130130-98-2Relevant academic research and scientific papers
PHOTOLYTIC RING-EXPANSIONS OF 4-AZIDOQUINOLINES AND 6-AZIDODIAZINES: SOME UNEXPECTED AZEPINE RING-OPENING REACTIONS
Hayes, Roy,Schofield, Joseph M.,Smalley, Robert K.,Scopes, David I. C.
, p. 2089 - 2096 (2007/10/02)
Photolysis of 6-azidoquinazoline in MeOH-KOMe-dioxan yields 8,9-dihydro-5,7-dimethoxy-5H-pyrimidoazepine (5) which on acid hydrolysis ring-opens to the pyrimidine-carbaldehyde (7).The mechanism of formation of this unexpected dimethoxypyrimido-azepine is discussed and related to previous similar results involving 6-azido-2,3-dihydrofuro- and 6-azido-2,3-dihydrothienoquinolines. In contrast, 6-azidoquinoxaline and 6-azido-2-chloro-4-methylquinoline on photolysis under similar conditions undergo ring expansion to the expected pyrazino- and pyridoazepines (22a) and (17) respectively.However, photolysis of the latter azide in MeOH-dioxan yields the 3-(2-pyridyl)propenonitrile derivative (18) in a reaction analogous to that undergone by 6-azidophenazine.
