¹³C NMR (126 MHz, CDCl₃) δ 151.30 (ddd, J = 5.6, 10.7, 250.3 Hz, 1C), 146.93 (dt, J = 4.0, 11.9 Hz, 1C), 137.36 (td, J = 15.3, 248.6 Hz, 1C), 105.32 (q, J = 8.1 Hz, 1C).