REACTION OF CS2 WITH A LIGAND-BRIDGED DICOBALT COMPLEX - CRYSTAL AND MOLECULAR-STRUCTURES OF [CO2(MU-PPH2CHC(SIME3)C(O)CS)(MU-PPH2S)(CO)3] AND [CO2(MU-PPH2CHCPHCS)(MU-PPH2S)(CO)3]

Thermolysis of [Co2{mu-PPhCHCRC(O)}(mu-PPh2)(CO)2] (R = SiMe3 1a or Ph 1b) in CS2 affords the complexes [Co2{mu-PPhCHCRC(O)CS}(mu-PPh2S)(CO) 3] (R = SiMe3 2a or Ph 2b) in ca. 40-50% yield. In the case of 1b a co mplex with the formula [Co2(mu-PPh2CHCPhCS)(mu-PPh2S)(CO)3] 3b was als o isolated in ca. 8% yield. X-Ray diffraction studies on complexes 2a and 3b reveal in both cases that cleavage of a carbon-sulfur bond in a CS2 molecule and insertion of the resulting CS and S fragments into r espectively Co-C and Co-P bonds have occurred. In each case also the c arbon-carbon double bond of the metallacyclic bridging ligand in la an d lb has been displaced from its co-ordination to cobalt. The reaction s of 2a and 2b with organophosphites and isocyanides lead to monosubst ituted products.