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二乙酰一肟(Diacetyl monoxime,简写为DAM)均相加氢反应的产物四甲其吡嗪(Tetramethllpyrazine,简写为TMP)是一种多用广泛用作调味剂、香味剂[1],也是一种功能很强的光敏剂,并发现其可用于治疗脑血栓、冠心病、脉管炎等多种闭塞性血管疾病,现已开始用于临床[2]. 相似文献
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邻酰氧基取代苯甲醛和苯甲醇在硼氢化钠水溶液中的还原反应 总被引:1,自引:0,他引:1
邻位上含有苯甲酰氧取代基的苯甲醛化合物2,5-双[(4-甲氧基苯甲酰)氧基]苯甲醛用NaBH~4还原时,产物与体系中是否含水有重要关系.在无水的情况下,还原按正常的方式进行,并生成相应的苯甲醇化合物;在有水的情况下,醛基首先被还原成醇,接着被还原成甲基,同时发生邻位(而不是间位)苯甲酰氧基的水解,产物为邻甲基酚类化合物.模型化合物邻(对甲氧基苯甲酰)氧基苯甲醛和间(对甲氧基苯甲酰)氧基苯甲醛的反应证实了上述发现.这一特殊反应可以推广到邻位上含有酰氧取代基的基本甲醛及其相应的醇. 相似文献
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介绍了一个以(S)-脯氨酸为有机小分子催化剂的不对称交叉aldol缩合反应实验。在(JS)-脯氨酸催化下,对硝基苯甲醛和丙酮发生aldol缩合反应,生成具有光学活性的β-羟基酮产物,并通过谱学方法和比旋光度的测定进行表征。讨论了该实验在高年级本科生科研训练教学工作中的实践效果。 相似文献
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氨基二苯硒的酰化和缩合反应研究 总被引:6,自引:1,他引:6
4-氨基二苯硒分别与酸酐和醛进行酰化反应和缩合反应,合成了6种N-二苯硒胺羰基苯甲酸及12个,N-二苯硒亚胺化合物,用元素分析,红外光谱,核磁共振谱表征了结构,结果表明在酰化反应和缩合反应中,4-氨基二苯硒与芳伯胺及氨基二茂铁的作用相同,产物结构类似,且均具有生物活性。 相似文献
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合成了一种新的对硝基苯甲醛缩对羟基苯甲酰腙晶体;利用红外光谱、紫外光谱和元素分析对其进行了表征,并利用单晶X射线衍射测定了其晶体结构.结果表明,该晶体属于单斜晶系,P2(1)/n空间群;晶胞参数a=0.766 17(2)nm,b=1.357 3(3)nm,c=1.256 0(3)nm,β=92.71(3)°,V=1.304 7(4)nm3,Z=4,Dc=1.452 g/cm3,μ=0.109 mm-1.12 593个可观察独立衍射点(I2σ(I))偏离因子R1=0.042 5,wR2=0.142 4,S=1.096. 相似文献
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合成了 2 羟基 4 磺酰氨基苯重氮氨基偶氮苯 (HSDAA) ,并研究了在TritonX 1 0 0表面活性剂存在下HSDAA与镉的显色反应。在pH 8 5~ 1 0 5的Na2 B4 O7 NaOH缓冲溶液中 ,该试剂与镉生成 2∶1型深红色配合物。配合物的最大吸收峰位于 5 2 5nm处 ,表观摩尔吸光系数达 1 84× 1 0 5L·mol- 1·cm- 1。ρ(Cd2 + )在 0~ 480 μg/L范围内符合比耳定律。用拟定方法测定样品中的微量镉 ,结果满意。 相似文献
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1 引言分子筛作为催化剂由于其特殊的酸性和择形性在精细有机合成中获得了广泛的应用[1],在缩醛化反应中也表现出了良好的催化性能,如Joshi[2]等用HY和HZSM5分子筛作催化剂,将苯甲醛与甲醇缩合,获得了83%的苯甲缩甲醛,并考察了不同种类的醛在HZSM5分子筛上的择形性。王存... 相似文献
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The use of ultrasonic irradiation to improve the yield and to shorten the reaction time of aldol dimerization of ketones catalyzed with basic alumina is described. 相似文献
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Amitava Acharjya Pradip Pachfule Jrme Roeser Franz‐Josef Schmitt Arne Thomas 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(42):15007-15012
Two 2D covalent organic frameworks (COFs) linked by vinylene (?CH=CH?) groups (V‐COF‐1 and V‐COF‐2) are synthesized by exploiting the electron deficient nature of the aromatic s‐triazine unit of C3‐symmetric 2,4,6‐trimethyl‐s‐triazine (TMT). The acidic terminal methyl hydrogens of TMT can easily be abstracted by a base, resulting in a stabilized carbanion, which further undergoes aldol condensation with multitopic aryl aldehydes to be reticulated into extended crystalline frameworks (V‐COFs). Both V‐COF‐1 (with terepthalaldehyde (TA)) and V‐COF‐2 (with 1,3,5‐tris(p‐formylphenyl)benzene (TFPB)) are polycrystalline and exhibit permanent porosity and BET surface areas of 1341 m2 g?1 and 627 m2 g?1, respectively. Owing to the close proximity (3.52 Å) of the pre‐organized vinylene linkages within adjacent 2D layers stacked in eclipsed fashion, [2+2] photo‐cycloadditon in V‐COF‐1 formed covalent crosslinks between the COF layers. 相似文献
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不同金属四苯基卟啉(TPPM)催化氧化苯甲醛时,TPPMnOAc催化活性最高,TPPFeCl次之,TPPCo和TPPNi几乎无活性;TPPMnOAc苯环上吸电子取代基的存在有利于提高其催化活性和稳定性,苯环上邻位吸电子取代基能明显提高四苯基锰卟啉的稳定性,但由于空间位阻的原因,使其催化活性降低.在本模拟体系中,T(2,6 di Cl)PPMnOAc是一个较理想的催化剂. 相似文献
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The investigation of the chemistry of indoles has been, and continues to be, one of the most active areas of heterocyclic chemistry.[1] In particular, β-indolylketones have received much attention as important building blocks for the synthesis of many natural products and other biologically active compounds.[2] In continuation of our work in the synthesis of indole derivates,[3] we describe the remarkable catalytic of PTSA as a cheaper catalyst in ultrasound-accelerated Michael reaction of indole with α, β-unsaturated ketones (2), which provide one of the most efficient routes to the synthesis of β-indolyketones. In all cases, the substitution on the indole nucleus occurred exclusively at the 3-position, and N-alkylation products have not been observed. In addition, the structure of 3a was further confirmed by single crystal X-ray crystallography. 相似文献
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KANG Yong-feng Wang Rui Liu Lei Yan Wen-jin Xu Zhao-qing ZHOU Yifeng Chen Chao Tang Ning Xu Jiangke 《合成化学》2004,12(Z1)
The enantioselective alkynylzinc addition to aldehydes is very useful for the synthesis of chiral propargyl alcohols which are important versatile building blocks of many biologically active compounds and natural products1. A series of chiral oxazolidines were conveniently synthesized from amino acids in three steps with good yields. The use of chiral Lewis acid ligand: zinc-amide complex in situ generated from this oxazolidine with alkylzinc as chiral catalysts for the enantioselective alkyny… 相似文献
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含席夫碱双环氮杂锡氧烷配合物的结构与VB6酶体系结构相似。以含席夫碱二苯基锡配合物(PhSnL1H)为研究对象,测定了二苯基锡配合物(PhSnL1H)在DMSO中的pKa(17.60),同时研究了该配合物与醛的缩合反应,合成了7种新的含β-羟基-α-氨基酸配体的有机锡配合物(PhSnL1CHOHRⅠ~Ⅶ),并由IR、1HNMR、119SnNMR及元素分析等确定了配合物的结构。 相似文献