Hoffmann Reinhard W. , Brinkmann Heinrich , Frenking Gernot 
Published: July 2007

AbstractThe diastereoselectivity on addition of γ‐substituted allylboronates to α‐methylbutyraldehyde (9) did not depend on the size of the substitutent in the reagent, but only on its location in the Z or E position. This finding required a reinterpretation of the reasons for the attendant reversal in diastereoselectivity. New hypotheses are presented based on force‐field calculations on model structures for the transition states.
Radical ions and photochemical charge transfer phenomena, 28. 1,1′‐Binaphthalene‐2,2′‐dicarbonitrile in photochemically sensitized enantiodifferentiating isomerizations
Authors: Vondenhof Martin , Mattay Jochen 
Published: July 2007

AbstractThe synthesis of optically active (+)‐ and (‐)‐1,1′‐binaphthalene‐2,2′‐dicarbonitrile (1) is described as well as its application in photoinduced electron transfer (PET) dimerizations and isomerizations.
Derivate des Borols, XVII {η5‐[1‐(Diisopropylamino)borol]}metall‐Komplexe: Synthesen, Protonierung, interne Rotation
Authors: Herberich Gerhard E. , Negele Michael , Ohst Holger 
Published: July 2007

Derivatives of Borole, XVII1). – {η5‐[1‐(Diisopropylamino)borole]}metal Complexes: Syntheses, Protonation, Internal RotationNew complexes M(CO)4L (M = Cr, W), cis‐M(CO)2L2 [M = Mo, W (not isolated)], and (COD)NiL have been prepared from the Diels‐Alder dimer L2, where L is 1‐(diisopropylamino)borole, C4H4BNiPr2. Complexes of L can be protonated at the nitrogen atom to give stable salts such as [Cr(CO)4(LH)]BF4, [Fe(CO)3(LH)]BF4, [(C6Me6)Ru(LH)]BF4, and [CpCo(LH)]BF4; B — N bond dissociation is not observed. Barriers to internal rotation have been determined by variable temperature NMR spectroscopy for Cr(CO)4L, (COD)NiL, and NiL2. Three processes have been identified: rotation of the NiPr2 group around the B — N bond, gear‐mesh rotation of the isopropyl groups around the C — N bonds, and rotation of L with respect to the counter ligands.
(Perfluoralkyl)(dimethylamino)sulfonium‐hexafluoroarsenate
Authors: Erhart Markus , Rüdiger  , Pauer Frank , Stalke Dietmar , Sheldrick George M. 
Published: July 2007

(Perfluoroalkyl)(dimethylamino)sulfonium HexafluoroarsenatesMeN = S(CF3)2 (5) is alkylated by Me3O⊕ AsF⊖6 to Me2N‐S(CF3)⊕2 AsF⊖6 (4). From 5 and MeOSO⊕ AsF⊖6 (6) MeOS(O)‐N(Me)S(CF3)⊕2 AsF⊖6 (7) is formed as a relatively stable primary product. Decomposition of 7 gives the expected 4 only in poor yield. Nucleophilic substitution of the sulfur‐bonded fluorine in CF3SF⊕2 AsF⊖6 (8) by Me3SiNMe2 yields CF3S(NMe2)⊕2 AsF⊖6 (9). Similarly, (CF3)2CFSF⊕2 AsF⊖6 (10) reacts with dimethyl(trimethylsilyl)amine to give (CF3)2CFS(NMe2)⊕2 AsF⊖6 (11). The structures of 4 and 9 are elucidated by X‐ray analyses, and the influence of the substituents on the bonding is discussed.