Реакция #59644

Уравнение реакции

sodium borohydride

acetate

[1-((S)-2-Benzyloxycarbonylamino-propyl)-7-bromo-1H-indazol-6-yloxy]-acetic acid ethyl ester

sodium borohydride

calcium chloride

→

solid

Выход 82.0%

{(S)-2-[7-Bromo-6-(2-hydroxy-ethoxy)-indazol-1-yl]-1-methyl-ethyl}-carbamic acid benzyl ester

Выход 82.0%

Растворители

tetrahydrofuran

ethanol

Условия реакции

Обработка

1. 1
   workup.STIRRINGThe suspension was stirred at ambient temperature for 1 h
2. 2
   ДругоеThe volatiles were evaporated
3. 3
   workup.ADDITIONthe residue mixed with water
4. 4
   Экстракцияextracted with ethyl acetate (3×50 mL)
5. 5
   СушкаThe combined extracts were dried over magnesium sulfate
6. 6
   Фильтрацияfiltered
7. 7
   Другоеevaporated to dryness

Методика

To a solution of the acetate from Step B (0.90 g, 1.84 mmol) in a mixture of tetrahydrofuran (20 mL) and ethanol (20 mL) was added sodium borohydride (70 mg, 1.84 mmol) and calcium chloride (0.21 g, 1.84 mmol) with stirring. The suspension was stirred at ambient temperature for 1 h and more sodium borohydride (70 mg, 1.84 mmol) was added. The reaction was monitored by TLC until no starting material remained. The volatiles were evaporated and the residue mixed with water and extracted with ethyl acetate (3×50 mL). The combined extracts were dried over magnesium sulfate, filtered and evaporated to dryness. Chromatography on silica eluting with a gradient of 20% to 50% EtOAc/hexane gave a solid (0.67 g, 82%): mp 97-99° C.; LCMS (+APCI) 448, 450 (M+H).

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