Uroš Uršič, Uroš Grošelj, A. Meden
2009
Citations
0
Influential Citations
2
Citations
Journal
Synthesis
Abstract
Methyl ( Z)-2-(benzoylamino)-3-(dimethylamino)propenoate( 1) reacted with trimethylenemethane ( 2) to produce methyl ( Z)-2-[benzoyl(2-methylallyl)amino]-3-(dimethylamino)propeno-ate( 3), which was then converted into pyrazolederivatives 11A- H bya consecutive exchange of the dimethylamino group with hydrazinederivates 9A- H andcyclization to the ester group. Reactions of pyrazoles 11A- G withdimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate ( 6)resulted in the diastereoselective formation of 1-aryl-6′-benzoyl-4a′-methyl-5-oxo-1,4′,4a′,5,5′,6′-hexahydrospiro[pyrazole-4,7′-pyrrolo[3,4- C]pyridazine]-3′,7a′(1′ H)-dicarboxylates 12A- G. This represents a simple new pathwayto novel heterocyclic systems. On the other hand, when (dimethylamino)propenoate 3 reacted with aniline hydrochloride ( 4), followed by the cycloaddition of 1,2,4,5-tetrazine 6, dimethyl ( E)-and ( Z)-4-({benzoyl[1-(methoxycarbonyl)-2-(phenylamino)vinyl]amino}methyl)-4-methyl-1,4-dihydropyridazine-3,6-dicarboxylates( 7) and ( 8) wereformed, respectively.