Microcapsule Enabled Multicatalyst System

Abstract

We present a new microencapsulated catalyst and report its use in a tandem multicatalyst reaction. Using an encapsulation technique, we developed an active, site-isolated amine catalyst that is capable of catalyzing the addition of nitromethane to an aldehyde. When a second Lewis acid catalyst is added, the nitroalkene intermediate is trapped and converted to the corresponding Michael adduct. We show that if the amine catalyst is not encapsulated, the two catalysts cannot function together. Moreover, if the two reactions are performed in sequence rather than in tandem, the first reaction results in an undesired dinitro product and the desired Michael adduct is not formed.