| 摘要 |
<p>A process is disclosed for preparing a compound of the formula <CHEM> wherein R1 and R3 are the same or a different straight or branched chain lower alkyl group; and R2 is hydrogen, a straight or branched chain lower alkyl, benzyl, or phenyl group, or a phenyl group substituted with a halo, a straight or branched chain lower alkyl or alkoxy, an amino, a lower dialkylamino or a nitro group The process comprises adding a compound of the formula <CHEM> to an aqueous solution of an acid to form a reaction mixture, the mole ratio of the acid to formula (II) being about 1.75 to 2.5; maintaining the reaction mixture at a temperature of about 85 to 95 DEG C for about 1 to 3 hours; neutralizing the reaction mixture; recovering the precipitate effected by the neutralizing step; and separating from the precipitate the compound of formula (I). The compounds 4 (or 5)-methyl-5 (or 4)-ethyl-2-propyl-2-imidazoline-4,5-diol hydrochloride (or 4), and 4 (or 5)-methyl-2,5 (or 2,4)-di-n-propyl-2-imidazoline-4,5-diol are also disclosed.</p> |
