On the effect of microwave energy on the Michael addition of dimethyl malonate on levoglucosenone.

Among biomass-derived platform molecules one of the most prominent structures is levoglucosenone (LGO) from which it is possible to derive a wide array of solvents, chemicals, and polymeric materials. In this work we investigated the Michael addition of dimethyl malonate on levoglucosenone by testing several alternative catalysts ranging from Lewis acids to structured silicas and clays. The work had the double aim to i) optimize the reaction using the widely reported KF/Alumina catalyst, giving a frame of reference for its relative activity in this Michael addition and ii) conduct a catalyst screen while investigating various reaction mechanisms. Among the tested catalysts, Ca(OH) was the best candidate to substitute KF/Alumina, reaching yields >90 % after only 5 min of microwave irradiation.