DNA-catalyzed Henry reaction in pure water and the striking influence of organic buffer systems.
In this manuscript we report a critical evaluation of the ability of natural DNA to mediate the nitroaldol (Henry) reaction at physiological temperature in pure water. Under these conditions, no background reaction took place (i.e., control experiment without DNA). Both heteroaromatic aldehydes (e.g., 2-pyridinecarboxaldehyde) and aromatic aldehydes bearing strong or moderate electron-withdrawing groups reacted satisfactorily with nitromethane obeying first order kinetics and affording the corresponding β-nitroalcohols in good yields within 24 h. In contrast, aliphatic aldehydes and aromatic aldehydes having electron-donating groups either did not react or were poorly converted. Moreover, we discovered that a number of metal-free organic buffers efficiently promote the Henry reaction when they were used as reaction media without adding external catalysts. This constitutes an important observation because the influence of organic buffers in chemical processes has been traditionally underestimated.
Institute of Organic Chemistry, University of Regensburg, Universitätsstr. 31, Regensburg 93053, Germany. Marleen.Haering@chemie.uni-regensburg.de.
Marleen
M
Häring
Institute of Organic Chemistry, University of Regensburg, Universitätsstr. 31, Regensburg 93053, Germany. Maria-del-Mar.Perez-Madrigal@chemie.uni-regensburg.de.
Maria M
MM
Pérez-Madrigal
Institute of Organic Chemistry, University of Regensburg, Universitätsstr. 31, Regensburg 93053, Germany. dennis.kuehbeck@gmx.de.
Dennis
D
Kühbeck
Institute Charles Gerhardt Montpellier-UMR 5253 CNRS-UMII-ENSCM-UMI, Matériaux Avancés pour la Catalyse et la Santé, 8 rue de l'École Normale, 34296 Montpellier Cedex 5, France. asja.pettignano@enscm.fr.
Asja
A
Pettignano
Institute Charles Gerhardt Montpellier-UMR 5253 CNRS-UMII-ENSCM-UMI, Matériaux Avancés pour la Catalyse et la Santé, 8 rue de l'École Normale, 34296 Montpellier Cedex 5, France. francoise.quignard@enscm.fr.
Françoise
F
Quignard
Institute of Organic Chemistry, University of Regensburg, Universitätsstr. 31, Regensburg 93053, Germany. David.Diaz@chemie.uni-regensburg.de.|IQAC-CSIC, Jordi Girona 18-26, Barcelona 08034, Spain. David.Diaz@chemie.uni-regensburg.de.
David Díaz
DD
Díaz
D000447:Aldehydes / Q000737:chemistry*; D002021:Buffers; D002384:Catalysis; D004247:DNA / Q000737:chemistry*; D004583:Electrons; D006575:Heterocyclic Compounds, 3-Ring / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D009574:Nitro Compounds / Q000737:chemistry*; D009595:Nitroparaffins / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
D000447:Aldehydes; D002021:Buffers; D006575:Heterocyclic Compounds, 3-Ring; D009574:Nitro Compounds; D009595:Nitroparaffins; C560828:nitroaldol; D014867:Water; D004247:DNA; D008697:Methane; C008640:nitromethane