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A BINOL-derived chiral bifunctional sulfide catalyst bearing a phenylurea moiety was applied to enantioselective bromoaminocyclization reactions of 2-allylaniline derivatives, which provide optically active 2-substituted indoline products as important motifs for biologically active compounds. A protecting group on the nitrogen of the 2-allylaniline substrate was carefully optimized, and highly enantioselective reactions were achieved by employing thep-biphenylsulfonyl-protected substrates. The origin of the good level of enantioselectivity for the present bromoaminocyclization was also investigated on the basis of DFT calculations. The resultant optically active 2-(bromomethyl)indoline products could be transformed to various 2-substituted indolines with no loss of the optical purity., Organic & biomolecular chemistry, 18(17), pp.3367-3373; 2020

An efficient enantioselective synthesis of 3,3-disubstituted phthalides possessing a chiral quaternary carbon center was achieved via catalytic asymmetric bromolactonization that utilized BINOL-derived bifunctional sulfide catalysts. Transformations of the bromo group in optically active phthalide products were also performed to demonstrate the utility of this novel synthetic protocol., Organic and Biomolecular Chemistry, 17(15), pp.3747-3751; 2019