Methyl β-(2-Methyl-5-Oxocyclopentenyl-) Propionate and Ethyl 3-Methyl-6-Oxohepta-2, 4-Dienoate

As part of a broad study of γ-diketone synthesis 2 by way of cyclopropanation of enol ethers or esters with diazoacetic ester or diazomethyl ketones followed by hydrolytic cyclopropane scission it became of interest to learn whether ester carbonyl groups within interacting distance of the diazocarbonyl unit would interfere in the cyclopropanation step and whether furans can be made to undergo cyclopropanation like enol ethers. The following two investigations were undertaken to resolve these issues.