固体光气法合成氯代苯基单异氰酸酯

Synthesis of Chlorophenyl Isocyanates with Triphosgene

以固体光气和邻、间、对氯代苯胺为原料,合成邻、间、对氯苯基单异氰酸酯。考察了溶剂、原料配比和反应时间对反应的影响。确定了以1,2-二氯乙烷为反应溶剂时,合成邻氯苯基单异氰酸酯、间氯苯基单异氰酸酯、对氯苯基单异氰酸酯的最佳反应时间和氯苯胺与固体光气的摩尔比分别为5 h,2.2∶1;4.5 h,2∶1和4.5 h,2∶1;在上述反应条件下,邻、间、对氯苯基单异氰酸酯的收率分别达到84.7%、86.2%和89.0%,纯度分别为96.18%、97.83%和99.55%。

A new method to synthesize chlorophenyl isocyanates from corredponding chloroanilines and triphosgene was studied. The optimal reaction conditions were found via investigating the effects of solvent, reaction time and mole ratio of reactants on the yield. The results show that the optimal sovent is 1,2-dichlo- roethane, the optimal reaction time to prepare o-chlorophenyl isocyanates, m-chlorophenyl isocyanates and p-chlorophenyl isocyanates is respectively 5 h, 4. 5 h and 4.5 h, the optimal mole ratio of corredponding chloroanilines and triphosgene is respectively 2. 2：1, 2：1 and 2： 1. Under those conditions, the highest yields of o-chlorophenyl isocyanates m-chlorophenyl isocyanates and p-chlorophenyl isocyanates are respectively 84. 7%, 86. 2% and 89.0%, and the purities of the products are respectively 96. 18%, 97.83% and 99.55%.