Triphenylphosphine → Ethyl (+/-)-10,11-dihydro-3-[2-[2-(ethylamino)thiazol-4-yl]-1-ethoxy]-5 H-dibenzo[a,d]cycloheptene-10-acetate

Participants

Reaction Steps

A solution of 2-(ethylamino)-4-thiazoleethanol (0.33 g, 1.9 mmole) and diethyl azodicarboxylate (0.30 mL, 1.9 mmole) in anhydrous DMF (5 mL) was added dropwise over 5 min to a solution of ethyl (±)-10,11-dihydro-3-hydroxy-5H-dibenzo[a,d]cycloheptene-10-acetate (296.4 mg, 1 mmole) and triphenylphosphine (525 mg, 2 mmole) in anhydrous DMF (5 mL) at RT. The reaction was kept cool in a RT water bath during the addition. After 16 hr, the reaction was concentrated and the residue was reconcentrated from xylenes (2×). Silica gel chromatography (20% EtOAc/hexanes) gave the title compound (145.0 mg, 32%) as a yellow oil: TLC (1:1 EtOAc/hexanes) Rf0.60; 1H NMR (250 MHz, CDCl3) δ7.00-7.30 (m, 4 H), 6.98 (d, J=8.2 Hz, 1 H), 6.77 (d, J=2.6 Hz, 1 H), 6.68 (dd, J=8.2, 2.6 Hz, 1 H), 6.21 (s, 1 H), 5.00-5.25 (m, 1 H), 4.04-4.38 (m, 5 H), 3.81 (d, J=15.1 Hz, 1 H), 3.70-3.90 (m, 1 H), 3.13-3.40 (m, 3 H), 2.99 (t, J=6.7 Hz, 2H), 2.92(dd, J=14.9, 9.3 Hz, 1 H), 2.64 (dd, J=15.6, 5.0 Hz, 1 H), 2.51 (dd, J=15.6, 9.3 Hz, 1 H), 1.27 (t, J=7.2 Hz, 3 H); MS (ES) m/e 451 (M+H)+.

Provenance & Evidence