Methanesulfonic Acid → Dimethyl (3-oxo-1,3-dihydro-2-benzofuran-1-yl)phosphonate

Participants

Reaction Conditions

Reaction Steps

Dimethyl phosphite was added drop-wise to a solution of sodium methoxide in methanol at 0° C. 2-Carboxybenzaldehyde (H) was then added portion-wise to the reaction mixture as a slurry in methanol, with the temperature kept below 5° C. The resulting pale yellow solution was warmed to 20° C. over 1 hour. Methanesulphonic acid was added to the reaction drop-wise and the resulting white suspension was evaporated in vacuo. The white residue was quenched with water and extracted into chloroform. The combined organic extracts were washed with water, dried over MgSO4, and evaporated in vacuo to yield (3-oxo-1,3-dihydro-isobenzofuran-1-yl)phosphonic acid dimethyl ester (G) as a white solid (yield: 95%). This was then used without further purification in the next stage.

Provenance & Evidence