1,8-Diazabicyclo(5.4.0)undec-7-ene → 3-Vinyl-tetrahydro-pyran-3-carboxylic acid benzyl ester

Participants

Reaction Steps

A solution of 3-(1-trifluoromethanesulfonyloxy-ethyl)-tetrahydro-pyran-3-carboxylic acid benzyl ester (8.368 mmol) in dichloromethane (100 mL) was treated with 1,8-diazabicyclo[5.4.0]undec-7-ene (5.0 mL, 33.472 mmol). After stirring at room temperature for 2.5 h, the volatiles were removed in vacuo and the residue was purified by silica gel chromatography using a 100 g Isolute cartridge eluted with a continuous gradient of iso-hexanes/ethyl acetate 1:0 to 4:1 to afford the title compound (809.5 mg, 39% over two steps) as a colorless oil. 1H NMR (300 MHz, CDCl3) δ 1.58-1.80 (m, 3H), 2.29-2.40 (m, 1H), 3.42-3.54 (m, 2H), 3.81 (app dt, J=10.5, 4.2 Hz, 1H), 4.27 (dd, J=11.4, 1.8 Hz, 1H), 5.13-5.27 (m, 4H), 5.77 (dd, J=17.4, 10.9 Hz, 1H), 7.31-7.42 (m, 5H).

Provenance & Evidence