Search results

Sort By:

Limit search:

Use of (R)-Mandelic Acid as Chiral Co-Catalyst in the Michael Addition Reaction Organocatalyzed by (1S,4S)-2-Tosyl-2,5-diazabicyclo[2.2.1]heptane under Solvent-Free Conditions

100%

Ávila-Ortiz C. G., López-Ortiz M., Vega-Peñaloza A., Regla I., Juaristi E.

Asymmetric Catalysis

2015

vol. 2

issue 1

This article describes a study on the Michael addition reaction of cyclohexanone to nitroolefins catalyzed by the chiral secondary amine (1S,4S)-2-tosyl- 2,5-diazabicyclo[2.2.1]heptane. Reactions were carried out under solvent-free conditions to make them more environmentally friendly. Initially, the observed diastereoand enantioselectivities were moderate to good, but were significantly improved by lowering the reaction temperature. Furthermore, a variety of chiral acids were also tested as co-catalysts in both of their enantiomeric forms, which revealed that (R)-mandelic acid affords excellent results in terms of yield and stereoselectivity. Monitoring the reaction by MS-TOF allowed for the detection of key reaction intermediates, and a reasonable reaction mechanism in which both catalysts are involved is proposed.

Refine search results

1 Asymmetric Catalysis

1 2015

1 Juaristi E.

1 López-Ortiz M.

1 Regla I.

1 Vega-Peñaloza A.

1 Ávila-Ortiz C. G.

Search results

Use of (R)-Mandelic Acid as Chiral Co-Catalyst in the Michael Addition Reaction Organocatalyzed by (1S,4S)-2-Tosyl-2,5-diazabicyclo[2.2.1]heptane under Solvent-Free Conditions