Synthetic and theoretical studies on the reduction of electron withdrawing group conjugated olefins using the Hantzsch 1,4-dihydropyridine ester.
The Hantzsch 1,4-dihydropyridine ester (1) has been observed to be a useful selective reducing agent for the reduction of electron-withdrawing conjugated double bonds. The rate of this reaction was observed to be dependent upon the nature of the conjugated substituents and, consequently, the electronic nature of the unsaturated double bond. Theoretical calculations confirmed the importance of the HOMO-LUMO gap for this reaction and implicated a hydride transfer, agreeing with the experimentally observed reaction rate order. The calculations also revealed the importance of a boatlike structure of the 1,4-dihydropyridine nucleus as well as a trans arrangement of the ester groups to facilitate the hydride transfer.
Garden
Simon J
SJ
Departamento de Química Orgânica, Instituto de Química, Universidade Federal do Rio de Janeiro, Cidade Universitária, CT, Bloco A, Rio de Janeiro, RJ 21949-900, Brazil. garden@iq.ufrj.br
Guimarães
Cristiano Ruch Werneck
CR
Corréa
Marilza B
MB
de Oliveira
César Augusto Fernandes
CA
Pinto
Angelo da Cunha
Ada C
Bicca de Alencastro
Ricardo
R