The synthesis of amino-acids

AN important method of synthesising aromatic ac-amino-acids is that of Wheeler and Hoffman [1911] which involves in its first stage the condensation of the appropriate aldehyde with hydantoin, the reaction being carried out in hot glacial acetic acid containing anhydrous sodium acetate. The yield of the con- densation product so obtained varies considerably according to the aldehyde used. For example benzalhydantoin may be prepared in a yield of 80 % of the theoretical whilst indolalhydantoin is only obtainable in a yield of 47 %.