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1.
Long-chain saturated fatty aldehydes (C10 to C18), as well as the C18 unsaturated aldehydes (oleyl, linoleyl, and linolenyl), were synthesized in good yields by the selective oxidation of the sulfonate esters of the corresponding alcohols with dimethyl sulfoxide in the presence of sodium bicarbonate. Chromatographic procedures for the isolation of the pure aldehydes from the reaction mixtures are described. The purity of the aldehydes was ascertained by thin-layer chromatography, melting points of their 2,4-dinitrophenyl hydrazones, infrared spectra and other physical methods. Presented at the AOCS Meeting in Houston, April, 1965.  相似文献   

2.
李艳春  张鹏会 《广东化工》2014,(15):32-33,22
主要研究了以四氢呋喃作为反应溶剂,三甲基氯硅烷作为活化剂,金属铟促进下醛与烯丙基溴生成高烯丙基醇的反应。讨论了三甲基氯硅烷的用量及了不同反应底物对反应的影响,得出反应的最佳条件是三甲基氯硅烷与醛的比2/1,并且发现只有吸电子基及卤素取代的芳香醛反应速度较快,收率好,其它醛的反应较复杂。  相似文献   

3.
芳香醛和芳香胺参予的Mannich反应及其合成应用   总被引:2,自引:0,他引:2  
肖敏  村松Y^b 《化学试剂》1997,19(1):8-11
研究了芳香胺和芳香醛参予的Mannich反应及其合成应用,以它们的原料合成了10余种新的Mannich碱,也使Mannich反应由单一甲醛扩展到芳香醛,产率为62.3%~90.4%。  相似文献   

4.
Reactions of Bis-enamines with Aldehydes - New Synthesis of 1,3-Oxazines and Pyridines In the presence of phosphoric acid N-alkyl-dipropenylamines react with aliphatic aldehydes to form substituted 1,3-oxazines. With benzaldehyde this reaction does not proceed, but azomethines are formed. N,N-dipropenylaniline with aldehydes also gives azomethines, a dihydropyridine is formed as well. From tripropenylamine and aldehydes substituted pyridines are obtained.  相似文献   

5.
The oxidation process of olive, hazelnut, and peanut oils at 70°C with circulating air has been studied by means of 1H NMR. The evolution of the process, including the rate of degradation of the acyl groups and of formation and degradation of primary oxidation products, as well as the rate of formation of secondary oxidation products such as aldehydes, is commented on and compared with the oxidation of oils rich in polyunsaturated acyl groups. Differences that are due not only to the rate of the processes but also to the nature and concentration of the generated aldehydes are observed. Oils rich in monounsaturated acyl groups generate smaller amounts of the geno-and cytotoxic oxygenated aldehydes than oils rich in polyunsaturated acyl groups.  相似文献   

6.
刘长春 《精细化工》2012,(8):778-782
制备了3种Brnsted酸离子液体:1-甲基-3-(3-磺丙基)咪唑硫酸氢盐([SO3H-pmim]HSO4)、1-(3-磺丙基)吡啶硫酸氢盐([SO3H-ppy]HSO4)、N-(3-磺丙基)三乙基铵硫酸氢盐([SO3H-ptea]HSO4),用于催化邻氨基苯乙酮和芳香醛的反应一锅法合成2-芳基-2,3-二氢-4(1H)-喹啉酮,考察了它们的催化活性和重复使用性能。结果表明,3种离子液体对邻氨基苯乙酮和芳香醛的反应均具有较高的催化活性,以[SO3H-ptea]HSO4催化性能更好。在60℃和无溶剂条件下,[SO3H-ptea]HSO4可以有效催化邻氨基苯乙酮和不同芳香醛反应,以68.3%~95.1%的收率得到目标化合物。离子液体经真空干燥重复使用5次,催化活性无明显下降。  相似文献   

7.
alpha,beta-unsaturated aldehydes are toxic products of lipid peroxidation. Detection and characterization of these aldehydes is important in many human disease states as well as in the food industry. Our study shows that electron ionization-mass spectrometry (EI-MS) and positive-ion chemical ionization-mass spectrometry (PICI-MS), but not electron capture negative ionization-mass spectrometry (ECNI-MS), can be used to detect the C4-hydroxylation state of alpha,beta-unsaturated aldehydes derivatized with pentafluorobenzyl hydroxylamine alone. EI-MS and PICI-MS spectra of 4-hydroxy-2-alkenals contained a fragment with m/z 252, whereas spectra of 2-alkenals contained a fragment with m/z 250. These fragments are consistent with fragmentation between C3 and C4 with transfer of two hydrogens from C4 and the C4 hydroxyl group in the case of 4-hydroxy-2-alkenals. In addition, EI-MS and PICI-MS were able to distinguish 4-hydroxy-2-alkenals and 2-alkenals from 4-keto-2-alkenals and 4-hydroxyalkanals. On the other hand, ECNI-MS provided complex spectra regarding C4-hydroxylation state. Furthermore, the syn- and anti-configurations of PFB-oximes had different resultant spectra using ECNI-MS, but not with EI-MS or PICI-MS. These data indicate that EI-MS and PICI-MS are more amenable for structural analysis of alpha,beta-unsaturated aldehydes than ECNI-MS.  相似文献   

8.
This account highlighted the recent advances of our research on the synthesis of enantiopure 2-amino-2′-hydroxy-1,1′-binaphthyl (NOBIN) and its derivatives as well as their applications in asymmetric catalysis, including diethyl zinc addition to aldehydes, allylic addition to aldehydes, allylic substitutions, and hetero-Diels–Alder reactions.  相似文献   

9.
Antennally active, bark-derived, angiosperm volatiles were tested singly and in groups for their ability to disrupt the response of the Douglas-fir beetle (DFB), Dendroctonus pseudotsugae, to attractant-baited multiple-funnel traps. One compound, conophthorin, was active alone in reducing the response of beetles to the baited traps. Further experiments showed disruptive activity in two aliphatic green-leaf alcohols [1-hexanol and (Z)-3-hexen-1-ol], as well as guaiacol and benzyl alcohol, and three aliphatic aldehydes [nonanal, hexanal, and (E)-2-hexenal] but not in two aromatic aldehydes (benzaldehyde and salicylaldehyde). Every binary combination that included conophthorin or any two of the other groups, except aromatic aldehydes, significantly reduced the response of beetles to baited traps. Various ternary mixtures and the complete mixture of all the groups were generally the most effective treatments. These results provide evidence that DFBs recognize and avoid nonhosts while flying rather than landing on candidate hosts and testing them while in contact with the tree. Nonhost angiosperm bark volatiles may have practical utility on their own or in combination with the antiaggregation pheromone 3-methylcyclohex-3-en-1-one (MCH) to protect single trees, logs, or stands from attack by the DFB.  相似文献   

10.
An organocatalytic Michael addition of protected 2‐amino‐1‐nitroethanes to α,β‐unsaturated aldehydes followed by treatment with TFA afforded 4‐substituted 3‐nitro‐1,2,3,4‐tetrahydropyridines with good diastereoselectivity and excellent enantioselectivity. Good yields were observed in the case of β‐aryl‐substituted α,β‐unsaturated aldehydes as the substrates, while moderate yields were obtained when β‐alkyl‐substituted α,β‐unsaturated aldehydes were used.  相似文献   

11.
Bark volatiles from two peach cultivars (Bisco and Redskin) were obtained by vacuum steam distillation and fractionated by preparative gas chromatography. The fractions were then assayed with the electroantenno- gram (EAG) method on antennae of female lesser peachtree borer [Synanthedon pictipes (Grote and Robinson)]. With both cultivars, two fractions elicited the largest responses. Analysis of this material by GC-MS revealed a complex mixture made up of aromatic alcohols, esters, ketones, and acids, as well as phenols, aliphatic aldehydes, and aliphatic acids. EAG responses to pure samples of all identified components were recorded, and many of these compounds were found to be quite active. Among the most stimulatory were guaiacol, methyl benzoate, and l-phenyl-1,2-propanedione. Also tested were six-carbon aliphatic aldehydes and alcohols which are components of the foliar tissue of most plants. Of these, 1-hexanol showed moderate activity, while the aldehydes and unsaturated alcohols were only weakly active.Lepidoptera: Sesiidae.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.  相似文献   

12.
POSS supported prolinamide-type catalysts were synthesized and used to catalyze asymmetric Aldol reactions between unmodified ketones and aldehydes. Immobilization of the prolinamide-type catalysts onto POSS resulted in good yields and improved diastereoselectivity as well as enantioselectivity. The POSS-supported catalysts were recycled simply by precipitation and filtration, and could be reused in five consecutive cycles without losing its effectiveness.  相似文献   

13.
The reactions of rubber with aldehydes have previously been studied in latex or in solutions and the reaction products formed by cyclization, condensation, or addition, have been reported. In the present study, solid-state reactions of rubber with aldehydes were carried out. It was found that crosslinked rubbers may be obtained by press curing in the presence of aldehydes with acidic catalysts. Polychloroprene and Hypalon especially undergo these reactions without a catalyst or with a small amount of catalyst. In the experiments using various aldehydes, some improvements in the properties of the crosslinked rubber were observed when aldehydes such as paraformaldehyde or α-polyoxymethylene were used. Some Lewis acids such as SnCl2·2H2O were found to be more effective catalysts than the above, and it was found that organic acids such as p-toluenesulfonic acid could also be used. The curing seemed to be an ionic reaction. The physical properties of the crosslinked rubber are similar to these of sulfur-cured rubbers.  相似文献   

14.
The first organocatalytic, stereoselective and direct aldol reaction of activated thioesters with aldehydes has been accomplished. The trichlorosilyl ketene thioacetal generated in situ by adding a tertiary amine to a trifluoroethyl thioester in the presence of tetrachlorosilane is activated by catalytic amounts of an enantiomerically pure biheteroaromatic phosphine oxide to react with different aldehydes, coordinated to as well as activated by the chiral cationic hypervalent silicon species. Starting from a variety of readily available thioesters, this Lewis acid‐mediated Lewis base‐catalyzed transformation allows the direct synthesis of syn‐β‐hydroxy thioesters in up to 95% ee.  相似文献   

15.
高纯乙腈的应用及其提纯与精制工艺   总被引:2,自引:0,他引:2  
白聪丽  张奔  罗艳 《山东化工》2010,39(3):22-27
介绍现阶段高纯乙腈的应用;以及粗乙腈提纯精制高纯乙腈时,其主要杂质氢氰酸、丙烯腈、醛酮、噁唑、烯丙醇和水的去除方法和相关原理;概述新型高纯乙腈精制工艺的研究现状并将其与传统精制工艺对比,展望我国乙腈精制工艺的开发方向。  相似文献   

16.
Summary The preparation of linolenaldehyde and of mixed aldehydes from highly unsaturated sources, such as menhaden oilvia the acyloin condensation, is described. Reduction of the acyloins and subsequent cleavage of the glycols gave over-all yields of 85 to 90% free aldehydes. The intermediates in the synthesis as well as the final products were analyzed in part by the novel method of thin-layer silicic acid chromatography. Presented at the 51st Annual Spring Meeting, American Oil Chemists’ Society, Dallas, Tex., April 4–6, 1960. This is a laboratory of the Division of Industrial Research, U. S. Fish and Wildlife Service, Department of the Interior.  相似文献   

17.
Labeled alk-1-enyl glyceryl ethers were used in conjunction with thin layer chromatography to study the liberation of aldehydes from alk-1-enyl glyceryl ethers by two acid hydrolysis procedures. Both methods gave similar results, but neither liberated the aldehydes quantitatively. Only 75–85% of the alk-1-enyl glyceryl ether radioactivity was liberated as free aldehydes. Several nonaldehyde products were detected and one appeared to be a cyclic acetal. Under contract with the U.S. Atomic Energy Commission.  相似文献   

18.
Tertiary and secondary alcohols were directly reduced by saccharides, such as glucose, fructose, and cellulose, as well as by plant leaves and mushrooms in supercritical water using one-pot single-step reaction. Catalytic hydrogenations of olefins were also performed well in supercritical water in the presence of the saccharides. Nascent hydrogen can be an origin for both reactions because it is generated in supercritical water by the water–gas shift reaction of CO derived from aldehydes as decomposition products of the saccharides. Thus, bulk biomasses can be used as hydrogen donors in one-pot single-step direct organic transformations in supercritical water.  相似文献   

19.
The cross‐aldol reaction between enolizable aldehydes and α‐ketophosphonates was achieved for the first time by using 9‐amino‐9‐deoxy‐epi‐quinine as the catalyst. β‐Formyl‐α‐hydroxyphosphonates were obtained in high to excellent enantioselectivities. The reaction works especially well with acetaldehyde, which is a tough substrate for organocatalyzed cross‐aldol reactions. The products were demonstrated to have anticancer activities.  相似文献   

20.
简述了杀菌剂的概念、种类及其在洗涤剂中的应用目的和作用菌种,重点介绍了卤系、氧系、醛类、酚类、季铵盐、胍类及中草药提取物等国内抗、抑菌洗涤剂常用杀菌剂的特点和应用现状,对各品类杀菌剂的发展前景进行了展望。  相似文献   

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