反应详情

(R)-2-(1H-indol-5-yl)-4,5-dihydrothiazole-4-carboxylic acid 63a was synthesized using the same method as used for 42a from 1H-indole-5-carbonitrile and used without further purification. To a vigorously stirring solution of 63a (1 mmol) and tetrabutylammonium hydrogen sulfate (0.15 mmol) in toluene (10 mL) at 0° C. was added 50% aqueous sodium hydroxide (10 mL) and sulfonyl chloride (2 mmol). The resultant solution was stirred at RT for 6 h. Then 1 N HCl was added to acidify the mixture to pH=2 and extracted with CH2Cl2, the organic layer was separated and dried (MgSO4); then evaporated to dryness to yield 64a, which were used in subsequent steps without further purification.

1. customused without further purification
2. extractionextracted with CH2Cl2
3. customthe organic layer was separated
4. dry with materialdried (MgSO4)
5. customthen evaporated to dryness