Copper catalyzed CN bond formation/C–H activation: synthesis of aryl 4H-3,1-benzoxazin-4-ones
摘要:
We have developed a practical and efficient synthesis of 2-phenyl-4H-benzo[d][1,3]oxazine-4-one derivatives through copper catalyzed tandem reaction of 2-iodobenzoic acid with arylmethanamines under aerobic conditions. Compared to the literature methods toward the synthesis of 2-phenyl-4H-benzo[d][1,3]oxazine-4-one, the synthetic method reported in this Letter has broad substrate scope, mild reaction condition, and uses an inexpensive catalyst. (C) 2014 Elsevier Ltd. All rights reserved.
cyclisation of 2-aminobenzoic acids and arylaldehyde using I2 as a catalyst and an environmentally benign oxidant oxone. This method displays facile access to a diverse range of substituted aryl 4H-3,1-benzoxazin-4-ones. This synthetic methodology has many advantages such as: (1) easy availability of starting material, (2) transition metal-free condition (3) use of an environmentally benign oxidant.