Levofloxacin 1, a potent antibacterial agent on the market that exhibits potent activity against Gram-positive and Gram-negative bacteria,1 and 2possesses a methyl group at the C-3 position with an (S)-configuration of the oxazine ring. Although various synthetic methods to (S)-(−)-7,8 -difluoro-2,3-dihydro-3-methyl-4H-1,4-benzoxazine 2, which is one of the key intermediates for 1, by resolution,[2]asymmetric hydrolysis with enzyme,[3]asymmetric reduction utilizing a ...