The heterobimetallic complexes [MPd(PPh3)(CC-Ph)(CO)3(è5-C5-C5H2Ph2(PPh2)] (5a, M ) Mo; 5b, M ) W) convert under chromatography to diastereomeric mixtures of the new trimetallic clusters [Pd{M(CO)3(è5-C5H2Ph2(PPh2)}2] (M) Mo, 9a; W, 9b), which contain a linear M-Pd-M array clamped between two (diphenyl)cyclopentadienyl-diphenylphosphino ligands. Diastereomeric pure forms of both trimetallic clusters 9a,b were obtained by fractional crystallization procedures, and the molecular structures of rac-9a and rac-9b were determined by single-crystal X-ray diffraction analyses. The trimetallic complexes 9a,b have been found to be intermediates in coupling reactions between M-I moieties and Bu3Sn-CC-Ph, to form metallacetylides M-CC-Ph. Independent high-yield synthetic routes to 9a,b have been developed.
Synthesis and Characterization of Trimetallic Complexes Containing M-Pd-M Arrays (M=Mo. W) and Their Relevance in the Palladium-Catalyzed Metal-Carbon Bond Formation
RICCI, ANTONELLA;LO STERZO, CLAUDIO;
2002-01-01
Abstract
The heterobimetallic complexes [MPd(PPh3)(CC-Ph)(CO)3(è5-C5-C5H2Ph2(PPh2)] (5a, M ) Mo; 5b, M ) W) convert under chromatography to diastereomeric mixtures of the new trimetallic clusters [Pd{M(CO)3(è5-C5H2Ph2(PPh2)}2] (M) Mo, 9a; W, 9b), which contain a linear M-Pd-M array clamped between two (diphenyl)cyclopentadienyl-diphenylphosphino ligands. Diastereomeric pure forms of both trimetallic clusters 9a,b were obtained by fractional crystallization procedures, and the molecular structures of rac-9a and rac-9b were determined by single-crystal X-ray diffraction analyses. The trimetallic complexes 9a,b have been found to be intermediates in coupling reactions between M-I moieties and Bu3Sn-CC-Ph, to form metallacetylides M-CC-Ph. Independent high-yield synthetic routes to 9a,b have been developed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.