83132-87-0Relevant academic research and scientific papers
PMR SPECTRA AND cis-trans ISOMERISM OF 2-METHYLENEPYRROLIDINE AND 2-METHYLENETETRAHYDROFURAN DERIVATIVES
Solov'eva, N. P.,Marchenko, N. B.,Granik, V. G.,Sheinker, Yu. N.
, p. 693 - 696 (1982)
A number of secondary enamines and cyclic enol ethers (2-methylenetetrahydrofuran derivatives) were synthesized by the reaction of O-methylbutyrolactim and 2,2-diethoxytetrahydrofuran, respectively, with compounds that have an active methylene link.The absence of reversible cis-trans isomerization was established in a study of the PMR spectra of these compounds.The configuration of the secondary enamines is determined by the possibility of the formation of a strong intramolecular hydrogen bond between the carbonyl-containing substituent and the NH group.In the case of the cyclic enol ethers it was shown that the energy barrier to cis-trans isomerization is greater than 25 kcal/mole and that, as a consequence of this, the geometrical isomers can be separated preparatively.
Synthesis of furo[3,2-c]pyridine and furo[2,3-d]pyrimidine derivatives from butyrolactone diethylacetal
Marchenko,Granik
, p. 58 - 61 (2007/10/02)
The reaction of butyrolactone acetal with CH acids was used to synthesize 2-methylenetetrahydrofuran derivatives. The latter react with dimethylformimide acetal to give a dieneamine that is capable of undergoing cyclization to furo [3,2-c]pyrimidine derivatives. This two-ring system was also synthesized by the reaction of cyanacetamide with 3-dimethylaminomethylenebutyrolactone acetal. The indicated acetal can also react with amidine components to give furo [2,3-d]pyrimidine derivatives.
