A new strategy for the construction of optically active 5'-CF3 spiro[pyrrolidin-3,2'-oxindole] was described. A series of unprecedented 1,3-dipoles were obtained by condensation of CF3CH2NH2 with isatins. The 1,3-dipolar cycloaddition reactions of these ketimines with enals gave the products bearing four contiguous stereogenic centers in excellent yields, diastereoselectivities and enantioselectivities.

A Cinchona alkaloid-derived squaramidecatalyzed asymmetric cycloaddition of trfluoromethyl-containing azomethine ylides with b-nitroalkenes was realized under mild conditions.Aserieso fb iologically important 5'-trifluoromethyl-spiro[pyrrolidin-3,2'-oxindoles] was synthesizede fficiently by this process in excellent yields,e nantioseletivities and diastereoselectivities.

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A catalytic asymmetric method for the synthesis of 2-CF3 chromanes has been described. Generally, the squaramide-catalyzed cascade reaction of 2-hydroxychalcones with β-CF3-nitroalkenes gave the CF3-containing heterocyclic compounds bearing three contiguous stereogenic centers in excellent yields, diastereoselectivities, and enantioselectivities.