Henry反應(yīng)是指在堿催化下硝基烷烴與醛酮反應(yīng)β-羥基硝基烷烴的反應(yīng)。此反應(yīng)和羥醛縮合類似,也被稱為硝基Aldol反應(yīng)。
如果所得產(chǎn)物的酸性質(zhì)子存在的話(i.e. when R = H),產(chǎn)物很容易消除得到硝基烯烴。因此,如果想得β-羥基硝基化合物,必須用少量的堿作為催化劑。
反應(yīng)機(jī)理
最新文獻(xiàn)
A Highly Diastereo- and Enantioselective Copper(I)-Catalyzed Henry Reaction Using a Bis(sulfonamide)-Diamine Ligand
W. Jin, X. Li, B. Wan, J. Org. Chem., 2011, 76, 484-491.
A New Catalyst for the Asymmetric Henry Reaction: Synthesis of β-Nitroethanols in High Enantiomeric Excess
J. D. White, S. Shaw, Org. Lett., 2012, 14, 6270-6273.
Practical Asymmetric Henry Reaction Catalyzed by a Chiral Diamine-Cu(OAc)2 Complex
T. Arai, M. Watanabe, A. Yanagisawa, Org. Lett., 2007, 9, 3595-3597.
A New Copper Acetate-Bis(oxazoline)-Catalyzed, Enantioselective Henry Reaction
D. A. Evans, D. Seidel, M. Rueping, H. W. Lam, J. T. Shaw, C. W. Downey, J. Am. Chem. Soc.,2003, 125, 12692-12693.
Enantioselective Nitroaldol Reaction of α-Ketoesters Catalyzed by Cinchona Alkaloids
H. Li, B. Wang. L. Deng, J. Am. Chem. Soc., 2006, 128, 732-733.
Nitroaldol Reaction in Aqueous Media: An Important Improvement of the Henry Reaction
R. Ballini, G. Bosica, J. Org. Chem., 1997, 62, 425-427.
Hyperbranched Polyamines: Tunable Catalysts for the Henry Reaction
S. S. Ganesan, A. Ganesan, J. Kothandapani, Synlett, 2014, 25, 1847-1850.
Indium-Catalyzed Henry-Type Reaction of Aldehydes with Bromonitroalkanes
R. G. Soengas, A. M. S. Silva, Synlett, 2012, 23, 873-876.
A Convenient Samarium-Promoted Synthesis of Aliphatic (E)-Nitroalkenes under Mild Conditions
J. M. Concellón, P. L. Bernad, H. Rodríguez-Solla, C. Concellón, J. Org. Chem., 2007, 72, 5451-5423.
Highly anti-Selective Asymmetric Nitro-Mannich Reactions Catalyzed by Bifunctional Amine-Thiourea-Bearing Multiple Hydrogen-Bonding Donors
C.-J. Wang, X.-Q. Dong, Z.-H. Zhang, Z.-Y. Xue, H.-L. Teng, J. Am. Chem. Soc., 2008, 130, 8606-8607.
Aza-Henry Reaction of Ketoimines Catalyzed by Na2CO3: An Efficient Way to β-Nitroamines
L. Wang, C. Tan, X. Liu, X. Feng, Synlett, 2008, 2075-2077.
Electrochemically Induced Aza-Henry Reaction: A New, Mild, and Clean Synthesis of α-Nitroamines
L. Rossi, G. Bianchi, M. Feroci, A. Inesi, Synlett, 2007, 2505-2508.
編譯自:Organic Chemistry Portal
1985年,亨利首先發(fā)現(xiàn)了該反應(yīng),該反應(yīng)主要是硝基烷烴與醛或者酮類反應(yīng)生成硝基醇類化合物,此產(chǎn)物可以作為重要的中間體原料,用來(lái)制備多種化合物。特別是通過(guò)不對(duì)稱亨利反應(yīng)并進(jìn)一步還原得到手性的氨基醇類化合物,用于合成多種具有生物活性的醫(yī)藥中間體。
概要
在Perkin反應(yīng)、Darzens反應(yīng)、Aldol反應(yīng)等反應(yīng)中,羰基的α-負(fù)離子作為親核中間體進(jìn)行反應(yīng),而本反應(yīng)中是利用硝基烷烴的α-負(fù)離子進(jìn)行的反應(yīng)。由于硝基烷烴的α-氫的酸性比較高,所以只需要使用普通的胺作為堿就能使得該反應(yīng)在溫和的條件下進(jìn)行。
硝基烷烴可以用過(guò)接觸還原法還原成氨基,另外可以運(yùn)用Nef反應(yīng)把硝基轉(zhuǎn)換成羧酸來(lái)制備一些有用的合成中間體。
近年來(lái),利用不對(duì)稱催化劑特別是有機(jī)分子催化劑,開(kāi)發(fā)不對(duì)稱Henry反應(yīng)已經(jīng)成為一大熱點(diǎn)。
基本文獻(xiàn)
?Henry, L. Compt. Rend. 1895, 120, 1265.
反應(yīng)機(jī)理
反應(yīng)實(shí)例
直到現(xiàn)在各種改良法相繼還在被報(bào)道開(kāi)發(fā)中。在這些反應(yīng)中,摒棄高要求的強(qiáng)活化條件,即使在溫和的條件下也能催化該反應(yīng)進(jìn)行的催化劑被大量的開(kāi)發(fā)應(yīng)用。最近很多運(yùn)用有機(jī)催化劑進(jìn)行的不對(duì)稱反應(yīng)的例子被報(bào)道。以下給出其中的一例,合成金雞納生物堿的實(shí)例[1]
[1] Li H.; Wang, B.; Deng, L. J. Am. Chem. Soc. 2006,128, 732. DOI: 10.1021/ja057237l
本文轉(zhuǎn)自“化學(xué)空間”
硝基烷烴通過(guò)堿在α位脫掉質(zhì)子形成氮酸酯,進(jìn)而與醛進(jìn)行硝基羥醛縮合的反應(yīng)。
反應(yīng)機(jī)理
反應(yīng)實(shí)例
參考文獻(xiàn)
1. Henry, L. Compt. Rend. 1895, 120, 1265.
2. Matsumoto, K. Angew. Chem. 1984, 96, 599.
3. Sakanaka, O.; Ohmori, T.; Kozaki, S.; Suami, T.; Ishii, T.; Ohba, S.; Saito, Y. Bull.
Chem. Soc. Jpn. 1986, 59, 1753.
4. Barrett, A. G. M.; Robyr, C.; Spilling, C. D. J. Org. Chem. 1989, 54, 1233.
5. Rosini, G. In Comprehensive Organic Synthesis; Trost, B. M.; Fleming, I., Eds.; Pergamon,
1991, 2, 321