(3AR,5R)-5-((benzyloxy)methyl)-3a,4,5,7-tetrahydro-3H-pyrano[3,4-c]isoxazole → 2-{[(1R,3E)-1-cyclopropylpent-3-en-1-yl]oxy}-N-hydroxyethanimine

Participants

Reaction Steps

[(1R,3E)-1-(2,2-Diethoxyethoxyl)pent-3-en-1-yl]cyclopropane (C25) was converted to the product using the method described for synthesis of 2-{[(2R)-1-(benzyloxy)pent-4-en-2-yl]oxy}-N-hydroxyethanimine (C3) in the section “Alternate conversion of C2 to C4.” In this case, purification was carried out using silica gel chromatography (Gradient: 0% to 80% ethyl acetate in heptane) to provide the product as a colorless oil. By 1H NMR, this was assigned as a roughly 1:1 mixture of oxime isomers. Yield: 200 mg, 1.09 mmol, 48%. 1H NMR (400 MHz, CDCl3), characteristic peaks: δ [7.50 (dd, J=5.8, 5.6 Hz) and 6.93 (dd, J=3.6, 3.6 Hz), total 1H], 7.46 and 7.21 (2 br s, total 1H), 5.45-5.63 (m, 2H), {[4.50 (dd, half of ABX pattern, J=16.3, 3.6 Hz) and 4.40 (dd, half of ABX pattern, J=16.3, 3.7 Hz)] and [4.25 (dd, half of ABX pattern, J=12.8, 5.6 Hz) and 4.15 (dd, half of ABX pattern, J=12.9, 5.8 Hz)], total 2H}, 2.59-2.68 (m, 1H), 1.66-1.72 (m, 3H), 0.45-0.54 (m, 1H), 0.29-0.43 (m, 1H), 0.18-0.24 and 0.06-0.14 (2 m, total 1H).

Provenance & Evidence