Synthesis of Δ2-pyrazolines precursors of pyrazolenines with different electrotractor substituents in C4 and C5. Photochemical evolution of formed dimethyl-3,3-pyrazolenines
Written by sctunisie no commentsThe 1.3-dipolar cycloaddition of diazo-2-propane (DAP) to diactivated dissymetric ethylene has enabled us to synthesize in good yield the homologous AH-pyrazolines. The oxidation of 3.3-dimethyl- Δ2-pyrazo-lines 6 and 7 with MnO, provides a new way of functionaling 3,3-dimethyl-pyrazolenines with electron attracting groups as substituents on C4 and C5. Similarly, the direct photolysis of functionalized pyrazolenines 8 and 9 also gives the gemdimethylcyclopropenes 12 functionalized.
A.K. Khemiss, M. Franck-Neumann
Pages 3-8
