Aerobic oxidation of primary alcohols catalyzed by copper complexes of 1,10-phenanthroline-derived ligands

作者：Das Oindrila; Paine Tapan Kanti^*

来源：Dalton Transactions, 2012, 41(37): 11476-11481.

DOI：10.1039/c2dt31134h

Five copper complexes [(L-1)(2)Cu(H2O)](ClO4)(2) (1), [(L-1)Cu(H2O)(3)](ClO4)(2) (1a), [(L-3)(2)Cu(H2O)](ClO4)(2) (2), [(L-5)(2)Cu(H2O)](ClO4)(2) (3) and [(L-6)(2)Cu](ClO4) (4) (where L-1 = 1,10-phenanthroline, L-3 = 1,10-phenanthroline-5,6-dione, L-5 = 1,10-phenanthrolinefuroxan and L-6 = 2,9-dimethyl-1,10-phenanthrolinefuroxan), and in situ prepared copper complexes of 2,9-dimethyl-1,10-phenanthroline (L-2) or 2,9-dimethyl-1,10-phenanthrolinedione (L-4) were used for aerial oxidation of primary alcohols to the corresponding aldehydes under ambient conditions. The copper catalysts have been found to catalyze a series of primary alcohols including one secondary alcohol with moderate turnover numbers and selectivity towards primary alcohols. Copper(II) complexes 1 (or 1a) and 2 were found to be the better catalysts among all other systems explored in this study. A copper(II)-superoxo species is implicated to initiate the oxidation reaction. Structural and electronic factors of 1,10-phenanthroline-based ligands affecting the catalytic results for aerial oxidation of alcohols are discussed.

• 出版日期2012