Catalyst-free aqueous multicomponent domino reactions from formaldehyde and 1,3-dicarbonyl derivatives

Here we report a catalyst-free aqueous multicomponent domino reaction (MCR) capable of affording a wide range of valuable dihydropyran derivatives from simple, cheap and readily available reactants such as formaldehyde, 1,3-dicarbonyl derivatives, styrene, indole and aniline derivatives. Within the framework of green chemistry, these MCRs gather many advantages such as (i) utilization of water as a solvent, (ii) creation of up to six bonds in one sequence, (iii) 100% of carbon economy and (iv) water as a sole waste. These MCRs exhibit a broad substrate scope and open access to valuable chemicals traditionally produced through multistep processes involving catalysts or organic solvents. More generally, this work opens a new way for creating molecular complexity with maximum simplicity.