2,6-Lutidine → [1-Cyano-5-(4-hydroxy-6-methoxy-7-methyl-3-oxo-1,3-dihydro-isobenzofuran-5-yl)-3-methyl-pent-3-enyl]-phosphonic Acid

Participants

Reaction Steps

To a solution of {1-cyano-5-[6-methoxy-7-methyl-3-oxo-4-(2-trimethylsilanyl-ethoxy)-1,3-dihydro-isobenzofuran-5-yl]-3-methyl-pent-3-enyl}-phosphonic acid diethyl ester (35 mg, 0.065 mmol) in acetonitrile (2 mL) was added TMSBr (180 μL, 1.38 mmol) and 2,6-lutidine (160 μL, 1.38 mmol). The reaction solution was allowed stir at room temperature for one hour before quenching with MeOH. The reaction mixture was dried under reduced pressure and the residue was purified by RP HPLC using a C 18 column with a gradient of H2O, 0.1% TFA-acetonitrile, 0.1% TFA to provide 15 mg (60%) of the desired product. 1H NMR (300 MHz, CD3OD) δ 1.86 (s,3H), 2.15 (s, 3H), 2.38-2.57 (m, 2H), 3.17-3.28 (m, 1H), 3.44 (d, J=7.2 Hz, 2H), 3.80 (s, 3H), 5.25 (s, 2H), 5.47 (t, J=7.2 Hz, 1H) ppm; 31P (121.4 MHz, CD3OD) δ 15.28 ppm; MS (m/z) 380 [M−H]−, 382 [M+H]+.

Provenance & Evidence