Abstract
Mannich reaction of ketones using 1, 3-dioxolane instead of formaldehyde, paraformaldehyde, or 1, 3, 5-trioxane afforded the corresponding Mannich bases in high yields. Under the same conditions the aminomethylation of aromatics did not proceed but the intramolecular aminomethylation, like a Pictet-Spengler type reaction, proceeded smoothly.