Novel approach for the synthesis of N-unsubstituted 2,3,5,6-tetrahydro-4H-2,6-methano-1,3-benzoxazocine-4-thiones

An efficient one-pot method for the synthesis of 2,3,5,6-tetrahydro-4H-2,6-methano-1,3-benzoxazocine-4-thiones in high yields has been developed via regioselective tandem reaction of coumarin-3-thioamides and ketones containing different methylene groups. Further oxidation with hydrogen peroxide under basic conditions leads to the formation of N-unsubstituted derivatives of 2,3,5,6-tetrahydro-4H-2,6-methano-1,3-benzoxazocin-4-one.