作者: Izabela Gryca , Barbara Machura , Jan Grzegorz Małecki , Joachim Kusz , Lidia S. Shul'pina
DOI: 10.1039/C5DT03598H
关键词:
摘要: The reactions of mer-[Re(p-NTol)X3(PPh3)2] (X = Cl, Br) with chelating phenolate-based ligands (2-(2-hydroxy-5-methylphenyl)benzotriazole (HL1), 2-(2-hydroxyphenyl)benzothiazole (HL2) or 2-(2-hydroxyphenyl)benzoxazole (HL3)) afforded a series p-tolylimido rhenium(V) complexes cis- trans-(X,X)-[Re(p-NTol)X2(L)(PPh3)]·yMeCN (where X Br; L L1, L2, L3 and y 0–2) [Re(p-NTol)X(L)(PPh3)2]Z·pPPh3 Z ReO4, PF6; p 0 1). reported compounds were characterized by elemental analysis, FT-IR, NMR (1H, 13C 31P) X-ray crystallography. Interestingly, the halide ions [Re(p-NTol)Cl2(L1)(PPh3)]·MeCN (1) [Re(p-NTol)Cl2(L2)(PPh3)]·2MeCN (3) are in cis relative dispositions, whereas [Re(p-NTol)Br2(L)(PPh3)] (L1 for 2, L2 4 6) [Re(p-NTol)Cl2(L3)(PPh3)] (5) found to be trans-(X,X) isomers. [Re(p-NTol)X(L)(PPh3)2](PF6) L1 L2) [Re(p-NTol)X(L3)(PPh3)2](PF6)·PPh3 have been tested oxidative catalysis. A few exhibited very good catalytic properties oxidation alcohols tert-BuOOH (TBHP) acetonitrile solution at moderate temperatures. Complex [Re(p-NTol)Cl(L2)(PPh3)2]PF6 (13) is catalyst choice 1-phenylethanol acetophenone (in 80% yield; turnover number attained 290 after 30 h) cyclooctanol cyclooctanone 88% yield). Notably lower activity has alkanes TBHP. Product distribution methylcyclohexane indicates some steric hindrance around reaction center.