A new efficient strategy to access benzylic carbamates through C–H activation is reported. The use of a catalytic amount of a Cu(I)/diimine ligand in combination with NFSI ((PhSO2)2NF) or F-TEDA-PF6 as oxidants and H2NCO2R as an amine source directly leads to the C–N bond formation at the benzylic position. The mild reaction conditions and the broad substrate scope make this transformation a useful
Studies on the Bisoxazoline- and (−)-Sparteine-Mediated Enantioselective Addition of Organolithium Reagents to Imines
作者:Scott E. Denmark、Noriyuki Nakajima、Cory M. Stiff、Olivier J.-C. Nicaise、Michael Kranz
DOI:10.1002/adsc.200800017
日期:2008.5.5
The enantioselective addition of organolithiumreagents to N-anisyl aldimines promoted by chiral bisoxazolines and (-)-sparteine as external ligands is described. This reaction proceeds readily with a wide range of aldimine substrates (aliphatic, aromatic, olefinic) and organolithium nucleophiles (Me, n-Bu, Ph, vinyl) in excellent yields (81-99%) and with high enantioselectivities (up to 95.5:4.5 er)