(S)-methyl-2-bromo-3-hydroxypropanoate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Diethyl ketomalonate 15 g (0.086 mol) and methyl 2-bromo-3-hydroxy-propionate (Example 5a)) were mixed and after returning to room temperature were treated with hexane (50 ml) and 18.6 g (0.134 mol) potassium carbonate. After 6 hours an additional 5.9 g of carbonate was added and the mixture stirred at 45° overnight. after returning to room temperature

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: This compound was prepared as a possible alternate precursor to the title compound of Example 5 (c). Chloral 15.1 g (0.102 mol) and 22 g of methyl 2-bromo-3-hydroxypropionate, as prepared in Example 5(a) were mixed, and after returning to room temperature the mixture was treated with hexane 50 ml and 14.1 g (0.102 mol) potassium carbonate (added in portions over 0.5 hour). After stirring for 6 hours an additional 5 g of potassium carbonate was added and the mixture allowed to stir overnight. were mixed after returning to room temperature was added

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Methyl glyoxylate 11.3 g (0.128 mol) and methyl 2-bromo-3-hydroxypropionate 31 g (0.129 mol) were mixed and the mildly exothermic reaction allowed to cool. The mixture was then treated with hexane (50 ml) and 17.8 g (0.129 mol) potassium carbonate. Evolution of CO2 was sluggish; the mixture was warmed to 45° and allowed to stir overnight. The work-up as described in Example 1 yielded after ether removal, 13.0 g of a light yellow liquid. Distillation in vacuo gave 5.2 g (21%) of the title compound bp 84°-86° at 0.3 mm Hg as a clear colorless liquid. Analysis by GlPC indicated >96% purity, and the pmr spectrum indicated a mixture of trans & cis isomers approximately 70-80% trans. the mildly exothermic reaction to cool the mixture was warmed to 45° yielded after ether removal, 13.0 g of a light yellow liquid Distillation in vacuo