2-Bromoethanol → 2-(7-Methoxy-1,1-dioxido-4H-1,2,4-benzothiadiazin-4-yl)ethanol

Participants

Reaction Steps

To a solution of 7-methoxy-4H-1,2,4-benzothiadiazine 1,1-dioxide (4.0 g, 18.8 mmol) in a mixture of 30 ml of DMF and 30 ml of CH3CN there are added 8.6 g (56.6 mmol) of CsF and 1.47 ml (18.8 mmol) of 2-bromoethanol. Stirring is carried out for 2 hours at 75° C. and 1.47 ml (18.8 mmol) of 2-bromoethanol are added. After 6 more hours at 75° C., a further 1.47 ml (18.8 mmol) of 2-bromoethanol and then 2.8 g (18.8 mmol) of CsF are added and stirring is continued at 75° C. overnight. The salts are filtered off at ambient temperature and rinsed with CH3CN; the filtrate is evaporated to dryness. The residue is taken up in CH2Cl2, and the organic phase is washed with saturated NaCl solution and dried (MgSO4). After evaporation, the sticky residue is taken up in a mixture of ethyl ether/CH2Cl2. The gum is triturated until a solid is obtained, which is filtered off to obtain the title compound.

Provenance & Evidence