Ethanol → 1,1-Dimethylethyl 5-ethoxy-3,4-dihydro-2(1H)-isoquinolinecarboxylate

Participants

Reaction Steps

2.1 g (8.43 mmol) of 2-t-butoxycarbonyl-5-hydroxy-1,2,3,4-tetrahydroisoquinoline (Example 7), 2.77 g (10.5 mmol) triphenylphosphine and 0.75 mL (12.6 mmol) ethanol were dissolved in dry tetrahydrofuran and 1.63 mL (10.5 mmol) diethylazodicarboxylate was added dropwise. After completion of the reaction (tlc, 1% MeOH), the mixture was diluted with dichloromethane, washed with aqueous sodium bicarbonate and with aqueous sodium chloride, evaporated to dryness and purified by silicagel chromathography (System B). Yield 1.55 g, 66%. 1H NMR (CDCl3): 7.12 (1H, t, 8.1 Hz), 6.69 (2H, t, 8.1 Hz), 4.55 (2H, s), 4.02 (2H, q, 6.8 Hz), 3.63 (2H, t, 5.6 Hz), 2.76 (2H, t, 5.9 Hz), 1.48 (9H, s), 1.41 (3H, t, 7.1 Hz).

Provenance & Evidence