A NEW SYNTHETIC ROUTE TO FUNCTIONALLY-SUBSTITUTED (ETA(5)-CYCLOPENTADIENYL)DICARBONYLIRIDIUM COMPOUNDS

A series of functionally substituted (eta(5)-cyclopentadienyl)dicarbonyliridium compounds have been prepared from reactions of the corresponding substituted cyclopentadienyl-sodium, -lithium, or -thallium reagents with chlorodicarbonyl(pyridine)iridium. Ring-substituted compounds synthesized by this route include chloro, benzyl, pentabenzyl, acetyl, carbomethoxy, methyl, benzoyl, trimethylsilyl, cyano, dimethylamino, tetraphenyl, dimethylaminoethyl, (tetramethyl)dimethylaminoethyl, methoxyethyl and pentamethyl. The symmetric and asymmetric carbonyl stretching frequencies as well as the C-13 NMR chemical shifts of the carbonyl substituents have been correlated with various Hammett substituent parameters.