54818-68-7Relevant articles and documents
Chitosan based heterogeneous catalyses: Chitosan-grafted-poly(4- Vinylpyridne) as an efficient catalyst for michael additions and alkylpyridazinyl carbonitrile oxidation
Khalil, Khaled D.,Al-Matar, Hamad M.
, p. 5288 - 5305 (2013/07/19)
Chitosan-grafted-poly(4-vinylpyridine) (Cs-PVP) copolymers could be synthesized under heterogeneous conditions in presence of a potassium persulfate and sodium sulfite redox system. The synthesized graft copolymer could be utilized effectively, in the form of beads, as an efficient catalyst for Michael additions of active methylenes to functionally substituted alkenes. Moreover, methyl moiety oxidation in methyl pyridazinyl carbonitriles by H 2O2 in the presence of chitosan-g-polyvinyl pyridine-supported iron (III) complex, Cs-PVP/Fe, could be affected. A variety of pyrans, naphthopyrans, and thiopyrans could be synthesized efficiently in the presence of these graft copolymer beads by novel catalytic routes. These polymeric catalysts could be used instead of the old toxic commercial organic basic catalysts, piperidine or pyridine, and could be readily isolated from the reaction mixture and recycled several times without significant loss of catalytic activity.
Enaminones as building blocks in heterocyclic syntheses: Reinvestigating the product structures of enaminones with malononitrile. A novel route to 6-substituted-3-oxo-2,3-dihydropyridazine-4-carboxylic acids
Alnajjar, Abdul-Aziz,Abdelkhalik, Mervat Mohammed,Al-Enezi, Amal,Elnagdi, Mohamed Hilmy
experimental part, p. 68 - 77 (2009/08/15)
The reported structures of reaction products of enaminones with malononitrile in ethanolic piperidine are revised. A novel route to 2,3-dihydropyridazine-4-carboxylic acids 4a-c via reactions of 2-cyano-5-(dimethylamino)-5-arylpenta-2,4-dienamides 8a-c wi
