Reaction Steps
Following the procedure as described in EXAMPLE 5 and making non-critical variations using (3R)-5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-2′(1′H)-one to replace 5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-2′(1′H)-one, and 2-(bromomethyl)-5-(trifluoromethyl)furan to replace 5-(chloromethyl)-2-methoxypyrimidine, (3R)-1′-{[5-(trifluoromethyl)furan-2-yl]methyl}-5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-2′(1′H)-one was obtained (83%) as a colorless solid: mp 68-70° C. (diethyl ether); 1H NMR (300 MHz, CDCl3) δ7.32-7.26 (m, 1H), 7.20 (d, J=7.4 Hz, 1H), 7.10-7.05 (m, 1H), 6.98 (d, J=7.8 Hz, 1H), 6.75-6.74 (m, 1H), 6.45 (s, 1H), 6.42 (s, 2H), 5.12 (d, J=16.2 Hz, 1H), 4.96 (d, J=9.0 Hz, 1H), 4.85 (d, J=16.2 Hz, 1H), 4.70 (d, J=9.0 Hz, 1H), 4.54 (t, J=8.6 Hz, 2H), 3.07-2.90 (m, 2H); 13C NMR (75 MHz, CDCl3) δ177.4, 161.8, 161.1, 151.9, 141.9, 141.2, 132.5, 128.8, 123.9, 123.7, 120.5, 120.0 (2C), 118.7, 112.6, 112.5, 109.2, 108.7, 93.1, 80.3, 72.3, 57.6, 36.8, 28.9; MS (ES+) m/z 427.9 (M+1).
