ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 25, Number 6
JKCSEZ 25(6)
December 20, 1981 

For the urethane formation reaction of isocyanate with alcohol, orientation of approach of alcohol toward isocyanate was investigated theoretically by means of MO method. As a result of EHT and CNDO/2 calculations, it was found that the reaction proceeding via 4-centered mechanism, in which ROH is coplanar with isocyanate plane was energetically favored. It was also shown that the oxygen of ROH attacks the isocyanate carbon prior to the formation of 4-center complex. The reaction was found to be a charge controlled one.