Tungsten complexes of aromatic and aliphatic thioaldehydes

Autor:	Wolfdieter A. Schenk, Birgit Vedder, Christian Eichhorn
Rok vydání:	2004
Předmět:	Nucleophilic addition Stereochemistry Electrophilic addition Hydride Alkylation Metathesis Medicinal chemistry E-Z notation Inorganic Chemistry chemistry.chemical_compound chemistry Thioether Materials Chemistry Trifluoroacetic acid Physical and Theoretical Chemistry
Zdroj:	Inorganica Chimica Acta. 357:1886-1896
ISSN:	0020-1693
Popis:	Reaction of PPN[W(CO)3(R2PC2H4PR2)(SH)] (PPN=Ph3PNPPh3; R=Me, 1; R=Ph, 2) with aromatic aldehydes in the presence of trifluoroacetic acid gave tungsten complexes of thiobenzaldehydes mer-[W(CO)3(R2PC2H4PR2)(η2-SCHR′)] (R=Me, 3a–3f; R=Ph, 4a–4e) in high yields. Analogous complexes of aliphatic thioaldehydes mer-[W(CO)3(Me2PC2H4PMe2)(η2-SCHR′)] (3g–3l) could only be obtained from the highly electron-rich thiolate complex 1. The structure of 3i (R′=i-Bu) was determined by X-ray crystallography. In solution the complexes 3 and 4 are in equilibrium with small quantities of their isomers fac-[W(CO)3(R2PC2H4PR2)(η2-SCHR′)]. Reaction of complexes 3 with dimethylsulfate followed by salt metathesis with NH4PF6 gave the alkylation products mer-[W(CO)3(Me2PC2H4PMe2)(η2-MeSCHR′)]PF6 (5a–5l) as mixtures of E and Z isomers. The methylated thioformaldehyde complex mer-[W(CO)3(Me2PC2H4PMe2)(η2-MeSCH2)]PF6 (5m) was prepared similarly. Nucleophilic addition of hydride (from LiAlH4) to 5 initially gave thioether complexes mer-[W(CO)3(Me2PC2H4PMe2)(MeSCH2R′)] (mer-6) which rapidly isomerized to fac-[W(CO)3(Me2PC2H4PMe2)(MeSCH2R′)] (fac-6).
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::f5007dfbe126db88cd97eabd0b368fa3 https://doi.org/10.1016/j.ica.2003.11.032 Zobrazit plný text záznamu Full Text from ScienceDirect