88916-73-8Relevant academic research and scientific papers
Synthesis and reactivity of metallacyclic manganese α-(silyloxy)alkyl complexes (CO)4MnC(R)(OSi(CH3)3)P(C6H 5)2. A new thermodynamic driving force for CO insertion
Vaughn, George D.,Krein, K. Alex,Gladysz
, p. 936 - 942 (2008/10/08)
Reaction of (CO)5MnR (2) with (C6H5)2PSi(CH3)3 (3) gives metallacyclic α-(silyloxy)alkyl complexes (CO)4MnC(R)(OSi(CH3)3)P(C6H 5)2 (4) in 42-75% yields (R = CH3 (a), CH2Si(CH3)3 (b), C6H5 (c), 2-naphthyl (d)). These reactions are of interest in that the metallacyclic carbon is derived from an insertion of CO into the manganese-carbon bond of 2 - a step for which subsequent silicon-oxygen bond formation provides an additional thermodynamic driving force. Reaction of (CO)5MnCOC6H5 with 3 also gives 4c (63%). Phosphines (C6H5)3P and 3 react with 2a at nearly the same rate, both separately and in competition experiments. Passage of 4b through wet silica gel gives acyl complex cis-(CO)4Mn(COCH2Si(CH3)3)P(C 6H5)2H (6b, 84%), presumably via metallacyclic α-hydroxyalkyl complex (CO)4MnC(CH2Si(CH3)3)(OH)P(C 6H5)2 (7b). Reaction of 2b with (C6H5)2PH also gives 6b (91%). Reaction of (CO)5MnH and 3 in hexanes gives cis-(CO)4Mn(H)P(C6H5)2Si(CH 3)3 (8, 72%). Both 8 and 4a are inert to 300-360 psi of CO. The thermodynamics of these transformations are analyzed.
