Isocyanide insertion and cyclization reactions to form indolines using pincer-type complexes of scandium.

The addition of 2,6-dimethylphenyl isocyanide (CN[DMeP], two equivalents) to previously reported (PNP)Sc(III) pyridyl complexes resulted in the formation of novel indoline complexes of scandium. By varying the nature of the pyridyl moiety one can intercept an intermediate prior to methyl migration. In addition to structural studies of two indolene complexes, we also propose a mechanism for the insertion and indolene ring closure.