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In this communication, the development of a highly enantioselective stereoablative protocol for the chemoselective aryloxylation of 3-bromooxindoles with aryl alcohols have been realized. Promoted by easily available cinchona alkaloid derivatives (C6′−OH) under air- and moisture-tolerant conditions, aryloxylation of a wide range of 3-bromooxindoles bearing a 3′-alkyl substituent proceeded in high yields and excellent enantioselectivities (up to 95% ee). The newly developed strategy expediently provided the 3-phenoxy analogue of the core of alkaloid CPC-1. [ABSTRACT FROM AUTHOR]

A highlyregio- and diastereoselective TMSOTf promoted vinylogousMannich reaction for the synthesis of chiral quaternary 3-aminooxindolebutenolides from 2-silyloxy furans and chiral ketimines is described.The method is found to be very efficient and also provides a facileaccess to sterically challenging 3-aminooxindole butenolidesbearing two quaternary centers in continuation. Further, the versatilityof the method is demonstrated by the 1,4-addition of nucleophileson the sterically congested butenolide substructure. [ABSTRACT FROM AUTHOR]