Cobalt POCOP Pincer Complexes via Ligand C–H Bond Activation with Co<sub>2</sub>(CO)<sub>8</sub>: Catalytic Activity for Hydrosilylation of Aldehydes in an Open vs a Closed System
作者:Yingze Li、Jeanette A. Krause、Hairong Guan
DOI:10.1021/acs.organomet.8b00273
日期:2018.7.9
A series of cobalt POCOP pincer complexes with the formulas 2,6-(iPr2PO)2-4-R′-C6H2}Co(CO)2 (R′ = H (1a), NMe2 (1b), OMe (1c), CO2Me (1d)), 2,6-(Ph2PO)2C6H3}Co(CO)2 (1e), and 2,6-(tBu2PO)2C6H3}Co(CO) (2f) have been synthesized through C–H bond activation of the corresponding pincer ligands with Co2(CO)8. These complexes have been demonstrated to catalyze the hydrosilylation of PhCHO with (EtO)3SiH
一系列具有式2,6-(i Pr 2 PO)2 -4-R'-C 6 H 2 } Co(CO)2(R'= H(1a),NMe 2(1b),OMe(1c),CO 2 Me(1d)),2,6-(Ph 2 PO)2 C 6 H 3 } Co(CO)2(1e)和2,6-(t Bu 2 PO)2 C 6 H 3 } Co(CO)(2f)是通过Co 2(CO)8相应的钳形配体的C–H键活化而合成的。这些配合物已被证明可以催化PhCHO与(EtO)3 SiH的氢化硅烷化反应,该反应具有诱导期和递减顺序,依次为1b > 1c > 1a > 1d > 1e。该催化规程可以应用于周转数高达300的各种醛。二羰基络合物中的CO配体在室温下可与13 CO交换,并在高温下与钴部分解离。CO的取代由叔丁基异氰化物在50-80°C时用1a完成,导致形成2,6-(i Pr 2 PO)2 C 6 H 3 } Co(CN