1,3-Dioxolan-4-one, 5-(2-hydroxyethyl)-2,2-dimethyl-, (5R)- synthesis

Yield:174563-88-3 10.1 g

Reaction Conditions:

Stage #1: D-Malic acid;acetonewith boron trifluoride diethyl etherate in tetrahydrofuran at 0 - 20;
Stage #2: with sodium tetrahydroborate;boron trifluoride diethyl etherate in tetrahydrofuran at 0 - 60;

Steps:

3 Preparation of 3(R)-α-hydroxy-γ-butyrolactone

10g of D-malic acid was added to 100ml of dry tetrahydrofuran, 6ml of acetone and 15g of boron trifluoride ethyl ether were added dropwise successively at 0°C, then the reaction was stirred and reacted for 1 hour, then slowly raised to room temperature, and the reaction was continued overnight. After the reaction was completed, 3.4 g of sodium borohydride was added in batches, and then the reaction solution was cooled to 0° C., and 10.0 g of boron trifluoride ether was slowly added dropwise. After the addition, the temperature was raised to 60° C. to react overnight. After the reaction was completed, it was quenched with saturated sodium bicarbonate solution, extracted with ethyl acetate, dried over anhydrous sodium sulfate and concentrated under reduced pressure to obtain 10.1 g of intermediate (R)-II as an oily liquid.

References:

CN112939901,2021,A Location in patent:Paragraph 0024; 0025