Autocatalytic Carbonyl Arylation through In Situ Release of Aryl Nucleophiles from N‐Aryl‐N′‐Silyldiazenes. Issue 30 (10th March 2020)

• Record Type: Journal Article
• Authors: Chauvier, Clément; Finck, Lucie; Irran, Elisabeth; Oestreich, Martin
• Is Part Of: Angewandte Chemie international edition. Volume 59:Issue 30(2020)
• Page Start: 12337
• Page End: 12341
• Publication Date: 2020-03-10
• Subjects: autocatalysis -- chemoselectivity -- Lewis bases -- nucleophilic addition -- silicon; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201916004
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: A method for the catalytic generation of functionalized aryl alkali metals is reported. These highly reactive intermediates are liberated from silyl‐protected aryl‐substituted diazenes by the action of Lewis basic alkali metal silanolates, resulting in desilylation and loss of N2 . Catalytic quantities of these Lewis bases initiate the transfer of the aryl nucleophile from the diazene to carbonyl and carboxyl compounds with superb functional‐group tolerance. The aryl alkali metal can be decorated with electrophilic substituents such as methoxycarbonyl or cyano as well as halogen groups. The synthesis of a previously unknown cyclophane‐like [4]arene macrocycle from a 1, 3‐bisdiazene combined with a 1, 4‐dialdehyde underlines the potential of the approach. Abstract : Under cover of nitrogen : Silyl‐protected aryl‐substituted diazenes act as masked aryl nucleophiles. Upon initiation with Me3 SiOM (M=Li, Na, and K), aryl transfer to carbonyl and carboxyl groups occurs at ambient temperature. This mild nucleophile generation is compatible with electron‐withdrawing and electron‐donating functional groups.