Chiral and achiral phosphine derivatives of alkylidyne tricobalt carbonyl clusters as catalyst precursors for (asymmetric) inter- and intramolecular Pauson-Khand reactions.
Phosphine derivatives of alkylidyne tricobalt carbonyl clusters have been tested as catalysts/catalyst precursors in intermolecular and (asymmetric) intramolecular Pauson-Khand reactions. A number of new phosphine derivatives of the tricobalt alkylidyne clusters [Co3(micro3-CR)(CO)9] (R = H, CO2Et) were prepared and characterised. The clusters [Co3(micro3-CR)(CO)9-x(PR'3)x] (PR'3 = achiral or chiral monodentate phosphine, x = 1-3) and [Co3(micro3-CR)(CO)7)(P-P)] (P-P = chiral diphosphine; 1,1'- and 1,2-structural isomers) were assayed as catalysts for intermolecular and (asymmetric) intramolecular Pauson-Khand reactions. The phosphine-substituted tricobalt clusters proved to be viable catalysts/catalyst precursors that gave moderate to very good product yields (up to approximately 90%), but the enantiomeric excesses were too low for the clusters to be of practical use in the asymmetric reactions.
Moberg
Viktor
V
Inorganic Chemistry Research Group, Chemical Physics, Center for Chemistry and Chemical Engineering, Lund University, Box 124, SE-221 00, Lund, Sweden.
Mottalib
M Abdul
MA
Sauer
Désirée
D
Poplavskaya
Yulia
Y
Craig
Donald C
DC
Colbran
Stephen B
SB
Deeming
Antony J
AJ
Nordlander
Ebbe
E