Triisopropyl borate mediated N-sulfinyl imine formation

Triisopropyl borate effects the condensation of aldehydes with sulfinamides to give N-sulfinyl imines. The reaction is amenable to 1 degrees, 2 degrees, and 3 degrees alkyl aldehydes, as well as aryl, heteroaryl, and alpha,beta-unsaturated aldehydes. In addition to tert-butanesulfinanide, the condensation is also effective with 4-toluenesulfinamide and 2,4,6-triisopropylphenylsulfinamide. This protocol proceeds under homogeneous reaction conditions and requires no post-reaction filtration of insoluble reagents or byproducts. (C) 2016 Elsevier Ltd. All rights reserved.