1'-(diphenylmethyl)-6-methoxy-5-methylspiro[1-benzofuran-3,3'-indol]-2'(1'H)-one → 7'-chloro-5,6-dihydrospiro[benzo[1,2-b:5,4-b']difuran-3,3'-indol]-2'(1'H)-one

Participants

Reaction Steps

Following the procedure as described in EXAMPLE 3 and making non-critical variations using 7-chloro-1-(diphenylmethyl)-3-(6-hydroxy-2,3-dihydro-1-benzofuran-5-yl)-1,3-dihydro-2H-indol-2-one to replace 1′-(diphenylmethyl)-6-methoxy-5-methylspiro[1-benzofuran-3,3′-indol]-2′(1′H)-one, 7′-chloro-5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-2′(1′H)-one was obtained (78%) as a colorless solid: mp>250° C. (diethyl ether); 1H NMR (300 MHz, DMSO-d6) δ11.01 (s, 1H), 7.30 (d, J=8.0 Hz, 1H), 7.70 (d, J=7.1 Hz, 1H), 7.00-6.94 (m, 1H), 6.56 (s, 1H), 6.40 (s, 1H), 4.80 (d, J=9.4 Hz, 1H), 4.68 (d, J=9.4 Hz, 1H), 4.49 (m, 2H), 2.95 (m, 2H); 13C NMR (75 MHz, DMSO-d6) δ178.5, 161.0, 160.5, 139.4, 134.7, 128.4, 123.4, 122.3, 120.1, 119.8, 118.9, 113.8, 92.3, 79.8, 72.0, 58.0, 28.2; MS (ES+) m/z 313.7 (M+1), 315.7 (M+1).

Provenance & Evidence