A reversible metal framework rearrangement in high-nuclearity osmium–platinum cluster compounds. X -Ray crystal structures of [Os 6 Pt(CO) 17 (µ 3 -NCMe)(C 8 H 12 )], [Os 6 Pt(CO) 17 (µ 4 -NCMe)(C 8 H 12 )](C 8 H 12 = cyclo-octa-1,5-diene), and [Os 6 (CO) 19 (µ 3 -NCMe)]: compounds with novel metal–acetonitrile bonding modes

The reaction of [Os6(CO)17(NCMe)] with [Pt(C8H12)2](C8H12= cyclo-octa-1,5-diene) results in the formation of [Os6Pt(CO)17(µ3-NCMe)(C8H12)](1). The geometry of (1) may be derived from that of [Os6(CO)18] by breaking one Os–Os edge and adding a terminal Pt(C8H12) fragment to one of the Os atoms constituting the central tetrahedron. Upon standing in CH2Cl2, cluster (1) isomerizes to a different geometry, [Os6Pt(CO)17(µ4-NCMe)(C8H12)](2). The …