Sodium Acetate → methyl (S)-4-bromo-3-hydroxybutyrate

An argon purged solution of the dibromide obtained in step (b) above (20.8 g, 75.4 mM) and anhydrous sodium acetate (NaOAc) (21.0 g) in ethyl acetate (370 ml) and glacial acetic acid (37 ml) was treated with 5% Pd/C (1.30 g) and the black suspension stirred under one atmosphere of H2 while monitoring uptake (22.4 l/mole). After 2.0 hours H2 uptake was complete, the mixture was filtered through Celite, the filtrate washed with saturated NaHCO3 and brine and then dried over anhydrous MgSO4 and evaporated to give the crude bromoester title product as a brown oil. The crude oil was combined with another batch (starting from 36.77 g of the dibromide) and vacuum distilled to give 25.771 g (61.3%) of the pure bromoester title product as a clear oil with b.p.=79°-80° C. (1.0 mm Hg) and with consistent C13NMR spectral data. TLC (1:1) ethyl acetatehexane, Rf=0.44, PMA.

1. filtrationthe mixture was filtered through Celite
2. washthe filtrate washed with saturated NaHCO3 and brine
3. dry with materialdried over anhydrous MgSO4
4. customevaporated

ORD 기록

ord-c1c07e0e76264453a0d5b0005fa4f701

출처 데이터셋

uspto-grants-1993_10

DOI

10.6084/m9.figshare.5104873.v1

특허 번호

US05256692