Safe and Efficient Reductive Methylation of Primary and Secondary Amines UsingN-Methylpyrrolidine Zinc Borohydride

An efficient, general procedure for reductive methylation of primary and secondary amines with 37% formaldehyde using N-methylpyrrolidine zinc borohydride (ZBHNMP) as a reducing agent gave the corresponding tertiary amines in excellent yields. The reaction was carried out in tetrahydrofuran under neutral conditions at 0–10 °C.