Sodium Hydroxide → 3,4-dihydro-2H-1,4-benzothiazine-6-carbaldehyde

Participants

Reaction Steps

(3,4-Dihydro-2H-benzo[1,4]thiazin-6-yl)-methanol. To a solution of 3-oxo-3,4-dihydro-2H-benzo[1,4]thiazine-6-carboxylic acid methyl ester (750 mg, 3.4 mmol) in Et2O (32 mL) was added LiAlH4 (240 mg, 6.3 mmol) and the resulting suspension was stirred at RT for 24 h. The reaction mixture was cooled to 0° C. and treated with H2O (0.5 mL), 15% aq. NaOH (0.5 mL), and H2O (1.5 mL). The resulting suspension was filtered. The filtrate was concentrated to provide 340 mg (58%) of the title compound as an amber oil. MS (ESI): exact mass calculated for C9H11NOS, 181.06; m/z found, 182.1 [M+H]+. 1H NMR (500 MHz, CDCl3): 6.96 (d, J=7.9, 1H), 6.60 (dd, J=7.9, 1.6, 1H), 6.49 (d, J=7.9, 1H), 4.52 (s, 2H), 3.65-3.62 (m, 2H), 3.06-3.04 (m, 2H).

Provenance & Evidence