Studies of seven-membered heterocycles. XXXII. Synthesis of N-unsubstituted 1H-1,4-benzodiazepines stabilized by intramolecular hydrogen bonding.
作者:Haruki SASHIDA、Mamoru KANAME、Takashi TSUCHIYA
DOI:10.1248/cpb.38.2919
日期:——
The stable N-unsubstituted 1H-1, 4-benzodiazepines (12a-l) having a carbonyl group or its analogue at the 2- or 9-position were prepared from the 4-azidoquinolines (13a-l) by photoreaction in the presence of sodium methoxide.It is known that N-unsubstituetd 1H-1, 4-benzodiazepines having no carbonyl group are too unstable to be isolated.Based on the spectral data, the benzodiazepines (12) isolated are assumed to be stabilized by intramolecular hydrogen bonding between the 1-NH hydrogen and the 2- or 9-carbonyl oxygen, thus allowing their isolation.
稳定的N-未取代的1H-1,4-苯二氮平(12a-l),在2位或9位具有羰基或其类似物,是通过在甲氧化钠存在下,从4-叠氮喹啉(13a-l)通过光反应制备的。已知没有羰基的N-未取代的1H-1,4-苯二氮平过于不稳定,无法分离。根据光谱数据,分离得到的苯二氮平(12)被认为是通过1-NH氢与2位或9位羰基氧之间的分子内氢键稳定,从而使其得以分离。