Imino ene-type reaction of enamines with N-sulfonylimines and application to diastereoselective synthesis of N-sulfonyl-1,3-diamines

Bi(OTf)3-Catalyzed Diastereoselective One-Pot Synthesis of 1,3-Diamines with Three Continuous Stereogenic Centers

A highly modular, diastereoselective one-pot-synthesis of 1,3-diamines with three contiguous stereogenic centers is reported. Our method provides a fast and efficient access to 1,2- anti-2,3- anti-1,3-diamines from three readily available building blocks. This Bi(OTf)₃-catalyzed reaction is insensitive to air and moisture and can be performed on a multigram scale.

Stereoselective Synthesis of Nitrogen-Containing Compounds from Enamines

The domino reaction of enamines, electrophiles (N-sulfonylimines, N-tosylisocyanate, or diethyl azodicarboxylate), and trichlorosilane provided trans-amines (trans/cis = > 99:1 to 96:4). Meanwhile, the sequential imino ene-type reaction of enamines and electrophiles/NaBH₃CN reduction afforded cis-amines (trans/cis = 1:>99 to 15:85). The reversal of selectivity is discussed on the basis of diastereofacial selection of the plausible iminium ion intermediates. For the domino reaction of cyclic enamines and cyclic imines, high enantioselectivity (er = 95.7:4.3 to 99.9:0.1) was achieved by utilizing chiral Lewis base catalysts.