Benzoic Acid → Methyl Benzoate

Participants

Reaction Steps

In a 1.5 l double-walled glass reactor 531 g of aqueous 30% KOH solution are submitted and are heated, respectively, to 40° C., 55° C. and 70° C. By controlled dropwise addition of 405.8 g of 26.4% N-methyl-N-nitroso-p-toluenesulfonamide (MNTSA) solution in DMSO into this KOH solution, diazomethane (DAM) is generated and is aspirated in gaseous form into a glass reactor via a frit by means of vacuum at 500 mbar. The metered addition is effected in such a way that the diazomethane concentration in the gas phase does not exceed a partial pressure of 120 mbar. With a view to determining the DAM quantity and yield, this glass reactor is charged with an acid, for example with a solution of benzoic acid in DMF, so that the DAM aspirated via the frit reacts to completion immediately to form methyl benzoate, and the content thereof is determined analytically and can be utilized as an equivalent for DAM. The following table reproduces the results:

Provenance & Evidence