Synthesis and Double-Silylation Reactions of a P2PtSi2 Complex Containing an o-Carboranylene

The reaction of the 1,2-bis(dimethylsilyl)carborane 1 with Pt(CH 2 CH 2 )(PPh 3 ) 2 yielded the cyclic bis(silyl)platinum complex 2, which was found to be a good precursor for the double-silylation reaction. Thus, the reaction of 2 with RC⋮CR‘ in refluxing toluene yielded the six-membered disilyl ring compounds B 10 H 10 C 2 (SiMe 2 ) 2 (RC CR‘) (R = Ph, R‘ = Ph ( 3 ); R = Ph, R‘ = H ( 4 ); R = Et, R‘ = Et ( 5 ); R = Me, R‘ = Me ( 6 ); R = CO 2 Me, R‘ = CO 2 Me ( 7 )). In contrast, the reaction of 1 with 1-hexyne under the same reaction conditions yielded the five-membered disilyl ring compound B 10 H 10 C 2 (SiMe 2 ) 2 (C C(C 4 H 9 )H) ( 8 ). Thermolysis of 2 with trans -cinnamaldehyde afforded the insertion compound 9, formed through the di-insertion of two carbonyl ligands into the C−Si bond of 2 . The structure of the nine-membered-ring compound 9 was determined by single-crystal X-ray crystallography. The reaction of 2 with fumaronitrile yielded the cyclization product 14, which contains two types of disilyl moieties, an imino and an N, N -bis(silyl)amino group.