3.2.2. (Z)-1-Methyl-3-(1-phenylethylidene)indolin-2-one (**(***Z***)-5a**)

80% Yield; yellow solid; mp = 128.9–130.2 ◦C; *<sup>R</sup>*<sup>f</sup> = 0.45 (silica gel, hexane:EtOAc = 4:1); 1H NMR (500 MHz, CDCl3): *<sup>δ</sup>* 7.67 (d, *<sup>J</sup>* = 7.6 Hz, 1H), 7.46–7.36 (m, 3H), 7.35–7.27 (m, 3H), 7.10 (td, *J* = 7.7, 1.0 Hz, 1H), 6.84 (d, *J* = 7.7 Hz, 1H), 3.15 (s, 3H), 2.65 (s, 3H) ppm; 13C NMR (125 MHz, CDCl3) *δ* 166.4, 153.2, 143.4, 142.6, 128.6, 128.2, 128.1, 127.4, 124.0, 123.7, 123.6, 121.8, 107.8, 25.8, 25.6 ppm; HRMS (EI): calcd for C17H15NO [M+] : 249.1154, found 249.1151.
