Preparation of (eta(5)-RC5H4)(2)Mo-2(CO)(2)(mu-PhS)(2) (R=H, MeCO) by the reaction of [eta(5)-RC5H4Mo(CO)(2)](2) with (mu-PhS)(2)Fe-2(CO)(6). Crystal structures and acetyl transformation reactions of two isomers trans/anti- and trans/syn-(eta(5)-MeCOC5H4)(2)Mo-2(CO)(2)(mu-PhS)(2)

Reaction of Mo=Mo triply bonded complexes [eta(5)-RC5H4Mo(CO)(2)](2) with the Fe/S butterfly compound (mu-PhS)(2)Fe-2(CO)(6) in refluxing xylene gives two corresponding Mo=Mo doubly bonded complexes (eta(5)-RC5H4)(2)Mo-2(CO)(2)(mu-PhS)(2). Each of the complexes consists of two isomers, namely trans/anti and trans/syn, in terms of the relative arrangement of the RC5H4 and CO ligands and the mutual orientation of the phenyl groups on the bridging sulfur atoms. The two isomers with R = MeCO are convertible to each other in xylene at reflux and have been crystallographically determined by X-ray diffraction. Further reactions of the R = MeCO complex with NaBH4 and MeMgI afford two corresponding functional hydroxyl derivatives [eta(5)-MeCH(OH)C5H4](2)Mo-2(CO)(2)(mu-PhS)(2) and [eta(5)-Me2C(OH)C5H4](2)Mo-2(CO)(2)(mu-PhS)(2).