Michael Addition of Nitroalkanes to CF_3CCl_2COCH=CHPh: A Facile Route to Fluorine-containing γ-Nitro Ketones

Nitroalkanes react smoothly with CF_3CCl_2COCH=CHPh via Michael addition in the presence of inorganic bases such as KF/Al2O3 or K2CO3, giving fluorinecontaining γ-nitro ketones in good yields.

Novel chiral thioureas for highly enantioselective Michael reactions of malonates to nitroalkenes

Highly efficient Michael addition reactions of malonates to nitroalkenes catalyzed by novel chiral thioureas derived from optically pure BINOL and amino acids are reported. Various trans-nitroalkenes reacted with malonates affording the desired products in up to 95% yield with excellent enantioselectivities （up to 97% ee）.

Density Functional Calculations of C–NO_2 Bond Dissociation Energies for Nitroalkanes Molecules

Bond dissociation energies for the removal of nitrogen dioxide group in some nitroalkane energetic materials have been calculated by using the three hybrid density functional theory （DFT） methods B3LYP, B3PW91 and B3P86 with 6-31g^＊＊ and 6-311g^＊＊ basis sets. The computed BDEs have been compared with the available experimental results. It is found that the B3P86 method with 6-31g^＊＊ and 6-311g^＊＊ basis sets can obtain satisfactory bond dissociation energies （BDEs）, which are in extraordinary agreement with the experimental data. Considering the smaller mean absolute deviation and maximum difference, the reliable B3P86/6-311g^＊＊ method was recommended to compute the BDEs for the removal of nitrogen dioxide group in the nitroalkane energetic materials. Using the method, the BDEs of 8 other nitroalkane energetic materials have been calculated and the maximum difference from experimental value is 1.76 kcal.mo1^-1 （for the BDE of tC4Hg-NOz）, which further proves the reliability of B3P86/6-311g^＊＊ method. In addition, it is noted that the BDEs of C-NO2 bond change slightly for main chain nitroalkane compounds with the maximum difference of only 3.43 kcal mo1^-1.

A Facile and Efficient Synthesis of Substituted Pyrroles by Three Component Coupling Reaction of Amines, Aldehydes and Nitroalkanes

A facile and efficient synthesis of highly substituted pyrroles has been achieved by a one-pot three-component coupling reaction of aldehyde, amine and nitroalkane by triethyl orthoformate.

Mn(OAc)_2/Schiff base as a new efficient catalyst system for the Henry reaction of nitroalkanes with aldehydes

A series of novel Schiff bases bearing triazole structure were synthesized and characterized by LR and NMR. Mn（OAc）2/Schiff base efficiently catalyzed Henry reaction of nitroalkanes with aldehydes to produce the corresponding products of ^-nitroalcohols, under mild conditions with high yields （up to 99%）. A reaction mechanism is proposed based on the experimental results.

FriedeI-Crafts Alkylation of Indoles with Nitroalkenes Catalyzed by Zn（II）-Thiourea Complex

Friedel-Crafts alkylation of indoles with nitroalkenes catalyzed by a novel Zn（II）-thiourea complex has been developed. The remarkable advantages of this reaction are mild reaction conditions, simple workup procedure, high yield of products and the use of ethanol as acceptable solvent.

Friedel-Crafts alkylation of indoles with nitroalkenes catalyzed by Cu(Ⅱ)-imine complex

A series of new ligands L_1-L_7 were readily prepared in one step.Friedel-Crafts alkylation of indoles with nitroalkenes catalyzed by a novel Cu（Ⅱ）-L complex has been developed.The remarkable advantages of this reaction are mild reaction conditions,simple workup procedure,high yields of products and the use of ethanol as a green solvent.

Ethylenediamine： A Highly Effective Catalyst for One-Pot Synthesis of Aryl Nitroalkenes via Henry Reaction and Dehydration

Ethylenediamine （H2NCH2CHeNH2） was found to be a highly effective catalyst for the condensation of aryl aldehydes with nitromethane （or nitroethane）. When 1%-2% （tool%） of ethylenediamine was used as the catalyst, the one-pot reaction of aryl aldehydes with nitromethane （or nitroethane） by refluxing for 3-10 h efficiently afforded various arylnitroalkenes la-ly in 85%-97% yields.

Aqueous-mediated Michael Addition of Active Methylene Compounds with Nitroalkenes

A simple, atom economical and highly efficient green protocol has been developed for the synthesis of Michael adducts of nitroalkenes and 2-amino-2-chromene derivatives by Michael addition of active methylene compounds （such as malononitrile and ethyl cyanoacetate） to nitroalkenes under aqueous-mediated conditions. This green approach provided the desired products in high yields and the reaction scope proved to be quite broad.

Indium Mediated Conjugate Addition of Allyl Bromide to Nitroalkenes in DMF-H_2O Media

Allylindium bromide prepared by metallic indium and allyl bromide was added to nitroalkenes to give conjugate addition compounds in moderate to good yields in an aqueous media.

Synthesis of Substituted Pyrroles via Ultrasound Assisted Three-component Coupling Reaction of Amines, α,β-Unsaturated Aldehydes and Nitroalkanes

An efficient synthesis of substituted pyrroles via ultrasound assisted three component coupling reaction of amines with α,β unsaturated aldehydes and nitroalkanes is reported.

合成α-芳基-β-硝基乙基膦酸酯的新方法

本文研究了酸性亚磷酸酯与α-芳基-β-硝基烯烃在三甲基氯硅烷和缚酸剂存在下的Arbuzov-Michael反应。不需制备硅烷化的亚磷酸酯,即可得到产率高的Ia-n,其结构由元素分析、IR、1H NMR和MS证实。这类分子中磷原子上的O,O-二烷基为磁不等价基团的结论亦为X-射线晶体结构分析所证实。

L-脯氨酸对离子液体介质中的不对称Michael反应催化性能研究

研究了L-脯氨酸对离子液体介质中醛(酮)与β-硝基烯烃的不对称Michael加成反应的催化性能,利用X射线单晶衍射对Michael产物结构进行了表征.结果表明,反应在遵循胺催化机理的同时,烯胺是从Re面对β-硝基烯烃进行加成,产物的优势结构为(1R,2S)的syn型.脯氨酸在离子液体1-正己基-3-甲基咪唑氯盐中显示良好的催化性能,室温反应3～5h,得到89%以上收率的Michael产物,其ee值最高70%.脯氨酸与离子液体形成的催化体系具有良好的重复使用性能,可至少稳定地重复使用6次.

硝基烷烃与醛类合成氨基醇及其用途

介绍了甲醛与硝基甲烷反应合成几种氨基醇类的产品发展情况及其用途。

圈卷产色链霉菌硝基烷类氧化酶的分离纯化及酶学性质

圈卷产色链霉菌硝基烷类氧化酶基因naoA在大肠杆菌中获得了成功表达 ,从含有重组质粒pNA1 0 1 (pET2 3b∷naoA)的工程菌株BL2 1 (DE3 )中分离纯化了硝基烷类氧化酶 ,SDS PAGE检测为均一。对纯酶进行了酶学性质及动力学研究。底物为 1 硝基丙烷、2 硝基丙烷和硝基乙烷时 ,在 0 4mol L的磷酸缓冲液中 ,酶的最适反应pH值为 7～ 8,最适反应温度为48℃～ 5 6℃。室温保存 6d后 ,酶的活性保持了 43 3 % ,但对 6 0℃以上的高温敏感。硫醇化合物如巯基乙醇、还原型谷胱甘肽不同程度地抑制酶活性 ,特别是NADH ,其浓度为 1mmol L时 ,酶活性几乎全部丧失。以 1 硝基丙烷为底物时 ,NaoA的Km 为 3 5 7mmol L ,Vmax 为0 1 99μmol (μg .min) 。

丙烷硝化液相产物分离工艺初探

本文简要介绍了硝基烷烃的性质及用途,采用萃取方法对丙烷硝化液相产物中水相产物进行精制,利用精馏技术对油相产物进行组分分离操作,考察了切割温度、回流比、塔板数对各组分含量及馏出率的影响。实验结果表明,不同的切割温度对各组分的有效含量影响较大,随着回流比和塔板数的增大,各组分的含量明显提高,馏出率提高,但相应的能耗增加明显,通过精馏分离,硝基烷烃各组分都能达到使用要求。

一种新颖的α-苄基取代硝基烯的合成方法

硝基烯是一种非常有用的有机中间体,广泛用于有机合成中,但是近年的研究主要集中β取代硝基烯,α取代硝基烯研究甚少,本文就研究出一种可以简便易行适合工业化生产的合成α取代硝基烯的方法。

无溶剂球磨法合成γ-硝基酯化合物

采用球磨法在无溶剂条件下用硝酸钙促进硝基烯烃与丙二酸酯发生迈克尔加成反应,从而合成γ-硝基酯化合物。该反应在频率为20 Hz下进行,30 min即可完全转化。硝基烯烃及其衍生物与丙二酸酯反应可得到产率80%以上的目标产物,尤其当硝基苯乙烯苯环上的邻位有两个吸电子基时,产率可达95%。

金鸡纳生物碱催化的共轭硝基烯与活性醛的不对称Morita-Baylis-Hillman反应

目的:创建共轭硝基烯与活性醛的不对称Morita-Baylis-Hillman(MBH)反应催化体系,筛选具有高催化活性及对映选择性的手性催化剂。方法:将21种手性有机小分子催化剂应用于β-硝基苯乙烯与乙醛酸乙酯的不对称MBH反应中,用手性高效液相色谱分析测定产物ee值,并考察温度、溶剂、底物比例等因素对催化反应的影响。结果:在金鸡纳生物碱类催化剂(DHQ)2AQN作用下,β-硝基苯乙烯与乙醛酸乙酯在甲苯中0℃下反应,获得光学纯度为56.9%ee的MBH加成产物,化学产率为60%。结论:以芳香基团作为桥联基的双金鸡纳生物碱类催化剂能够有效地催化β-硝基苯乙烯与乙醛酸乙酯的不对称MBH反应顺利进行,并获得中等程度的化学分离产率及对映选择性。