Diethyl Ether → (r/s)-3-Cyclohexyl-2-hydroxy-propanoic acid, 4-(methoxy)benzyl ester

Participants

Reaction Steps

A solution of 0.50 g (2.32 mmol) of 4-(methoxy)benzylglyoxylate (azeotropically dried with 2×25 mL of toluene) in 2 mL of ether at −78° C. was treated with 7 mL of 0.5 M of cyclohexylmethylmagnesium bromide (prepared from 1.0 mL (7.1 mmol) of bromomethylcyclohexane, 174 mg (7.1 mmol) of Mg, 0.1 mL (1.1 mmol) of 1,2-dibromoethane in 14 mL of ether) and the resulting mixture was stirred cold for 1 h. The reaction was quenched with 1 N NaHCO3 and the quenched mixture was partitioned between 100 mL of ether and 100 mL of sat'd NaHCO3. The aqueous layer was separated and extracted with 100 mL of ether. The combined organic layers were dried over MgSO4 and concentrated. Flash chromatography on silica gel using 4:1 v/v hexanes/EtOAc afforded 180 mg (26%) of the title compound: RF: 0.32 (4:1 v/v hexanes/EtOAc); 1H NMR (300 MHz) δ 0.84-1.82 (m, 13H), 3.81 (s, 3H), 4.23 (m, 1H), 5.14 (s, 2H), 6.90 (d, J=8.7, 2H), 7.29 (d, J=8.7, 2H).

Provenance & Evidence