Hydrogen Bromide → 2-Benzhydrylsulfanylacetic acid

Participants

Reaction Steps

U.S. Pat. No. 4,177,290 discloses an alternative process for the application on an industrial scale (scheme 2). Benzhydrol (5), thiourea (6) and 2-chloroacetic acid (7) are reacted in the presence of hydrobromic acid to obtain 2-[(diphenylmethyl)sulfenyl]acetic acid (8), which is oxidized with hydrogen peroxide to afford 2-[2-[(diphenylmethyl)sulfinyl]acetic acid (9). This is reacted with NaHCO3 and dimethyl sulfate and the resulting methyl ester (10) is converted to modafinil by treatment with ammonia.

Provenance & Evidence