CARBOAMINATION REACTIONS USING TITANIUM PRE-CATALYSTS: A CATALYTIC PROSPECT TO PREPARING CONJUGATED C–N/C–C FRAMEWORKS

Abstract

We report in this account the synthesis of a series of titanium catalysts for the carboamination of internal aryl alkynes with aldimines to produce highly arylrated α,β-unsaturated imines. Early work on the Cp₂Zr(NAr) compounds have laid the premise to develop more sophisticated, but reactive, titanium reagents supported by the popular β-diketiminates. This work has ultimately led to the preparation of simple titanium catalysts stemming from the protonation of commercially available compounds such Ti(NMe₂)₄. The latter reaction offers superior carboamination catalytic activity to the earlier Zr and Ti systems and provides an interesting approach to study how C–N and C–C bonds are formed.

ACKNOWLEDGMENTS

The author thanks Indiana University-Bloomington, the National Science Foundation (CHE-0348941), the Dreyfus Foundation, the A. P. Sloan Foundation, and the Chemical Sciences, Geosciences and Biosciences Division, Office of Basic Energy Science, Office of Science, US Department of Energy (DE-FG02-07ER15893) for support of this research. Dr. Falguni Basuli and Dr. Aneetha Halikhedkar are also acknowledged for conducting some of the synthesis and catalysis described in this account.