1384754-93-1Relevant articles and documents
C-Cl bond activation of ortho-chlorinated benzamides by nickel and cobalt compounds supported with phosphine ligands
Li, Junye,Wang, Chenggen,Li, Xiaoyan,Sun, Hongjian
, p. 8715 - 8722 (2012/09/08)
The C-Cl bonds of ortho-chlorinated benzamides Cl-ortho-C6H 4C(O)NHR (R = Me (1), nBu (2), Ph (3), (4-Me)Ph (4) and (4-Cl)Ph (5)) were successfully activated by tetrakis(trimethylphosphine)nickel(0) and tetrakis(trimethylphosphine)cobalt(0). The four-coordinate nickel(ii) chloride complexes trans-[(C6H4C(O)NHR)Ni(PMe3) 2Cl] (R = Me (6), nBu (7), Ph (8) and (4-Me)Ph (9)) as C-Cl bond activation products were obtained without coordination of the amide groups. In the case of 2, the ionic penta-coordinate cobalt(ii) chloride [(C 6H4C(O)NHnBu)Co(PMe3)3]Cl (10) with the [Cphenyl, Oamide]-chelate coordination as the C-Cl bond activation product was isolated. Under similar reaction conditions, for the benzamides 3-5, hexa-coordinate bis-chelate cobalt(iii) complexes (C 6H4C(O)NHR)Co(Cl-ortho-C6H4C(O)NR) (PMe3)2 (11-13) were obtained via the reaction with [Co(PMe3)4]. Complexes 11-13 have both a five-membered [C,N]-coordinate chelate ring and a four-membered [N,O]-coordinate chelate ring with two trimethyphosphine ligands in the axial positions. Phosphonium salts [Me3P+-ortho-C6H4C(O)NHR]Cl - (R = Ph (14) and (4-Me)Ph (15)) were isolated by reaction of complexes 8 and 9 as a starting material under 1 bar of CO at room temperature. The crystal and molecular structures of complexes 6, 7 and 9-12 were determined by single-crystal X-ray diffraction.
