Appel reaction conditions have been harnessed to affect a mild biosynthetically inspired dehydration of endoperoxides to deliver multi-substituted electron rich furans. Unlike traditional dehydrative procedures, this method is metal and acid free, and can be achieved under redox neutral conditions. It is general for a range of aryl and alkyl substituted endoperoxides, and is functional group tolerant. Furthermore, this procedure has been used to deliver an effective total synthesis of the furan fatty acid (FFA) F5.

•A formal [4+2]-cycloaddition reaction of donor-acceptor cyclobutanes gives tetrahydropyrans.•The allyl group was shown to be a better donor than benzyl.•A number of highly substituted tetrahydropyrans were prepared.The allyl group was shown to be preferred over the benzyl group as a donor in the formal [4+2]-cycloaddition reaction between a donor-acceptor cyclobutane and various aldehydes to give tetrahydropyrans.Download high-res image (68KB)Download full-size image

An unexpected azeto[2,3-c]quinolizinedione has been isolated during synthetic studies on the base catalyzed condensation of ethyl 6-methylpyridin-2(1H)-on-1-ylacetate with benzil. Closure of a fused four-membered azetidinone ring occurred when potassium hexamethyldisilazide was employed as the base. The structure of the product was confirmed by synchrotron X-ray crystallography. A possible mechanism for the formation of the product is considered.

A high yielding rearrangement of epoxy-esters, under Lewis acid conditions, to give bicyclic ortho esters is reported.

A range of highly substituted tetrahydropyrans have been prepared by reaction of a donor–acceptor cyclobutane, where the donor is a metal–alkyne complex, with an aldehyde under Lewis acid conditions.

Appel reaction conditions have been harnessed to affect a mild biosynthetically inspired dehydration of endoperoxides to deliver multi-substituted electron rich furans. Unlike traditional dehydrative procedures, this method is metal and acid free, and can be achieved under redox neutral conditions. It is general for a range of aryl and alkyl substituted endoperoxides, and is functional group tolerant. Furthermore, this procedure has been used to deliver an effective total synthesis of the furan fatty acid (FFA) F5.

A high yielding rearrangement of epoxy-esters, under Lewis acid conditions, to give bicyclic ortho esters is reported.