Reaction Steps
Following the procedure as described in EXAMPLE 3 and making non-critical variations using 1′-(diphenylmethyl)-4′-(4-phenoxyphenyl)-2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-2′(1′H)-one to replace 1′-(diphenylmethyl)-6-methoxy-5-methylspiro[1-benzofuran-3,3′-indol]-2′(1′H)-one, 4′-(4-phenoxyphenyl)-2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-2′(1′H)-one was obtained (74%) as an off-white solid: mp 243-246° C. (diethyl ether); 1H NMR (300 MHz, CDCl3) δ 8.63-8.53 (m, 2H), 8.07 (d, J=8.5 Hz, 1H), 7.74-7.64 (m, 2H), 7.57-7.39 (m, 2H), 7.36-7.19 (m, 3H), 7.02-6.93 (m, 2H), 6.50 (s, 1H), 5.96 (s, 1H), 5.28 (d, J=15.8 Hz, 1H), 4.98 (d, J=15.8 Hz, 1H), 4.69 (d, J=9.2 Hz, 1H), 4.34 (d, J=9.2 Hz, 1H), 4.32-4.08 (m, 4H); 13C NMR (75 MHz, CDCl3) δ 177.8, 155.4, 150.3, 149.6, 147.2, 144.8, 142.7, 138.2, 137.2, 136.3, 135.7, 131.2, 130.4, 129.7, 129.2, 128.0, 126.9, 128.0, 126.9, 125.6, 122.9, 122.7, 121.8, 111.3, 109.5, 99.6, 64.6, 64.1, 58.4, 46.3; MS (ES+) m/z 463.9 (M+1).
