Reaction Steps
Zinc powder (7.39 g, 113 mmol) was added to a solution of 54 (6.86 g, 14.1 mmol) in THF (150 mL), HOAc (150 mL), and H2O (50 mL). The mixture was stirred at reflux for 40 min, cooled, and filtered through Celite eluting with EtOAc. The filtrate was evaporated and the residue diluted with H2O and extracted with EtOAc (×2). The extracts were washed with H2O, aq NaHCO3, and dried (Na2SO4) and evaporated. Recrystallization from MeOH gave methyl 3-(t-butyloxycarbonyl)-1-hydroxymethyl-1,2-dihydro-3H-pyrrolo[3,2-e]indole-7-carboxylate (55) as a white solid (3.86 g, 79%), mp 189.5-191° C. (dec.). The mother liquor was purified by chromatography (40% EtOAc-petroleum ether) to give more alcohol (0.74 g, 15%). 1H NMR [(CD3)2SO] δ 11.88 (s, 1 H, NH), 7.87 (v br s, 1 H, H-4), 7.29 (d, J=8.9 Hz, 1 H, H-5), 7.11 (d, J=1.4 Hz, 1 H , H-8), 4.95 (t, J=5.2 Hz, 1 H, OH), 4.03 (t, J=10.5 Hz, 1 H), 3.92-3.86 (m, 1 H), 3.87 (s, 3 H, CO2Me), 3.82-3.75 (m, 1 H), 3.67 (br s, 1 H), 3.55-3.48 (m, 1 H), 1.51 (s, 9 H, t-Bu); 13C NMR δ 161.6, 151.8, 136.2, 134.6, 127.8, 123.7, 122.6, 113.3, 113.3, 111.3, 105.5, 79.3, 63.1, 51.7, 51.2, 42.2, 28.1. Anal. Calculated for C18H22N2O5 : C, 62.4; H, 6.4; N, 8.1. Found: C, 62.3; H, 6.6; N, 8.3%.