INSERTIONS OF UNACTIVATED OLEFINS INTO THE HYDROSULFIDO LIGAND OF A CATIONIC CYCLOPENTADIENYLMOLYBDENUM COMPLEX

The cationic complex [(CpMo)2(S2CH2)(µ-S)(µ-SH)]SO3CF3 ([1]SO3CF3) has been reacted with a series of terminal and internal olefins to form the cationic product in which the olefin has inserted into the S‒H bond of the bridging ligand. The reaction has been found to be reversible for most olefins. The regiochemistry of the insertion reaction has been studied, and relative rates of insertion have been determined as olefin substituents were varied. For reactions involving internal olefins, the kinetic insertion products were found to rearrange to more stable products. A mechanism for the olefin insertion reaction has been proposed that involves attack of an electrophilic sulfido ligand in 1 on the more electron-rich carbon of the olefin. Secondary products have been isolated from many of the reaction solutions and characterized by spectroscopic data. The secondary products result from air oxidation of 1 and further reaction of this oxidized derivative with olefins. © 1990, American Chemical Society. All rights reserved.