| 摘要 |
<p>PURPOSE:To produce the subject unsaturated monomer of high purity by reacting a carboxylic anhydride with an active hydrogen compound such as a thiol in the presence of N,N-dicyclohexylcarbodiimide as a dehydration agent at <= a certain temperature. CONSTITUTION:A carboxylic acid of formula I (R<1> and R<2> are H, alkyl or halogen; X is O, S or NH) is reacted with an active hydrogen compound of formula II (X is O, S or NH2; R<3> is residual group obtained by removal of OH, SH or amino group from active hydrogen compound containing OH, SH or amino group; n is positive integer) in the presence of N,N- dicyclohexylcarbodiimide as a dehydration agent at <=15 deg.C to obtain the objective unsaturated monomer (e.g. tetraethylene glycol dimethacrylate) of formula III.</p> |
