Trifluoroacetic acid → HCID 14523424, compound

Participants

Reaction Steps

Methyl 3-O-benzyl-N-benzyloxycarbonyl-2,5-dideoxy-2,5-imino-α-D-lyxofuranoside (14α) (1.015 g, 2.77 mmol) was stirred in a 1:1 mixture of trifluoroacetic acid and water (20 ml). Once all the starting material had dissolved, the solvents were evaporated (without heat) and purification by flash chromatography (ethyl acetate-hexane 1:2) gave 3-O-benzyl-N-benzyloxycarbonyl-2,5-dideoxy-2,5-imino-D-lyxose (901 mg, 92%) as a clear oil, [α]20 D -24.2° (c, 1.39 in chloroform); νmax (film) 3400 (OH), 1700 (2×CO), 1425, 1360, 1195 and 700 cm-1 ; δH 2.55 (1H, bs, OH); 3.65 (1H, 2×d, H-5); 3.79 (1H, 2×dd, H-5'); 4.03, 4.31 (2H, 2×bs, H-2, H-3); 4.44, 4.55 (1H, bs and dd, H-4); 4.51-4.71 (2H, m, CH2Ph); 5.09-5.20 (2H, m, CH2 -Z); 7.29-7.40 (10H, m, H-Ph); 9.49, 4.59 (1H, 2×d, H-1, J1,2 0.7 Hz). m/z: 91 (100%), 108 (68%), 230 (50%), 356 (M+H+, 20%). (Found C, 67.76; H, 6.48; N, 3.77. C20H21NO5 requires C, 67.59; H, 5.96; N, 3.94). Methyl 3-O-benzyl-N-benzyloxycarbonyl-2,5-dideoxy-2,5-imino-β-D-lyxofuranoside (14β) (976 mg, 2.64 mmol) reacted similarly: it afforded the title compound (15) (820 mg, 87%), spectroscopically identical to that prepared above, under the same reaction conditions.

Provenance & Evidence