| 摘要 |
<p>1. Process for the preparation of 1-bromoalkyl carbonates of formula see diagramm : EP0252815,P8,F4 in which R**1 represents a straight-chain or branched C1 -C20 aliphatic or C5 -C15 alicyclic radical, and R**2 represents a C1 -C12 aliphatic, C5 -C20 alicyclic or C6 -C14 aromatic radical, the radical R**2 being able to carry one or more substituents chosen from the group comprising aryl, aryloxy and alkoxy radicals and chlorine, fluorine and bromine atoms, characterized in that an alpha-chlorinated carbonate of formula see diagramm : EP0252815,P9,F1 in which R**1 and R**2 have the above meanings is reacted with an anhydrous compound of formula ZBr in which Z represents a hydrogen atom, the group see diagramm : EP0252815,P9,F2 and, when R**2 is other than the aromatic radical, Z also represents a bromine atom, in the presence of a catalyst chosen from amongst heteroaromatic amines, quaternary ammonium or phosphonium halides, hexasubstituted guanidinium halides, alkali metal halides in combination with a complexing agent for their cation or alkaline earth metal halides, in a quantity of between 0.5 and 10 mole % relative to the alpha-chlorinated carbonate and at a temperature of between 40 degrees and 150 degrees C.</p> |
