2-(Bromomethyl)tetrahydro-2H-pyran → tert-butyl 4-[(5,6-difluoro-2'-oxospiro[1-benzofuran-3,3-indol]-1'(2'H)-yl)methyl]piperidine-1-carboxylate

Participants

Reaction Steps

Following the procedure as described in EXAMPLE 4 and making non-critical variations using tert-butyl 4-(tosyloxymethyl)piperidine-1-carboxylate to replace 2-(bromomethyl)tetrahydro-2H-pyran, and 5,6-difluorospiro[1-benzofuran-3,3′-indol]-2′(1′H)-one to replace 5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3-indol]-2″(1H)-one, tert-butyl 4-[(5,6-difluoro-2′-oxospiro[1-benzofuran-3,3-indol]-1′(2′H)-yl)methyl]piperidine-1-carboxylate was obtained (57%) as a colorless solid: 1H NMR (300 MHz, CDCl3) δ 7.34 (ddd, J=9.0, 7.6, 1.5 Hz, 1H), 7.16-7.06 (m, 2H), 6.92 (d, J=7.8 Hz, 1H), 6.78 (dd, J=10.3, 6.3 Hz, 1H), 6.49 (dd, J=10.3, 6.3 Hz, 1H), 4.95 (d, J=9.0 Hz, 1H), 4.70 (d, J=9.0 Hz, 1H), 4.13 (br s, 2H), 3.74-3.56 (m, 2H), 2.69 (t, J=12.4 Hz, 2H), 2.07-1.96 (m, 1H), 1.68-1.63 (m, 2H), 1.45 (s, 9H), 1.32-1.26 (m, 2H); MS (ES+) m/z 493.3 (M+23).

Provenance & Evidence