1'-(diphenylmethyl)-2-methylspiro[furo[2,3-f][1,3]benzoxazole-7,3'-indol]-2'(1'H)-one → 2-methylspiro[furo[2,3-f][1,3]benzoxazole-7,3'-indol]-2'(1'H)-one

Participants

Reaction Steps

Following the procedure as described in EXAMPLE 3 and making non-critical variations using 1′-(diphenylmethyl)-2-methylspiro[furo[2,3-f][1,3]benzoxazole-7,3′-indol]-2′(1′H)-one to replace 1′-(diphenylmethyl)-6-methoxy-5-methylspiro[1-benzofuran-3,3′-indol]-2′(1′H)-one, 2-methylspiro[furo[2,3-f][1,3]benzoxazole-7,3′-indol]-2′(1′H)-one was obtained (62%) as a colorless solid: mp 242-244° C. (diethyl ether); 1H NMR (300 MHz, CDCl3) δ8.20 (br s, 1H), 7.36 (d, J=8.7 Hz, 1H), 7.30-7.24 (m, 1H), 7.08 (d, J=7.5 Hz, 1H), 7.00 (d, J=8.7 Hz, 1H), 6.99-6.93 (m, 1H), 6.96 (d, J=7.8 Hz, 1H), 5.96 (d, J=6.0 Hz, 1H), 5.42 (d, J=5.0 Hz, 1H), 2.41 (s, 3H); 13C NMR (75 MHz, CDCl3) δ176.2, 165.2, 151.4, 146.1, 142.0, 138.2, 130.6, 130.1, 125.0, 123.1, 114.3, 111.5, 110.9, 88.4, 76.3, 14.6; MS (ES+) m/z 331.1 (M+39).

Provenance & Evidence