A simple and general method in the synthesis of N-alkoxycarbonyl ketimines derived from isatins has been described first. Generally, the enantioselective addition of 1,3-dicarbonyl compounds to this kind of ketimine affords chiral 3-amino oxindoles in high yield and excellent ee.

The first asymmetric aza-Friedel-Crafts reaction of indoles and pyrroles with isatin-derived N-Boc ketimines catalyzed by chiral phosphoric acids is reported. In general, derivatives of substituted 3-amino-2-oxindoles were obtained with excellent enantioselectivities and high yields.

A zinc-mediated addition of methyl and terminal alkynes to chiral N-tert-butanesulfinyl ketimines for the preparation of optical quaternary 3-amino oxindoles was reported. In general, the operationally simple reaction affords the desired products in high yields and good to excellent diastereoselectivities. Subsequent convenient cleavage of sulfinyl protecting group under mild conditions was presented without racemization.

An organocatalytic enantioselective Strecker reaction for the synthesis of 3-amino-3-cyanooxindoles has been developed. Employing a quinine-derived thiourea catalyst, the nucleophilic addition of trimethylsilyl cyanide to N-Boc-ketimines affords 3-amino-3-canooxindoles in good to excellent yields (78-98%) and very good enantioselectivities (up to 94%). Furthermore, to the best of our knowl-edge, this method also represents the first enantioselective organocatalyzed Strecker reaction with N-Boc-ketimines as electrophiles.

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