Trifluoroacetic acid water → HCID 135423412, compound

Participants

Reaction Steps

Following a general procedure,22 a solution of 4 (43 mg, 0.05 mmol) in CH2Cl2 (5 mL) was treated with TFA/water (0.5 mL, 1:1) to give a biphasic solution. After stirring at room temperature for 2.5 h, CH2Cl2 was added. The organic layer was washed (saturated aqueous NaHCO3 and brine), dried (Na2SO4), concentrated, and chromatographed (silica, CH2Cl2/hexanes) to give a purple solid (34.8 mg, 92%): IR (neat) 1674, 1557, 1110 cm−1; 1H NMR δ−1.90 (s, 2H), 1.61 (s, 18H), 1.84 (s, 6H), 2.61 (s, 3H), 7.26 (s, 2H), 7.75-7.78 (m, 4H), 8.08-8.11 (m, 4H), 8.59 (d, J=4.4 Hz, 2H), 8.69 (d, J=4.4 Hz, 2H), 9.01 (d, J=5.2 Hz, 2H), 10.03 (br s, 2H), 12.50 (s, 1H); 13C NMR δ195.1, 151.2, 139.2, 138.7, 138.3, 137.7, 134.2, 128.0, 124.4, 124.0, 122.6, 107.7, 35.2, 31.9, 29.9, 21.8, 21.7; LD-MS obsd 721.86; FAB-MS obsd 721.3931, calcd 720.3828 (C50H48N4O); λabs 428, 528, 567, 600, 657 nm.

Provenance & Evidence