RESUMO
The absolute configurations of cis-dihydrodiol bacterial metabolites derived from quinoline substrates and their quinolinium salts have been determined by comparison of experimental and calculated chiroptical data (circular dichroism spectra and optical rotations). The role of intramolecular H-bonding and other interactions in the preferred conformations has been investigated, including the effect of protonation of several cis-dihydrodiols. The presence of a strong intramolecular OH...N bond in several cis-dihydrodiol metabolites suggests that such species have a residually chiral oxygen atom.
Assuntos
Conformação Molecular , Naftalenos/química , Nitrogênio/química , Quinolinas/química , Dicroísmo Circular , Simulação por Computador , Ligação de Hidrogênio , Naftalenos/metabolismo , Rotação Ocular , Quinolinas/metabolismo , Espectrofotometria Ultravioleta , Sphingomonas/metabolismo , Estereoisomerismo , Especificidade por SubstratoRESUMO
Biphenyl dioxygenase-catalysed cis-dihydroxylation of 2-chloroquinoline, 2-chloro-3-methylquinoline and 2-chloro-6-phenylpyridine substrates yielded the corresponding enantiopure cis-dihydrodiols; enantiopure 2,2'-bipyridines, synthesised in four steps from 2-chloroquinoline, proved to be efficient chiral ligands in catalytic asymmetric allylic oxidation and cyclopropanation reactions of alkenes.
Assuntos
2,2'-Dipiridil/química , Compostos Alílicos/síntese química , Compostos Aza/química , Ciclopropanos/síntese química , Naftalenos/química , 2,2'-Dipiridil/síntese química , Alcenos/química , Compostos Alílicos/química , Compostos Aza/síntese química , Catálise , Cristalografia por Raios X , Ciclização , Ciclopropanos/química , Dioxigenases/química , Ligantes , Modelos Moleculares , Estrutura Molecular , Naftalenos/síntese química , Oxirredução , EstereoisomerismoRESUMO
The first enantiopure 4,4'-bipyridyls, , , and have been prepared in four or five steps via bacterial dioxygenase-catalysed cis-dihydroxylation of 4-chloroquinoline and C-C coupling; ligands and are found to be effective building blocks for the preparation of chiral metal-organic frameworks as demonstrated with the rational synthesis of two pillared-grid structures [Zn(2)(fumarate)(2)(L)], which exhibit interesting structural and dynamic aspects.
