(Chemical Equation Presented) In the presence of molybdenum oxide the dehydrative cyclization of N-acylserines, N-acylthreonines, and N-acylcysteines can be carried out under Dean-Stark conditions in toluene to give oxazolines and thiazolines. The ammonium salts (NH4)6Mo 7O24·4H2O and (NH4) 2MoO4 have excellent catalytic activities for the dehydrative cyclization of serine and threonine derivatives, and the acetylacetonate complex MoO2(acac)2 has a remarkable catalytic activity for the dehydrative cyclization of cysteine derivatives. In addition, polyaniline-supported MoO2(acac)2 can easily be recovered and reused.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry