# Three-component reactions of conjugated dienes, CH acids and formaldehyde under diffusion mixing conditions

## TL;DR

A new method uses diffusion mixing to create reactive intermediates that efficiently form Diels–Alder products from three components.

## Contribution

A novel three-component reaction using diffusion mixing and formaldehyde without strong acids or bases is introduced.

## Key findings

- Crotonic condensation adducts were formed at room temperature using a volatile reagent.
- The adducts reacted with dienes to produce Diels–Alder main products efficiently.
- The method avoids the need for strong acids or bases in the reaction.

## Abstract

A diffusion mixing technique with a volatile reagent was successfully used to generate crotonic condensation adducts of active methylene compounds and formaldehyde at room temperature in the absence of strong acids and bases. The formed adducts were highly reactive intermediates capable of reacting with dienes in a three-component reaction, leading to the formation of Diels–Alder main reaction products.