Ethyl (2E)-(2,3-dihydro-4H-1-benzopyran-4-ylidene)acetate → Ethyl (3,4-dihydro-2H-1-benzopyran-4-yl)acetate

Participants

Reaction Conditions

Reaction Steps

To a solution of chroman-(4E)-ylidene-acetic acid ethyl ester and chroman-(4Z)-ylidene-acetic acid ethyl ester (1.68 g, 7.47 mmol, 1 eq.) in EtOH (91 mL) under N2, palladium on activated carbon (10 wt. %, 168 mg) was added. The flask was carefully evacuated and refilled with H2 (3×). The black suspension was stirred at 45° C. under an H2-atmosphere for 18 hours. The black suspension was filtered through Celite. The Celite was rinsed with EtOH. The filtrate was concentrated in vacuo to give (±)-chroman-4-yl-acetic acid ethyl ester as a grey oil. The product was used without further purification.

Provenance & Evidence