Abstract
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.
ACKNOWLEDGMENT
Financial support of this work from the Research Council of Mazandaran University is gratefully acknowledged.
Notes
a All reactions were carried out in THF at 0–10 °C, and the molar ratio of amine/formaldehyde/reductant was 2:1:4.
b All products were characterized spectroscopically (1H NMR, IR) and showed physical and spectral data in accordance with their expected structure by comparison with authentic samples.
c Yields refer to pure isolated products.