Expected Product H-NMR
1H-NMR (400 MHz, CDCl3) δ 5.76 (br s, 0.33 H), 5.72 (br s, 0.66 H), 4.98 (d, J = 6.1 Hz, 0.33 H), 4.77 (d, J = 4.3 Hz, 1.33 H), 3.98 − 3.85 (m, 2 H), 3.83 − 3.72 (m, 1.65 H), 3.70 − 3.64 (m, 0.66 H), 3.63 − 3.57 (m, 1.65 H), 3.05 − 2.96 (m, 1 H), 2.81 − 2.74 (m, 0.66 H), 2.67− 2.59 (m, 0.33 H), 1.45 (s, 9 H)