Direct carbonylation of (alpha-siloxybenzyl)iron complexes In(CO)2FeCH
(OSiMe3)R (R = Ph, p-OCH3Ph) under mild reaction conditions (1 atm, am
bient temperature) afforded the acyl compounds In(CO)2FeCOCH(OSiMe3)R
in very good yield. The (alpha-methoxybenzyl)iron complex ln(CO)2FeCH(
OCH3)Ph was also carbonylated in fair yield. Carbon monoxide insertion
was determined to be a function of the combined effects of the indeny
l (In) ligand, a phenyl group, and an alpha-siloxy/alkoxy substituent.
Proof of this was demonstrated by failure of the cyclopentadienyl (Cp
) analog CP(CO)2FeCH(OSiMe3)Ph, the methyl substituted complex In(CO)2
FeCH(OSiMe3)CH3, and the benzyl complex In(CO)2FeCH2Ph to undergo carb
onylation under similar reaction conditions.