Feeding sequence-regulated divergent (4 + 1 + 1′) annulations of α-bromo carbonyls and 1-azadienes via computational calculation-based mechanism elucidation. Issue 7 (21st February 2022)

• Record Type: Journal Article
• Authors: Zeng, Rong; Wang, Zheng; Peng, Ruikun; Yan, Peng; Yang, Jie; Zhou, Qian; Gu, Jing; Zheng, Peng-Fei; Chen, Ying-Chun; Ouyang, Qin
• Is Part Of: Organic chemistry frontiers. Volume 9:Issue 7(2022)
• Page Start: 1884
• Page End: 1889
• Publication Date: 2022-02-21
• Subjects: Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1039/d2qo00052k
• Languages: English
• ISSNs: 2052-4110

Abstract

Abstract : Based on computational calculation-based mechanism elucidation, a new controllable divergent (4 + 1 + 1′) reaction was realised by changing the feeding sequence of two different α-bromo substrates in the presence of tertiary amines and bases. Abstract : By investigating the mechanism of our previously reported (4 + 1 + 1) annulations of α-bromo carbonyls and 1-azadienes via density functional theory (DFT) calculations, the formation of a carbon anion intermediate and its attack on another α-bromo carbonyl substrate in a (4 + 1 + 1) manner were proposed as more reasonable processes. On this basis, a new controllable divergent (4 + 1 + 1′) reaction was realised by changing the feeding sequence of two different α-bromo substrates in the presence of tertiary amines and bases. A series of fused benzofuro[3, 2- b ]pyridines or benzo[4, 5]thieno[3, 2- b ]pyridines with more functional diversity were efficiently constructed in moderate to excellent yields.