1H NMR (400 MHz, CDCl3) δ 7.27 – 7.22 (m, 2H), 7.22 – 7.15 (m, 1H), 7.04 (s, 1H), 6.78 (d, J = 7.4 Hz, 2H), 5.77 (s, 2H), 1.36 (s, 9H), 1.27 (s, 9H). 13C{1H} NMR (101 MHz, CDCl3) δ 198.2, 144.5, 143.1, 138.3, 128.5, 127.0, 125.4, 125.0, 49.9, 44.6, 31.4, 30.2, 27.6. HRMS (EI) m/z: calcd for C19H26N2O, 298.2045; found, 298.2040.