Filatov V, Kukushkin M, Kuznetsova J, Skvortsov D, Tafeenko V, Zyk N, Majouga A, Beloglazkina E. Synthesis of 1,3-diaryl-spiro[azetidine-2,3′-indoline]-2′,4-dionesviathe Staudinger reaction:cis- ortrans-diastereoselectivity with different addition modes.
RSC Adv 2020;
10:14122-14133. [PMID:
35498462 PMCID:
PMC9051608 DOI:
10.1039/d0ra02374d]
[Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 03/30/2020] [Indexed: 01/31/2023] Open
Abstract
A new synthetic approach for realizing biologically relevant bis-aryl spiro[azetidine-2,3′-indoline]-2′,4-diones was developed based on Staudinger ketene–imine cycloaddition through the one-pot reaction of substituted acetic acids and Schiff bases in the presence of oxalyl chloride and an organic base. A series of [azetidine-2,3′-indoline]-2′,4-diones were synthesized using this method. For comparison, the same compounds were obtained using a known technique, where ketene is generated from pre-synthesized acyl chloride. It was shown that the use of oxalyl chloride for ketene generation in the one-pot reaction at room temperature allows for the reversal of the diastereoselectivity of spiro-lactam formation, unlike previously described procedures.
Two experimental techniques of the ketene–imine Staudinger reaction allowed different diastereomers of spiro-indolinone-β-lactams to be obtained.![]()
Collapse