Iridium-Catalyzed Enantioselective and Chemodivergent Allenylic Alkylation of Vinyl Azides for the Synthesis of α-Allenylic Amides and Ketones**

Chakrabarty, A and Mukherjee, S (2022) Iridium-Catalyzed Enantioselective and Chemodivergent Allenylic Alkylation of Vinyl Azides for the Synthesis of α-Allenylic Amides and Ketones**. In: Angewandte Chemie - International Edition .

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Abstract

The first enantioselective synthesis of α-allenylic amides and ketones through allenylic alkylation of vinyl azides is reported. In these chemodivergent reactions, cooperatively catalyzed by a IrI/(phosphoramidite,olefin) complex and Sc(OTf)3, vinyl azides act as the surrogate for both amide enolates and ketone enolates. The desiccant (molecular sieves) plays a crucial role in controlling the chemodivergency of this enantioconvergent and regioselective reaction: Under otherwise identical reaction conditions, the presence of the desiccant led to α-allenylic amides, while its absence resulted in α-allenylic ketones. Utilizing racemic allenylic alcohols as the alkylating agent, the overall process represents a dynamic kinetic asymmetric transformation (DyKAT), where both the products are formed with the same absolute configuration. To the best of our knowledge, this is the first example of the use of vinyl azide as the ketone enolate surrogate in an enantioselective transformation. © 2022 Wiley-VCH GmbH

Item Type:	Journal Article
Publication:	Angewandte Chemie - International Edition
Publisher:	John Wiley and Sons Inc
Additional Information:	The copyright for this article belongs to John Wiley and Sons Inc
Keywords:	Alkylation; Catalysis; Driers (materials); Enantioselectivity; Iridium; Ketones; Molecular sieves; Olefins, Alkylating agents; Amide enolates; Enantioselective; Enantioselective synthesis; Ketone enolates; Olefin complexes; Phosphoramidites; Reaction conditions; Reaction under; Regioselective reactions, Amides
Department/Centre:	Division of Chemical Sciences > Organic Chemistry
Date Deposited:	17 Feb 2022 06:40
Last Modified:	17 Feb 2022 06:40
URI:	http://eprints.iisc.ac.in/id/eprint/71336

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