The effect of coordination on the reaction of N-tosyl imines with diethylzinc

The effect of coordination on the reaction of N-tosyl imines and diethylzinc was studied in detail. It showed that there was strong coordination between N-tosyl imine and diethylzinc. Due to this coordination, N-tosyl imines could be reduced directly through the β-H transferring mechanism by diethylzinc in nonpolar solvents to afford the corresponding secondary amines in excellent yields at mild conditions. The coordination of diethylzinc and N-tosyl imine was hindered by reacting in polar solvents or adding TMEDA to the reaction, it afforded ethylating product partially or exclusively.