p-Toluenesulfonic acid → tert-Butyl N-[(10R,11E,14S)-10-methyl-9-oxo-8,16-diazatricyclo[13.3.1.02,7]nonadeca-1(19),2(7),3,5,11,15,17-heptaen-14-yl]carbamate

Participants

Reaction Conditions

Reaction Steps

To a round bottom flask was added 45E (1.34 g, 3.18 mmol), pTsOH (0.665 g, 3.50 mmol), and dichloromethane (265 ml). The clear yellow solution was degassed with argon for 30 min. The reaction was then warmed to 40° C. for 1 h. Then a solution of GrubbsII (0.486 g, 0.572 mmol) in DCM (4 mL) was added dropwise to the reaction mixture. After 4.5 h, the reaction was cooled to rt, washed with sat. NaHCO3, brine, dried over MgSO4, filtered, and concentrated to give brown solid. The residue was purified by silica gel chromatography to give the desired product (0.97 g, 78%) as light brownish foam. 1H NMR (500 MHz, METHANOL-d4) δ 8.57-8.52 (m, 1H), 7.51-7.41 (m, 3H), 7.34-7.30 (m, 1H), 7.28 (dd, J=5.2, 1.7 Hz, 1H), 6.92 (s, 1H), 5.71 (ddd, J=15.3, 10.5, 4.7 Hz, 1H), 4.61 (dd, J=11.4, 3.4 Hz, 1H), 4.39 (dd, J=15.1, 9.4 Hz, 1H), 3.14-3.07 (m, 1H), 2.72 (ddd, J=8.6, 7.2, 3.7 Hz, 1H), 2.05-1.95 (m, 1H), 1.44 (s, 9H), 1.04 (d, J=6.9 Hz, 3H). MS (ESI) m/z: 394.1 (M+H)+.

Provenance & Evidence