Ba. Davis et Da. Durden, Reductive methylation of secondary amines containing reducible, hydrolyzable and sterically hindered groups, SYN COMMUN, 30(18), 2000, pp. 3353-3362
Aliphatic secondary amines, including those that are sterically hindered, u
ndergo reductive methylation under mild conditions in high yield using form
aldehyde and sodium phosphite solution without reducing or hydrolyzing ethy
nyl, ester or cyano groups.