Use of a (β‐Amidoallyl)boronate as a Nucleophilic Reagent in Catalytic Enantioselective Addition to Isatins. Issue 9 (8th March 2017)

• Record Type: Journal Article
• Authors: Sengoku, Tetsuya; Sugiyama, Akihiro; Kamiya, Yuta; Maegawa, Ryunosuke; Takahashi, Masaki; Yoda, Hidemi
• Is Part Of: European journal of organic chemistry. Issue 9(2017)
• Page Start: 1285
• Page End: 1288
• Publication Date: 2017-03-08
• Subjects: Allylation -- Amides -- Boron -- Heterocycles -- Spiro compounds; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201601612
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract : Spirocycles are attractive synthetic targets for many synthetic chemists owing to their potent and promising biological activities. We previously reported a method for the highly enantioselective allylation of various isatins with β‐amido‐functionalized allylstannanes under the influence of indium‐based chiral catalysts and applied this method to the synthesis of 2‐oxindole derivatives spiro‐fused to an α‐methylene‐γ‐butyrolactone framework. In this communication, we report the successful development of a new catalytic system that enables enantioselective tin‐free "amide allylation" with the aid of a newly prepared (β‐amidoallyl)boronate for nucleophilic addition to isatins. This system consisting of a catalytic amount of diethylzinc as a competitive candidate in the presence of chiral 1, 3‐amino alcohols incorporating an acidic phenol functionality offers new opportunities for environmentally benign access to medicinally relevant spirocyclic 2‐oxindoles. Abstract : A new catalytic system that enables the enantioselective tin‐free "amide allylation" of isatins is developed with the aid of a newly prepared (β‐amidoallyl)boronate. This system consisting of a catalytic amount of diethylzinc in the presence of chiral aminophenols offers new opportunities for environmentally benign access to medicinally relevant spirocyclic 2‐oxindoles.