Lipoic acid → HCID 86630289, compound

Participants

Reaction Conditions

Reaction Steps

To a room temperature solution of (R)-(+)-1,2-dithiolane-3-pentanoic acid (2.66 g, 12.9 mmol) and 4-Chloromethyl-7-hydroxy-2H-chromen-2-one (1) (2.40 g, 11.4 mmol) in anhydrous benzene (160 mL) was added 1,8-diazabicyclo[5.4.0]undec-7-ene (3.8 mL, 25 mmol) in one portion. The reaction mixture was heated to 80° C. (oil bath temperature) for 1 h, cooled to room temperature, then quenched with aqueous 15% citric acid (200 mL). The resulting suspension was filtered, and the collected insoluble material was suspended in acetone (100 mL), sonicated for 60 s, then filtered onto a bed of silica gel (˜10 g). The suspension-sonication-filtration step was repeated a second time. Concentration of the filtrate under reduced pressure followed by flash column chromatography (1% MeOH in CH2Cl2) provided the desired product as a pale yellow powder (1.08 g, 25%).

Provenance & Evidence