1-Isogranatanin-4-ol synthesis

Yield:855829-28-6 91%

Reaction Conditions:

with sodium tetrahydroborate in methanol at -10 - 0; for 1 h;

Steps:

1

1-Aza-bicyclo[3.3.1]nonan-4-one (11.92 g, 85.6 mmol) is dissolved in 160 ml MeOH and cooled to -10⁰C. NaBH₄ (1.69 g, 42.9 mmol)) is added portionwise so that the inner temperature does not exceed 0⁰C. The reaction mixture is stirred at -10⁰C for 1h. Water is added and the solvents are evaporated. The remaining solid is dissolved in MTBE/MeOH, filtered over hyflo and the filtrate is evaporated to give 19.28 g of crude product which is purified by chromatography over aluminum oxide (40Og₁ eluent: MTBE/MeOH 95:5 to 80:20) to give 10.96 g (91%) (4SR,5RS)-1-aza-bicyclo[3.3.1]nonan-4-ol.

References:

WO2007/68476,2007,A1 Location in patent:Page/Page column 18-19