On April 30, 1980, Kaneko, Chikara; Fujii, Harue; Kawai, Shinji; Yamamoto, Atsushi; Hashiba, Kazuhiko; Kimata, Toshihiko; Hayashi, Reiko; Somei, Masanori published an article.Application In Synthesis of Methyl 2-methyl-1H-indole-3-carboxylate The title of the article was Studies on the N-oxides of π-deficient N-heteroaromatics. XXXIV. Studies on oxazepine derivatives. X. A novel synthesis of substituted indoles by photochemical ring contraction of 3,1-benzoxazepines. And the article contained the following:
A novel photochem. ring-contraction reaction of 3,1-benzoxazepines I (R = cyano, Ph; R1 = Cl, CO2H; R2 = H) yields 3-formylindoles II (R3 = CHO, R4 = H, Cl) in an aprotic solvent. This ring contraction was successfully extended to oxazepines having an alkoxycarbonyl function at the 5-position to give the indoles having this function at the 3-position. Though most of the oxazepines underwent the ring-contraction reaction only on irradiation at 254 nm, 5-carboxy derivatives or their esters afforded the ring-contraction products even at ≥300 nm. The intermediacy of 3H-indole species in these photochem. ring-contraction reactions was demonstrated by the isolation of II (R = Ph, R3 = Ac, R4 = 5-CO2Me) during the photolysis of I (R = Ph, R1 = COOMe, R2 = Me) this 3H-indole afforded II (R = Ph, R3 = Ac, R4 = 4-, and 6-CO2Me) upon further irradiation The mechanism of this acetyl migration is discussed based on the result of the photochem. acetyl migration of Me 1-acetyl-2-phenylindole-3-carboxylate. The oxazepines were obtained by photochem. rearrangement of quinoline oxides at ≥300 nm. The experimental process involved the reaction of Methyl 2-methyl-1H-indole-3-carboxylate(cas: 65417-22-3).Application In Synthesis of Methyl 2-methyl-1H-indole-3-carboxylate
The Article related to benzoxazepine ring contraction photochem, indole preparation photochem, Heterocyclic Compounds (More Than One Hetero Atom): Other 7-Membered Rings and other aspects.Application In Synthesis of Methyl 2-methyl-1H-indole-3-carboxylate
Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles