反应详情

A solution of ethylmagnesium iodide (2.5 mmol) in dry diethyl ether (2 ml) [prepared at 20° C. from magnesium (60 mg; 2.5 mmol) and ethyl iodide (0.2 ml; 2.5 mmol)] was cooled to 0° C., copper(I) iodide (47 mg; 0.25 mmol) was added, and the mixture was stirred for 5 min. A solution of the 15-methyl-Δ15 -17-ketone (3) (148 mg; 0.5 mmol) in dry tetrahydrofuran (2 ml) was added. The reaction mixture was stirred at 20° C. for 15 min. Saturated aqueous ammonium chloride and aqueous ammonia were added, and the residue upon work-up (ethyl acetate) (150 mg; 92%) was crystallized from diisopropyl ether to give 15β-ethyl-3-methoxy-15α-methylestra-1,3,5(10)-trien-17-one (5) (135 mg), m.p. 104°-107° C. (from diisopropyl ether-methanol) [α]D +90° (c 1.0); υmax 1724 cm-1 ; δH 0.94 (3H, t, J 7.6 Hz, 15β-CH2CH3), 1.09 (3H, s, 13β-Me), 1.22 (3H, s, 15α-Me), 1.63 and 1.76 (each 1H, degen. dq., J 15.2 and 3×7.6, 15β-CH2CH3), 1.87 and 2.80 (each 1H, d, J 19.3 Hz, 16α- and 16β-H), 2.91 (2H, m, 6-H2), 3.78 (3H, s, 3-OMe), 6.64 (1H, d, J 2.8 Hz, 4-H), 6.71 (1H, dd, J 8.7 and 2.8 Hz, 2-H), and 7.21 (1H, d, J 8.7 Hz, 1-H); δC 9.0 (C-152), 18.3 (C-18), 25.9 (C-151), 27.4 (C-11), 28.6 (C-7), 29.8 (C-6), 30.3 (C-12), 34.4 (15α-Me), 37.3 (C-8), 39.4 (C-15), 45.1 (C-9), 48.9 (C-16), 49.8 (C-13), 55.2 (3-OMe), 59.8 (C-14), 111.6 (C-2), 113.6 (C-4), 126.4 (C-1), 132.3 (C-10), 137.4 (C-5), 157.6 (C-3), and 220.3 (C-17) (Found: C, 80.9; H, 9.6%; M+, 326. C22H30O2 requires C, 80.9; H, 9.3%; M, 326).

1. stirringThe reaction mixture was stirred at 20° C. for 15 min
2. customthe residue upon work-up (ethyl acetate) (150 mg; 92%) was crystallized from diisopropyl ether