Allyltributylstannane → 5-allyl-2-benzofuran-1(3H)-one

Participants

Reaction Conditions

Reaction Steps

A 4-neck, 22-L, round bottom flask equipped with a mechanical stirrer, thermocouple, nitrogen bubbler, and condenser was charged with 5-bromophthalide (650 g, 3.0 mol), allyltri-n-butyltin (1200 g, 3.6 mol), palladium tetrakis triphenylphosphine (100 g, 0.089 mol), lithium chloride (250 g, 5.9 mol) and toluene (8.8 L). The mixture was evacuated and flushed with nitrogen 3 times and then was stirred at 100° C. for 4 hours. After slowly cooling to ambient temperature, the mixture was filtered and concentrated. The resulting solid was purified by silica gel column chromatography (heptane:ethyl acetate, 0→40%) to provide 5-allyl-2-benzofuran-1(3H)-one. 1H NMR (500 MHz, CD3OD) δ 7.83 (d, J=8.0 Hz, 1H), 7.38 (d, J=8.0 Hz, 1H), 7.33 (s, 1H), 5.98 (m, 1H), 5.29 (s, 2H), 5.11-5.18 (m, 2H), 3.52 (d, J=8.2 Hz, 2H); LC/MS: [(M+1)]+=175.1; tR=2.9 min.

Provenance & Evidence