反应详情

A mixture of 6,8-difluoro-3,4-dihydro-1H-naphthalen-2-one (521 mg, 2.86 mmol), 2-amino-pentanoic acid [5-(2-benzyloxy-1,1-dimethyl-ethyl)-[1,3,4]thiadiazol-2-yl]-amide HCl (1140 mg, 2.86 mmol) in methylene chloride (25 mL) was treated with triethyl amine (0.4 mL), then acetic acid (0.7 mL) and sodium sulfate. After stirring for 15 min, 95% pure sodium triacetoxy borohydride (767 mg, 3.4 mmol) was added and the resulting mixture was stirred at rt overnight. The mixture was quenched with dilute water, acidified to pH 3, extracted twice with methylene chloride. The orgainic layer was washed with dilute sodium hydroxide to pH 7, separated, dried and concentrated to give a dark brown oil. The oil was purified by silica gel column chromatography using 1% methanol in methylene chloride as eluent to give 2-(6,8-difluoro-1,2,3,4-tetrahydro-naphthalen-2-ylamino)-pentanoic acid [5-(2-benzyloxy-1,1-dimethyl-ethyl)-[1,3,4]thiadiazol-2-yl]-amide (578 mg) as a brown oil, LC-MS, RT=2.6 min, M+1=529.1. The corresponding HCl salt was prepared as a light pink solid after triturating with hexane.

1. stirringthe resulting mixture was stirred at rt overnight
2. customThe mixture was quenched with dilute water
3. extractionextracted twice with methylene chloride
4. washThe orgainic layer was washed with dilute sodium hydroxide to pH 7
5. customseparated
6. customdried
7. concentrationconcentrated
8. customto give a dark brown oil
9. customThe oil was purified by silica gel column chromatography