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

HRID 1518012Notes

Reaction equation

HRID 1518012 reaction equation
[S:1]1[C:6]2[CH:7]=[CH:8][C:9]([CH2:11][OH:12])=[CH:10][C:5]=2[NH:4][CH2:3][CH2:2]1.COC(C1C=CC2SCC(=O)NC=2C=1)=O.[H-].[H-].[H-].[H-].[Li+].[Al+3].[OH-].[Na+]>CCOCC.O>[S:1]1[C:6]2[CH:7]=[CH:8][C:9]([CH:11]=[O:12])=[CH:10][C:5]=2[NH:4][CH2:3][CH2:2]1

Participants

7

Reactant 4

HCID 14798Sodium HydroxideHCID 699501Methyl 3-oxo-3,4-dihydro-2H-1,4-benzothiazine-6-carboxylateHCID 21226445Aluminium lithium hydrideHCID 595606163,4-dihydro-2H-1,4-benzothiazin-6-ylmethanol

Product 1

HCID 218736933,4-dihydro-2H-1,4-benzothiazine-6-carbaldehydeYield 58%

Reagents, catalysts & solvents 2

HCID 962WaterSolvent2×HCID 3283Diethyl EtherSolvent

Procedure

(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).

Workup

  1. temperatureThe reaction mixture was cooled to 0° C.
  2. filtrationThe resulting suspension was filtered
  3. concentrationThe filtrate was concentrated

Sources & evidence

ORD record
ord-ed3c92a5e5a04618bff7088454adf633
Source dataset
uspto-grants-2012_07
Patent number
US08232391B2

Reaction notes

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