| 摘要 |
2136872 9324489 PCTABS00028 Described is the preparation of 5-dichloroacetyl-3,3,6-trimethyl-9-oxo-1,5-diazabicyclo¢4,3,0!nonane (I) by reacting 3,3,6-trimethyl-9-oxo-1,5-diazabicyclo¢4,3,0!nonane (II) with dichloroacetyl chloride in the presence of a solvent and a base. The reaction is carried out in a two-phase system comprising a practically water-insoluble solvent and water, and sodium or potassium hydroxide is added as the base in proportion to the amount of dichloroacetyl chloride consumed so that the aqueous phase has a pH of 7 to 9. The solid product formed is then separated off. |
