Steric Control of Cyclometallation Reactions in Schiff-Base Complexes of Cobalt(I) Containing an Anchoring Diphenylphosphanyl Group
作者:Hans-Friedrich Klein、Robert Beck、Ulrich Flörke、Hans-Jürgen Haupt
DOI:10.1002/1099-0682(200212)2002:12<3305::aid-ejic3305>3.0.co;2-a
日期:2002.12
Monosubstitution occurs under 1 bar of ethene giving the π-ethene complexes [(2-Ph2PC6H4CNR-C,P)Co(C2H4)(PMe3)2] [8: R = CH(CH3)2, 9: R = cyclo-C6H11] and [2-Ph2PC6H3(CHNR)-C1,P}Co(C2H4)(PMe3)2] [10: R = C(CH3)3]. The molecular structure of 9 shows an equatorial π-ethene ligand. Iodomethane oxidizes 2 and 3 to afford the cobalt(II) complexes [(2-Ph2PC6H4CNR-C,P)CoI(PMe3)2] [11: R = CH(CH3)2, 12: R = cyclo-C6H11]
2-(二苯基膦基)烷基亚氨基苯甲醛(2-Ph2PC6H4CHNR)与[CoCH3(PMe3)4]反应形成复合物[(2-Ph2PC6H4CNR-C,P)Co(PMe3)3]中的五元金属环[1: R = C2H5, 2: R = CH(CH3)2, 3: R = cyclo-C6H11] 而在 [2-Ph2PC6H3(CHNR)-C1,P}Co(PMe3)3] 的形成过程中选择性地遵循邻位金属化途径[4:R = C(CH3)3]。X 射线分析证实了在 4 的分子结构中存在四元钴环。2 和 3 的羰基化得到单羰基衍生物 [(2-Ph2PC6H4CNR-C,P)Co(CO)(PMe3)2] [5: R = CH(CH3)2, 6: R = cyclo-C6H11] 而 4通过插入形成环膨胀 [2-Ph2PC6H3(CHNR)CO-C,P}Co(CO)(PMe3)2] [7: R = C(CH3)3]。单取代发生在