反应详情

Following the procedure for Intermediate 5 starting from 1-methyl-5-(5-ethyl-6,8-dioxaspiro[2.5]octan-7-yl)-4-nitro-pyrazole gave 2-ethyl-7-(2-methyl-4-nitro-pyrazol-3-yl)oxepan-4-one as a colourless solid (240 mg, 13% over two steps). 1H NMR (400 MHz, CDCl3) δ 8.04 (s, 1H), 5.67 (dd, J=11.0, 2.4 Hz, 1H), 4.02 (s, 3H), 3.94 (dd, J=10.2, 5.2 Hz, 1H), 3.04 (td, J=13.3, 3.3 Hz, 1H), 2.79-2.63 (m, 3H), 2.20-2.12 (m, 1H), 2.05-1.92 (m, 1H), 1.67-1.57 (m, 2H), 0.94 (t, J=7.4 Hz, 3H).