Hydrochloric Acid → 4-(Tert-butyl)cinnamic acid

Participants

Reaction Conditions

Reaction Steps

(2E)-N-(1-Acetyl-3,3-dimethylindolin-6-yl)-3-[4-(tert-butyl)phenyl]prop-2-enamide. To a solution of 1-acetyl-3,3-dimethyl-6-nitroindoline, Example 31(c), (110 mg, 0.47 mmol) in ethyl ether (3 mL), magnetically stirred in a round-bottomed flask at 0° C., was added tin (II) chloride dihydrate (0.67 g, 2.96 mmol, Aldrich) and cond HCl (0.3 mL). The reaction mixture was stirred at 0° C. for 10 min, allowed to warm to 25° C. then stirred at that temperature overnight. The reaction mixture was washed with 10 N NaOH (10 mL), extracted with EtOAc and concentrated in vacuo. Analogous to the procedure used to prepare Example 1, the crude product and 4-tert-butyl-trans-cinnamic acid (92 mg, 0.45 mmol, EMKA-Chemie) provided, after purification by silica gel chromatography (2:3 hexane:EtOAc), the title product. MP 121° C. MS (ESI, pos. ion) m/z: 391 (M+1).

Provenance & Evidence