Divergent synthesis of δ-valerolactones and furanones palladium or copper-catalyzed α-hydroxycyclopropanol ring opening cyclizations.

Cyclopropanols are versatile starting materials which can undergo various ring opening reactions due to their intrisic ring strain. Herein, we report two transition metal-catalyzed α-hydroxycyclopropanol ring opening cyclizations to divergently transform the same α-hydroxycyclopropanol substrate into two different products of enhanced value. One is a palladium-catalyzed α-hydroxycyclopropanol ring opening carbonylative lactonization to synthesize δ-valerolactones.

Tunable and recyclable polyesters from CO and butadiene.

Carbon dioxide is inexpensive and abundant, and its prevalence as waste makes it attractive as a sustainable chemical feedstock. Although there are examples of copolymerizations of CO with high-energy monomers, the direct copolymerization of CO with olefins has not been reported. Here an alternative route to functionalizable, recyclable polyesters derived from CO, butadiene and hydrogen via an intermediary lactone, 3-ethyl-6-vinyltetrahydro-2H-pyran-2-one, is described.