Nitroaldol Henry Reaction

The nitroaldol condensation reaction involving aldehydes and nitronates, derived from deprotonation of nitroalkanes by bases. 

Name Reactions A Collection ofD ailed Mechanisms and Synthetic Applications, DOI 10.1007/978-3-319-03979-4 132, Springer International Publishing Switzerland 2014 

Example 4, A highly asymmetric Henry reaction catalyzed by chiral copper(ll) 

Westermann, B. Angew. Chem. Int. Ed. 2003, 42, 151-153. (Review on aza-Henry reaction). 

Henry Reaction. In Name Reactions for Homologations-Part 7 Li, J. J., Ed. Wiley Hoboken, NJ, 2009, pp 404-419. (Review). 

Rosini, G. In Comprehensive Organic Synthesis Trost, B. M. Fleming, I., Eds. Per-gamon, 1991, 2, 321-340. (Review). 

Name Reactions, 4th ed., DOI 10.1007/978-3-642-01053-8 124, Springer-Verlag Berlin Heidelberg 2009 

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The Henry (nitroaldol) reaction was reported under very mild reaction conditions, in aqueous media using a stoichiometric amount of a nitroalkane and an aldehyde, in NaOH 0.025 M and in the presence of cetyltrimethylammonium chloride (CTAC1) as cationic surfactant (Eq. 8.94) 240 Good to excellent yields of (i-nitroalkanol are obtained. Under these conditions several functionalities are preserved, and side-reactions such as retro-aldol reaction or dehydration of 2-nitroalcohols are avoided. 

Scheme 6.166 Product range of the asymmetric Henry (nitroaldol) reaction of aldehydes with various nitroalkanes in the presence of (S,S)-configured catalyst 183.

Scheme 6.170 Suggested transitions states for the anti-diastereoselective Henry (nitroaldol) reaction promoted by (R,R)-catalyst 186 (TS 1) and its (S,S)-isomer 183 (TS 2) to demonstrate the match/mismatch relationship between guanidine-thiourea catalyst and (S)-a-aldehyde.

Scheme 6.171 Product range of the 186-catalyzed anti-diastereoselective Henry (nitroaldol) reaction of a-chiral aldehydes with nitromethane.

Rosini, G. 1991. The Henry (nitroaldol) reaction. In Comprehensive Organic Synthesis. Trost, B.M., ed. Pergamon Press, Oxford, vol. 2, pp. 321 0. 

McNulty J, Cyck J, Larichev V, Capretta A, Robertson A (2004) Phosphonium salt catalyzed Henry nitroaldol reactions. Lett Org Chem 1 137-139... 

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