Jörg Jeske

Iodophosphane Selenides: Building Blocks for Supramolecular Soft–Soft Chain, Helix, and Base‐Pair Arrays

A novel type of P=Se⋅⋅⋅I−P bridging is found in the solid-state structures of iodophosphane selenides. These molecules can be viewed as new building blocks for the design of directed donor–acceptor interactions (see diagram) within chains, helices and “soft–soft” base pairs.

Synthesis and Spectroscopic Data ofpara-Substituted (3-Phenyl-2H-azaphosphirene)tungsten Complexes

High-yield synthesis of para-substituted pentacarbonyl(3-phenyl-2H-azaphosphirene)tungsten complexes is reported, using a multi-step rearrangement reaction. Spectroscopic and mass-spectrometric data of these heterocyclic complexes are discussed; the 31P-NMR-chemical shifts clearly reflect the electronic influence of the para-phenyl substituents and the correlation with Hammett σp-constants is almost linear.

Novel trichlorosilylation and trichlorogermylation of a P-chlorophosphaalkene leading to functionally substituted diphosphenes

The reactions of P-chlorobis(trimethylsilyl)methylenephosphane with hexachlorodisilane or with dichlorogermylene-dioxane afford the new Si-functionalised ditrisyldiphosphene derivative [(Me 3 Si) 2 (Cl 3 Si)CP] 2 and the related trichlorogermyl diphosphene [(Me 3 Si) 2 (Cl 3 Ge)CP] 2

Synthesis and structure of the first trans-1,2-dihydro-1,2,3-triphosphete–tungsten complex

Thermal decomposition of the 2H-azaphosphirene complex 1 in the presence of kinetically stabilised phosphalkynes 2a,b yields the 1H-diphosphirene complex 4a and the 1,2-dihydro-1,2,3-triphosphete complex 5; for the latter the overall reaction may be described as an insertion of a phosphanediyl complex into a ring bond of a transiently formed 1H-diphosphirene complex, with loss of one pentacarbonyltungsten moiety.

Novel Mesityltellurium Cations from Selenenation and Tellurenation Reactions of Dimesityl Telluride in the Presence of the Br2/AgSbF6 Reagent

The reaction of dimesityl telluride (2) with bis(pentafluorophenyl) diselenide (1), Br2 and AgSbF6 provides small amounts of crystalline [Mes2TeSeC6F5][SbF6] (3). The main products, however, are [Mes2TeTeMes][SbF6] (4) and MesSeC6F5 (5). Reactions of 2 with Br2 and AgSbF6 provide − depending on the stoichiometric ratio − 4 and [Mes3Te][SbF6] (6) or [Mes2TeBr][SbF6] (7). 2, Mes2Te2, Br2 and AgSbF6 provide 4 in a fair yield. Addition of 2 to 4 leads to the tritellurium salt [Mes5Te3][SbF6] (8). Cation−anion interactions due to the α-heteroatom electrophilicity of RSe-, RTe- and Br-substituted telluronium salts are followed by structure determinations of 3, 4, 6, 7 and 8 and by Raman-spectroscopic observations of the Te−Te vibrations in compounds 4 and 8.

Stereochemically defined metal carbene complexes as chemical probes for studies of the ring formation of 2H-azaphosphirene complexes

Strong evidence for a strictly intramolecular rearrangement process leading to 2 H -azaphosphirene complex 4 was obtained by reactions of {[amino(phenyl)carbene]pentacarbonyltungsten(0)} ( 1 ) with [bis(trimethylsilyl)methylene]chlorophosphane ( 2 ) and triethylamine under CO atmosphere; the byproducts, dinuclear carbene complexes 3a , b , were obtained and characterized as E , E - and E , Z -isomers. Reaction of a 5:2 mixture of complexes 3a , b with triethylamine in dichloromethane afforded 2 H -azaphosphirene complex 4 and another product 5 , which could not be isolated, but showed 31 P-NMR characteristics of a σ 4 λ 5 -phosphorus center possessing a P–H function. { cis -[ethoxy/amino(aryl)carbene](triorganylphosphane)chromium(0)} and -tungsten(0) complexes 6a , b , 7a , b and 11 , 12 were synthesized, 6a and 7b additionally characterized by X-ray crystallography, and reacted also with methylene(chloro)phosphane 2 in the presence of triethylamine, thus yielding cis -2 H -azaphosphirene triorganylphosphane complexes 8a , b and 13a , b , which were unambiguously confirmed by NMR spectroscopy. The latter reactions proceeded with cis -stereospecificity. Significant chiral induction was not observed in the reaction leading to 13a , b , and racemization occured, most probably, at the phosphorus of the 2 H -azaphosphirene complex. These results provide strong evidence for non-participation of the metal atom center in the ring-closure process giving the three-membered 2 H -azaphosphirene ring system.

Syntheses, Structures, and Reactions of C-Methoxycarbonyl-Functionalized Small- and Medium-Sized P-Heterocycle Complexes

Thermal ring-opening of [{2-bis(trimethylsilyl)methyl-3- phenyl-2H-azaphosphirene-ĸP}pentacarbonyltungsten(0)] (8a) in the presence of dimethyl acetylenedicarboxylate (DMAD) led to the 2,3-bifunctionalized 1H-phosphirene complex 9a and the 4-phenyl-substituted 2H-1,2-azaphosphole complex 10a, the latter as a by-product. If a small amount of benzonitrile was added, complex 10a was obtained as the main product, along with a small amount of the decomplexed 2H-1,2-azaphosphole 11, which could not be isolated. Reaction of complex 10a with elemental sulfur furnished the corresponding PV sulfide 13. When the ring-opening of complex 8a was performed in the presence of two equivalents of DMAD and two equivalents of dimethyl cyanamide, we obtained the 4-dimethylamino-substituted 2H-1,2-azaphosphole complex 10b, together with the diastereomeric Δ3-1,3,2-oxazaphospholene complexes 14a,b. On reaction of [{2-pentamethylcyclopentadienyl-3-phenyl-2H-azaphosphirene-ĸP}pentacarbonyltungsten(0)] (8b) and DMAD in toluene, the corresponding 1H-phosphirene complex 9b was only formed as a transient species and the P-coordinated P,C-cage compound 15 was the final product. Using benzonitrile as solvent, the 4-phenyl-substituted 2H-1,2-azaphosphole complex 10c was obtained, together with the 7-aza-1-phosphanorbornadiene complex 16, the latter through partial decomposition of 10c coupled with rearrangement and a Diels–Alder reaction; the ratio 10c/16 was found to depend strongly on the molar ratio of complex 8b to DMAD. A cycloaddition reaction of the 2,3-bifunctionalized 1H-phosphirene complex 9a with 2,3-dimethylbutadiene furnished the bicyclic phosphirane complex 19, along with a small amount of the noncoordinated bicyclic phosphirane 20. Reaction of complex 9a with diethylamine yielded the phosphirane complex 21 as a 1,2-addition product, the diorganophosphane complex 22 through ring-opening of 9a, and the 3,4-functionalized 1,2-dihydro-1-phosphet-2-one complex 23 through an unprecedented ring-expansion reaction; the products 21, 22, 23 were formed in a ratio of ca. 1:1:1. The structures of the 1H-phosphirene complex 9a, the 4-dimethylamino-substituted 2H-1,2-azaphosphole complex 10b, the bicyclic phosphirane complex 19, the phosphirane complex 21, and the 1,2-dihydro-1-phosphet-2-one complex 23 have been determined by single-crystal X-ray diffraction analysis.

Synthese und Strukturen von N-Bis(diisopropylamino) phosphanyl-substituierten Aminocarbenkomplexen der Metalle Chrom, Molybdän und Wolfram

Abstract Aminocarbene complex anions [(CO)5MC(NH)R]− (M = Cr, Mo, W; R = Me, Ph) (1a–f), generated in situ by reaction of their conjugate acids with n-BuLi or MeLi, react with bis(diisopropylamino)chlorophosphane (2) to give lithium chloride and N-phosphanylsubstituted metal—carbene complexes [(CO)5M C(N(H)PR′2)R] (R′ = N′Pr2; R = Me, Ph) (3a–f), the first derivatives of this class of compounds. X-ray structure analysis of the chromium derivatives (3a: R = Me; 3d: R = Ph) and of the molybdenum complex (3b: R = Me) reveal M C(R) N units with structural data typical of both aminocarbene and iminiumacylmetallate complexes.

Coordination and oxidation of phosphine selenides with iodine: from cation pairs [(R3PSe)2I+]2 to (iodoseleno)phosphonium ions [R3PSeI]+ existing as guests in polyiodide matrices

An X-ray crystallographic study of adducts of trialkylphosphine selenides with >1 equivalent of diiodine reveals that solid But3PSeI3 consists of cation pairs [(But3PSe)2I+]2 intercalated between I5– layers and that solid R2R′PSeI7 (R = But or Pri, R′ = Pri) contains [R2R′P–Se–I]+ cations with weak secondary I‥I interactions to polyiodide networks.

Easy access to C,C′-bifunctionalized 1H-phosphirene–tungsten complexes: evidence for ambiphilic reaction behaviour of a phosphanediyl–tungsten complex

The 2H-azaphosphirene–tungsten complex 1 reacts with ethoxyacetylene 2a or dimethyl acetylenedicarboxylate 2b to yield C,C′-bifunctionalized 1H-phosphirene–tungsten complexes 4a,b; compounds 4a,b are characterized by NMR spectroscopy (13C, 31P) and complex 4a by single-crystal X-ray diffraction.