反应详情

Following the procedure as described in EXAMPLE 9 and making non-critical variations using ethyl bromoacetate to replace 2-(bromomethyl)-5-(trifluoromethyl)furan, and 2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-2′(1′H)-one to replace 3-methylspiro[furo[3,2-f][1,2]benzisoxazole-5,3′-indol]-2′(1′H)-one, ethyl (2′-oxo-2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-1′(2′H)-yl)acetate was obtained (90%): mp 58-59° C. (ethyl acetate/hexanes); 1H NMR (300 MHz, CDCl3) δ 7.29-7.23 (m, 1H), 7.18-7.15 (m, 1H), 7.08-7.02 (m, 1H), 6.77-6.74 (m, 1H), 6.47 (s, 1H), 6.34 (s, 1H), 4.89-4.39 (m, 4H), 4.25-4.15 (m, 4H), 4.11-4.08 (m, 2H), 1.26 (t, J=9.0 Hz, 3H); MS (ES+) m/z 381.8 (M+1).