Cyclization during the dehydrohalogenation of perfluoroalkyl-substituted iodoalkylmalonates. Thermal rearrangement of the derived 2-(perfluoroalkyl)methylcyclopropane-1,1-dicarboxylates was written by Brace, Neal O.. And the article was included in Journal of Organic Chemistry in 1975.Reference of 17920-23-9 This article mentions the following:
Addnl. data considered in abstracting and indexing are available from a source cited in the original document. Perfluoroalkylmalonates, RCH2CHICH2CH(CO2Et)2 [R= (CF3)2CF, CF3(CF2)n, n= 2,3,5] cyclized with NaOH in aqueous and nonaqueous systems to give cyclopropanedicarboxylic acids and esters (I; R= same as above; R1= H, Et) in excellent yields. I [R= CF3(CF2)n, n= 2,3; R1= Et] rearranged thermally at 225-240° by a sigmatropic, 1,5-H shift to the corresponding RCH:CHCH2CH(CO2Et)2. I [R= CF3(CF2)n, n= 2,3; R1= H] decarboxylated and rearranged at 145-200° to a mixture of RCH:CHCH2CH2CO2H (II; R same as above) and cis- and trans-III (R same as above). At reduced CO2 pressure rearrangement was almost completely suppressed in favor of decarboxylation to III. Cis-III, but not trans-III slowly isomerized at a higher temperature to II. A concerted rearrangement and decarboxylation of I (R same as above; R1= H) facilitated by both opening of the strained ring and release of CO2, was suggested. In the experiment, the researchers used many compounds, for example, Diethyl 2-(prop-2-yn-1-yl)malonate (cas: 17920-23-9Reference of 17920-23-9).
Diethyl 2-(prop-2-yn-1-yl)malonate (cas: 17920-23-9) belongs to esters. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. Esterification is the general name for a chemical reaction in which two reactants (typically an alcohol and an acid) form an ester as the reaction product. Esters are common in organic chemistry and biological materials.Reference of 17920-23-9
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics