Toluene → (R)-8-(2-azido-2-(4-methyl-1-oxo-1,3-dihydroisobenzofuran-5-yl)ethyl)-2-(4-methyl-5-oxo-2,5-dihydrofuran-3-yl)-2,8-diazaspiro[4.5]decan-1-one

Participants

Reaction Conditions

Reaction Steps

To a suspension of 8-[(2S)-2-hydroxy-2-(4-methyl-1-oxo-1,3-dihydro-2-benzofuran-5-yl)ethyl]-2-(4-methyl-5-oxo-2,5-dihydrofuran-3-yl)-2,8-diazaspiro[4.5]decan-1-one (Example 8, 500 mg, 1.13 mmol) and diphenylphosphoryl azide (643 mg, 1.36 mmol) in a mixed solvent of toluene and dichloromethane (v:v, 10:1, 11 mL) was added DBU (343 mg, 2.26 mmol). The reaction mixture was stirred at 35° C. for 20 h. The solvent was removed by evaporation and the residue was purified by flash column chromatography (0-100% ethyl acetate in petroleum ether) to afford the title compound. 1H NMR (400 MHz, CDCl3): δ 7.78 (d, J=8.0 Hz, 1H), 7.55 (d, J=8.0 Hz, 1H), 5.26 (s, 2H), 5.23 (s, 2H), 4.99 (dd, J=4.0 Hz, 9.2 Hz, 1H), 4.00 (t, J=6.8 Hz, 2H), 2.95-2.87 (m, 2H), 2.78-2.73 (m, 1H), 2.60-2.57 (m, 1H), 2.48-2.43 (m, 1H), 2.33 (s, 3H), 2.10 (t, J=6.8 Hz, 2H), 2.03-1.86 (m, 6H), 1.51-1.48 (m, 2H); MS-ESI (m/z): 466 (M+1)+.

Provenance & Evidence