B. V. Subba Reddy, R. Anji Babu, M. Ramana Reddy, B. Jagan Mohan Reddy and B. Sridhar
RSC Adv., 2014,4, 44629-44633
DOI:
10.1039/C4RA08208G,
Paper
An intramolecular C–O insertion of 2-(2-arylamidophenyl)-2-diazoacetate has been achieved using a catalytic amount of copper triflate under mild conditions to produce 2-aryl-4H-benzo[d][1,3]oxazine-4-carboxylate in good yields. In addition, 2-diazo-2-(2-arylthioamidophenyl)acetate affords the corresponding 2-aryl-4H-benzo[d][1,3]thiazine derivatives under similar conditions. This is the first example of the synthesis of benzoxazines and benzothiazines from ortho-amidophenyl diazoacetate and ortho-thioamidophenyl diazoacetate, respectively.