A first example of the faster migration of phenyl over methyl: kinetics of the reaction of triphenylphosphine with organo-carbonyl-iodo-rhodium(III) complexes

Abstract

The reactions of PPh₃ with [C₅Me₅RhR(CO)l] to yield [C₅Me₅Rh(COR)(PPh₃)l], proceed by a ‘direct attack’ mechanism in less-polar solvents; the migrations are favoured by electron releasing R, but follow organic rearrangements in that phenyl migrates more rapidly than methyl.