3-(2-aryl-2-oxoethylidene)-3,4-dihydroquinoxalin-2(1H)-ones with hydrazine hydrate (and phenylhydrazine), in boiling acetic acid undergo new acid-catalyzed rearrangement with the contraction of pyrazine ring of the quinoxaline system to form 2-(pyrazol-3-yl)benzimidazoles. Possible mechanisms of this rearrangement are considered.
摘要3-Aryl-1'H-spiro[2-pyrazoline-5,2'-quinoxalin]-3'(4'H)-ones, 可通过 3-(2-aryl-2-oxoethylidene)- 3,4-二氢
喹喔啉-2(1H)-酮与
水合
肼(和苯
肼)在沸腾的
乙酸中经历新的酸催化重排,
喹喔啉系统的
吡嗪环收缩形成2-(
吡唑-3-基)
苯并咪唑。考虑了这种重排的可能机制。