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80657-57-4 Synthesis

METHYL (S)-(+)-3-HYDROXY-2-METHYLPROPIONATE

80657-57-4
175 suppliers
$15.00/250mg

75-16-1
270 suppliers
$12.00/10ml

73295-12-2
22 suppliers
$165.00/50mg

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Yield:73295-12-2 88.4%

Reaction Conditions:

Stage #1: 3-hydroxy-(2S)-methylpropionate;methylmagnesium bromide in diethyl ether at 10 - 25;
Stage #2: with hydrogenchloride in diethyl ether;water at 10 - 25; pH=4;

Steps:

1

Reference Example 1; Preparation of IM-WR2; MO X IM-WRl IM-WR2To a stirred solution of MeMgBr (245 mL 3M solution, 3.5 eq.) in Et₂O (536 mL) cooled in an ice bad to internal temperature 10-15°C, a solution of methyl (S)-3-hydroxy-2- methyl-propionate (TM-WRl, 25 g, 1 eq.) in Et₂O (104 mL) was added drop wise for an interval of 30 min; the internal temperature was kept below 20°C. The obtained grayish suspension was let to reach room temperature (20-25⁰C) and was stirred overnight (ca. 12h). The reaction was completed (monitored by GC); the reaction mixture was cooled again in an ice bad to internal temperature 10-15°C. Next, ice (60 g) and then 5N aqueous HCl solution (150 mL) were very slowly added keeping the internal temperature bellow 25°C. To the resulting emulsion a few drops of HCl solution (ca. 1 mL) were added to adjust pH= 4. The both layers of the emulsion were separated; the aqueous phase and a half of the organic phase were put in a continuous liquid liquid extractor (apparatus for performing continuous extraction) and the product was extracted from the aqueous into the organic phase for 24h (bath temperature 50-56⁰C). The organic phases were again combined and concentrated under reduced pressure (600-700 mbar) giving the product as yellowish oil (25.39 g). The latter was purified by distillation at vacuo (0.3-0.1 mbar, 80-95⁰C). Yield of IM-WR2: 22.26 g (88.4%, GC-purity 98.5%)

References:

WO2010/9879,2010,A2 Location in patent:Page/Page column 96

80657-57-4 Synthesis

80657-57-4
175 suppliers
$15.00/250mg

676-58-4 Synthesis