29338-65-6Relevant academic research and scientific papers
Synthesis of Novel Pyrazoline Derivatives. I. Reaction of erythro-2,3-Dibromoketones with Semi- and Thiosemicarbazides
Elba,Darwish,Mamada
, p. 202 - 205 (2007/10/03)
The reaction of a series of ertyhro-2,3-dibromo-1,3-diaryl-1-porpanones with four molar equivalents of semicarbazide hydrochloride or thiosemicarbazide in dioxane or ethanol leads to the formation of trisubstituted pyrazolines and their 4-bromo derivatives. The pyrazolines have been identified by chemical and spectral data. A reaction mechanism is also proposed.
NMR spectra of trans-chalcone oxime, semicarbazone and thiosemicarbazone and their cyclic isomers (3,5-diphenyl-2-isoxazoline and 1-substituted 3,5-diphenyl-2-pyrazolines)
Balaban,Zugravescu,Avramovici,Silhan
, p. 704 - 708 (2007/10/04)
Earlier tentatively assigned structures for trans-chalcone oxime, semicarbazone and thiosemicarbazone, resp., have been corrected by means of NMR spectra: open-chain structures have been found for the title compounds formed in the acid catalyzed reaction, whereas basic catalysts lead to intramolecular cyclization with formation of 3,5-diphenyl-2-isoxazoline and 1-substituted 3,5-diphenyl-2-pyrazolines resp. Assignments in the NMR spectra were made by comparison with those from authentic samples of trans-dypnone and its semicarbazone.
