1'-(diphenylmethyl)-5,6-dimethylspiro[1-benzofuran-3,3'-indol]-2'(1'H)-one → 5,6-dimethylspiro[1-benzofuran-3,3'-indol]-2'(1'H)-one

Participants

Reaction Steps

Following the procedure as described in EXAMPLE 3 and making non-critical variations using 1′-(diphenylmethyl)-5,6-dimethylspiro[1-benzofuran-3,3′-indol]-2′(1′H)-one to replace 1′-(diphenylmethyl)-6-methoxy-5-methylspiro[1-benzofuran-3,3′-indol]-2′(1′H)-one, 5,6-dimethylspiro[1-benzofuran-3,3′-indol]-2′(1′H)-one was obtained (88%) as a colorless solid: mp 206-207° C. (ethyl acetate/hexanes); 1H NMR (300 MHz, DMSO-d6) δ10.5 (s, 1H), 7.23-7.18 (m, 1H), 7.03-7.01 (m, 1H), 6.94-6.88 (m, 2H), 6.73 (s, 1H), 6.43 (s, 1H), 4.68 (ABq, 2H), 2.13 (s, 3H), 1.99 (s, 3H); 13C NMR (75 MHz, DMSO-d6) δ178.9, 159.1, 142.2, 138.0, 133.3, 129.1, 127.0, 124.2, 124.1, 122.7, 111.2, 110.2, 79.5, 58.2, 20.2, 19.1; MS (ES+) m/z 266.3 (M+1).

Provenance & Evidence