(-)-Mandelic acid → (S)-mandelic acid

Temperature

35 °C

To a 100 mL flask equipped with a magnetic stirrer containing a solution of a 7:3 (enantiomer A: enantiomer B) mixture of the enantiomers (3.24 g, 11 mmol) in methanol (30 mL) at 35° C. was added (R)-(−)-mandelic acid (1.09 g, 7.2 mmol) dissolved in methanol (35 mL). The resulting mixture was stirred at an internal temperature of 35° C. for 24 h. The crystallized solid was filtered through a sintered glass funnel, washed with methanol at room temperature (3×16 mL) and dried under vacuum to afford 3.08 g (63%) of the title compound (enantiomer A and (R)-(−)-mandelic acid, HPLC 97% ee) as a white solid.

1. customTo a 100 mL flask equipped with a magnetic stirrer
2. additioncontaining a solution of a 7:3 (enantiomer A: enantiomer B)
3. filtrationThe crystallized solid was filtered through a sintered glass funnel
4. washwashed with methanol at room temperature (3×16 mL)
5. customdried under vacuum

ORD record

ord-3849ec44e5704c40914e0d3f3792e514

Source dataset

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09221812B2