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A series of N,P,P‐trisubstituted aminophosphanes react with diphenylcyclopropenone to afford an easily separable mixture of two diastereomeric α,β‐diphenyl‐β‐phosphinoyl carboxamides in good yields. X‐ray crystal structures reveal that these compounds associate into dimers, formed from two enantiomeric units linked by two bifurcated hydrogen bonds, whereby the oxygen atom of the phosphoryl group acts as a dual acceptor for the vicinal NH and CH of a carbonyl group of a neighbouring molecule. Studies on the interconversion between diastereomeric phosphinoyl carboxamides in basic solution show that the thermodynamically most stable isomer depends on the nature of the substituent at the nitrogen atom. Simple computational calculations explain this phenomenon.

The Michael-type addition of a range of amines to the C&z.dbd;C bond of P,P,P-diphenylvinyl iminophosphoranes yielded a new class of N,N-bidentate ligands R1–N&z.dbd;P(Ph₂)CH₂CH₂–NR2R3 (2). These mixed nitrogen–nitrogen donor ligands react with stoichiometric amounts of PdCl₂(PhCN)₂ to give σN,σN-palladium complexes 3 containing an iminophosphorane moiety. From primary amines and two vinyl iminophosphorane units, either identical or different, the new terdentate ligands R1–N&z.dbd;P(Ph₂)CH₂CH₂–N(R3)–CH₂CH₂P(Ph₂)&z.dbd;N–R2 (4), where R1 = R2 or R1 ≠ R2, could be efficiently synthesized. Reaction of these ligands with 1.5 equiv. of PdCl₂(PhCN)₂ yielded the cationic complexes 5 with the ligands coordinating in a N,N',N'-terdentate fashion. Additionally, by the use of other nucleophiles such as diphenylphosphane and thiophenol this methodology has been applied to the synthesis of the new N,P-(R–N&z.dbd;P(Ph₂)CH₂CH₂PPh₂) (9) and N,S-bidentate (R–N&z.dbd;P(Ph₂)CH₂CH₂SPh) (10) ligands, respectively, and of their corresponding Pd(ii) complexes (11 and 12). All compounds have been characterized by spectroscopic methods and the X-ray crystal structures of 3c, 5b and 11b are reported.

Asymmetrically substituted bis(iminophosphoranes) derived from 1,2- bis(diphenylphosphino)ethane are prepared by Michael-type addition of easily available N,P,P-trisubstituted aminophosphanes to P-vinyl iminophosphoranes. Similarly P-alkylations of aminophosphanes with P-vinyl phosphane oxides and sulfides are also disclosed.

N-Aryl-P,P-diphenyl-P-(diphenylphosphinoyl)methyl-λ5-phosphazenes undergo smooth acid-catalysed hydrolysis with concomitant PC bond fission yielding N-aryl-P,P-diphenylphosphinamides and diphenylmethylphosphane oxide. A tentative mechanistic explanation is given.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

For Abstract see ChemInform Abstract in Full Text.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.