Formation of substituted 2-iminooxazolidines via intermolecular 1,2-addition/intramolecular N-vinylation using 3-substituted-2-bromo-2-propen-1-ols as substrates

Cascade Nucleophilic Attack/Addition Cyclization Reactions to Synthesize Oxazolidin-2-imines via (Z)-2-Bromo-3-phenylprop-2-en-1-ols/3-phenylprop-2-yn-1-ols and Diphenyl Carbodiimides

Two concise strategies to synthesize oxazolidin-2-imines by cascade nucleophilic attack/addition cyclization reactions of (Z)-2-bromo-3-phenylprop-2-en-1-ols/3-phenylprop-2-yn-1-ols and diphenyl carbodiimides without a transition-metal catalyst have been developed. The reactions exhibited good substrate applicability tolerance, and a variety of substituted (Z)-4-((Z)-benzylidene)-N,3-diphenyloxazolidin-2-imines were synthesized in moderate to excellent yields with good stereoselectivity. The reports also provided a convenient strategy to synthesize 3-phenylprop-2-yn-1-ols by (Z)-2-bromo-3-phenylprop-2-en-1-ols. The economic and practical methods provide a great advantage for potential industrial synthesis of oxazolidin-2-imines.

Visible-light promoted three-component tandem reaction to synthesize difluoromethylated oxazolidin-2-imine

An effective synthetic method to achieve difluoromethylated oxazolidin-2-imine has been developed via visible-light promoted three-component tandem reaction of aryl allylamines, 2-BTSO2CF2H (BT = Benzothiazole) and isocyanates. This method features mild reaction conditions and good functional group tolerance, and the reaction mechanism was confirmed by experiments and interpreted by quantum chemical calculations.