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This article is designed and synthesized a series of 4,4 ' - bit modified 2,2' - bipyridine ligand . 4,4 '- bis - ( bromomethyl ) -2,2 ' - bipyridine as raw material , obtained by N alkylation reaction five cationic modified 2,2 ' - bipyridine, yield 35% -98% ; polyethylene glycol monomethyl ether 750 , and 4,4 '- II - ( bromomethyl ) -2,2' - bipyridine occurs under alkaline conditions, the nucleophilic substitution reaction of the polyether chain was prepared a modified 2 2'- bipyridyl, 65% yield ; sodium sulfite and sodium 4,4 ' - two - ( bromomethyl ) -2,2 ' - bipyridine reaction generated anion modified (2,2 ' - bipyridyl -4 , 4' -) 2 - ( methylene- sulfonate) ( 40% yield ) . Characterization of the product by NMR, HR-MS (ESI) , the structure is correct. The design and synthesis of 2,2 ' - bipyridine ligand can be in the ionic liquid CuCl generated in situ copper complex , and is applied to the selective catalytic oxidation of piperonyl alcohol . In an oxygen atmosphere at 65 ° C for 12 hours the yield of 53% -94% . Wherein 4,4 ' - position having a polyether chain -modified 2,2' - bipyridine highest catalytic yield and cycle three times activity of the catalytic system was no significant reduction . In the study to 2,2 '- bipyridine as the three component coupling reaction process of the silver salt of the ligand catalyzed hydroformylation - secondary amine - alkynyl , cyclohexyl imidazole quaternary ammonium modified with surface exhibited the highest catalytic activity . On this basis , the paper further design and synthesis of five cyclohexyl methylene carbene silver complex , aromatic , and by NMR and X - ray crystallography of its structure determined . Cyclohexyl aryl methylenedioxy carbene silver complex in dioxane , 100 ° C under the conditions of catalytic hydrogenation of cinnamaldehyde - phenylacetylene - piperidine three component coupling reaction, and exhibited moderate to excellent catalytic efficiency ( 61% -99%). Wherein the N- cyclohexyl -N'- naphthyl alkylene having a single carbene structure A carbene silver chloride reaction for 2 hours , and the yield up to 99% . The substrate range of applications expandable aromatic aldehyde and fat alkyne .
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