摘要 |
A process for preparing felbamate and a key intermediate, 2-phenyl-1, 3-propanediol (PPD) is disclosed. PPD can be prepared by contacting (i) the enolate salt of formyl phenyl acid ester (VIII), (ii) an E-enol (X), a Z-enol (XII) or formylphenylacetic acid ester (XIV), (iii) a tropate (XIII), (iv) a tropate borate (XV) or mixtures thereof, with an acid and a borohydride reducing agent in an amount effective to give PPD. In another embodiment, PPD can also be prepared by cleaving, optionally in the presence of an acid, (v) a borate ester (XVI), (vi) a boric acid ester (XVII) or mixtures thereof. Felbamate can be prepared from wet or dry PPD by reaction with either (a) a cyanate and a strong acid in a non-halogenated solvent; or (b) chlorosulfonyl isocyanate in a suitable solvent.
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