Alonso, Miguel E. published the artcileStudies on the origin of dihydrofurans from α-diazocarbonyl compounds. Concerted 1,3-dipolar cycloaddition vs. nonsynchronous coupling in the copper chelate catalyzed reactions of α-diazodicarbonyl compounds with electron-rich olefins, Synthetic Route of 14284-06-1, the publication is Journal of Organic Chemistry (1982), 47(19), 3747-54, database is CAplus.
The Cu chelate catalyzed thermolysis of alkyl 2-diazo-3-oxobutyrate and of 3-diazo-2,4-pentanedione in the presence of vinyl ethers, to give 4-(alkoxycarbonyl)- and 4-acyl-2,3-dihydrofurans, is used to probe the mechanism of this transformation in terms of the concerted 1,3-dipolar cycloaddition of the metal-oxocarbene complex vs. the initial formation of the cyclopropane followed by 1,3-sigmatropic rearrangement to the heterocycle. Evidence is presented in favor of a third possibility, namely, that of a nonsynchronous stereospecific addition of the metal-carbene to the olefinic substrate which accounts for the formation of cyclopropanes, dihydrofurans, and products of apparent allylic C-H insertion and cyclopropane structural isomerization from a common intermediate. This mechanism is supported by a study of the addition of Et 2-diazo-3-oxobutyrate to benzo[b]furan.
Journal of Organic Chemistry published new progress about 14284-06-1. 14284-06-1 belongs to copper-catalyst, auxiliary class Copper, name is Copper(II) ethylacetoacetate, and the molecular formula is 0, Synthetic Route of 14284-06-1.
Referemce:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4660968/,
Special Issue “Fundamentals and Applications of Copper-Based Catalysts”