Buchler Glossary

Asymmetric Henry Reaction (Nitroaldol Reaction)

The Henry reaction, also called Nitroaldol reaction, is a classic carbon–carbon bond formation reaction in organic chemistry. This kind of reaction is a base-catalyzed C-C bond-forming reaction between nitroalkanes and aldehydes or ketones. Because of its similarity with the aldol reaction it is also referred as the nitroaldol reaction. The Henry reaction of ketones has become one of the most important and versatile reactions for the construction of quaternary carbons containing hydroxyl and nitro groups.

The asymmetric Henry reaction can be accomplished by using a huge variety of Cinchona alkaloid based catalysts.

Asymmetric Henry reaction

A significant feature of the Henry reaction is a possibility to conduct the reaction enantio- or diastereoselectively using easily accessible Cinchona alkaloid catalysts. Chiral products of the Henry reaction, 2-nitroalcohols, are important intermediates in syntheses of many biologically active compounds. The core structure of the Cinchona alkaloid serves as an efficient enantioselective organocatalyst. Both stereoisomers can easily be synthesized enantioselectively using an organocatalyst from the blue or red Cinchona alkaloid series. The  asymmetric Henry reaction represents a powerful carbon-carbon bond-forming procedure for the preparation of valuable synthetic intermediates. The nitro alcohols can be further transformed in a number of important chiral amino alcohols.

Please review lots of examples for asymmetric Henry reactions in our free of charge Chiral Catalyst Search Data Base.

Example from Literature

Organocatalytic Enantioselective Henry Reactions. (Alvarez-Casao et al.; Symmetry 2011, 3, 220-245.)

Enantioselective Henry reaction

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