(R)-(tetrahydrofuran-2-yl)methyl 4-methylbenzenesulfonate → 4'-fluoro-7'-methyl-1'-[(2R)-tetrahydrofuran-2-ylmethyl]-5,6-dihydrospiro[benzo[1,2-b:5,4-b']difuran-3,3'-indol]-2'(1H)-one

Participants

Reaction Steps

Following the procedure as described in EXAMPLE 8 and making non-critical variations using 4′-fluoro-7′-methyl-5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-2′(1′H)-one to replace spiro[furo[2,3-f][1,3]benzodioxole-7,3′-indol]-2′(1′H)-one, and (R)-(tetrahydrofuran-2-yl)methyl 4-methylbenzenesulfonate to replace (R)-(1,4-dioxan-2-yl)methyl 4-methylbenzenesulfonate, 4′-fluoro-7′-methyl-1′-[(2R)-tetrahydrofuran-2-ylmethyl]-5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-2′(1H)-one was obtained (76%) as a colorless solid: mp 175-176° C. (diethyl ether); 1H NMR (300 MHz, CD3OD) δ7.14-7.06 (m, 1H), 6.71-6.52 (m, 2H), 6.25 (d, J=2.3 Hz, 1H), 4.80-4.78 (m, 2H), 4.51 (t, J=8.6 Hz, 2H), 4.26-3.69 (m, 5H), 3.00 (t, J=8.6 Hz, 2H), 2.56 (s, 3H), 2.16-1.87 (m, 3H), 1.78-1.69 (m, 1H); MS (ES+) m/z 396.0 (M+1).

Provenance & Evidence