Tri-o-tolylphosphine → (E)-tert-butyl 6-(3-oxo-3-(pyrrolidin-1-yl) prop-1-en-1-yl)-3,4-dihydroisoquinoline-2(1H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

DIPEA (1.44 ml, 8.36 mmol) was added to a solution of 125a (650 mg, 2.09 mmol), 125b (287 mg, 2.29 mmol), Pd-(OAc)2 (46 mg, 0.21 mmol) and P(o-tol)3 (127 mg, 0.42 mmol) in propionitrile/DMF (8 ml/2 ml) and the reaction mixture was purged with nitrogen for 10 minutes, then was heated at 110° C. for 16 h. The progress of the reaction was monitored by TLC. After 16 h of stirring, the mixture was cooled to 20-35° C. and filtered on celite. The filtrate was concentrated and resultant residue diluted with water (30 ml) and extracted with ethyl acetate (2×30 ml). The combined organic layers were washed with brine (30 ml), followed by drying over anhydrous Na2SO4 and filtering. The filtrate was rotary evaporated to get residue which was purified by column chromatography using a mixture of 50% ethyl acetate/pet ether as an eluent to get the desired compound as an off-white solid (400 mg, 54%). 1H NMR (400 MHz, DMSO-d6) δ 7.50 (d, J=6.8 Hz, 2H), 7.41 (d, J=15.7 Hz, 1H), 7.20 (d, J=8.3 Hz, 1H), 6.94 (d, J=15.7 Hz, 1H), 4.56-4.46 (m, 2H), 3.63 (t, J=6.6 Hz, is 2H), 3.55 (t, J=5.9 Hz, 2H), 3.41-3.34 (m, 2H), 2.79 (t, J=5.9 Hz, 2H), 1.96-1.88 (m, 2H); 1.87-1.76 (m, 2H), 1.43 (s, 9H).

Provenance & Evidence