57958-49-3Relevant academic research and scientific papers
A novel intramolecular photocyclization of N-(2-bromoalkanoyl) derivatives of 2-acylanilines via 1,8-hydrogen abstraction
Nishio, Takehiko,Koyama, Hiroyuki,Sasaki, Daigo,Sakamoto, Masami
, p. 996 - 1003 (2007/10/03)
The photochemical reactions of different N-(2-acylphenyl)-2-bromo-2- methylpropanamides have been investigated. Irradiation of the N-unsubstituted anilides 1a-1c gave the corresponding dehydrobromination, cyclization, and bromo-migration products 2, 3, and 4, respectively (Table 1). Irradiation of the N-alkyl anilides 1e-1g afforded the corresponding deacylation and cyclization products 5 and 6, respectively, whereas irradiation of the N-alkyl anilides 1i-1k, carrying 2-benzoyl groups on the aromatic rings, afforded the unexpected tricyclic lactams 7 (besides 2, 5, and 6). The formation of the cyclization products 6 could be rationalized in terms of an electrocyclic ring closure of the 6π-electron-conjugated enamides 2 produced by dehydrobromination of 1, followed by thermal 1,5-acyl migration (Path B in the Scheme). The formation of the bridged lactams 7 probably follows a mechanism involving the 1,7-diradical 8 generated by ζ-H-abstraction (1.8-H transfer) by an excited acyl O-atom (Path A).
Photocyclisation of Enamides. Part 14. Substituent Effects in the Photocyclisation of N-α,β-Unsaturated Acylanilides.
Ninomiya, Ichiya,Kiguchi, Toshiko,Yamauchi, Sadami,Naito, Takeaki
, p. 197 - 202 (2007/10/02)
Irradiation of N-α,β-unsaturated acylanilides having various substituents on the benzene ring yielded a mixture of cis- and trans-octahydrophenanthridones (3a-f) and dihydroquinolones (5a, e, and f).The N-alkylanilides (
