Cyclotrimerization of Isocyanates Promoted by one Praseodymium Benzenethiolate Complex [Pr(SPh)3(THF)3]He-Ming Wang, Hong-Xi Li, Xiang-Yang Yu, Zhi-Gang Ren, Jian-Ping Lang* Tetrahedron, 2011, 67, 1530-1535
The cyclotrimerization of aryl isocyanates and the cyclodimerization of alkyl isocyanates initiated by one praseodymium benzenethiolate complex [Pr(SPh)3(THF)3] were investigated. Comparative runs with [Pr(SPh)3(THF)3] and its precursor Pr[(Me3Si)2N]3 showed that the former has the advantages of a higher selectivity toward isocyanates, easy preparation, low catalyst loading, high conversion as well as mild reaction conditions.
