微波辅助合成邻羟基苯丁酮

利用微波辅助,以丁酸苯酯为原料,经Fries重排制备了邻羟基苯丁酮.通过单因素实验考察了反应时间、催化剂用量及反应温度对收率的影响,正交实验确定了最优工艺条件.结果表明,当n(催化剂):n(丁酸苯酯)=1.6,反应温度120℃,反应时间8 min时,丁酸苯酯完全转化,邻羟基苯丁酮收率45.0%.     

氯化磷酸二苯酯的合成和结构表征

以苯酚、三氯氧磷为原料,以无水三氯化铝为催化剂合成了氯化磷酸二苯酯;采用正交试验研究了反应温度、反应时间、催化剂用量和原料配比对反应收率的影响,确定了最佳工艺条件;并利用红外光谱和核磁共振谱表征了产物的结构.结果表明,影响反应收率的几种因素的排序为:反应温度>原料配比>催化剂用量>反应时间;最佳反应条件为:温度70℃、反应时间15h、原料配比(n苯酚∶n三氯氧磷)2∶1、催化剂用量0.8g(相对于苯酚的质量分数为4.25%).与此同时,采用加水后处理方法可以提高产品收率和可操作性.     

Williamson反应合成2-月桂氧基-N,N-二甲基乙胺

采用Williamson合成方法,以N,N-二甲基乙醇胺(C4H11NO)、氯代十二烷(C12H25Cl)及固碱(KOH)为原料,环己烷为带水剂,合成了2-月桂氧基-N,N-二甲基乙胺(C16H35NO)。对影响醚化反应各因素:原料配比、反应温度、反应时间以及催化剂的种类进行了探讨。用气相色谱法分析了产物含量,并用FT-IR、GC-MS和元素分析表征了产物结构。实验结果表明最佳工艺条件为:n(C4H11NO)∶n(C12H25Cl)∶n(KOH)=1.7∶1.0∶0.6;醚化反应温度:100℃;醚化反应时间:6h;催化剂:PEG-400(5mol%KOH),在此条件下2-月桂氧基-N,N-二甲基乙胺收率可达84.4%。     

3-硝基-2-氨基苯甲酸的合成

以邻苯二甲酸酐为起始原料,经硝化、脱水、酰胺化、霍夫曼重排4步反应合成了3-硝基-2-氨基苯甲酸,总收率19%,其结构经1H NMR, IR和元素分析表征.探讨了酰胺化和霍夫曼重排反应条件对产率的影响.结果表明, n(脲素) ∶ n(3-硝基邻苯二甲酸酐)=2.0 ∶ 1.0,于50 ℃～60 ℃反应5 h～6 h,酰胺化反应收率85%～91%.n(NaClO) ∶ n(3-硝基-2-甲酰胺基苯甲酸)=1.2 ∶ 1.0,于60 ℃反应3 h,重排反应收率94%.     

环氧环戊烷的无溶剂合成工艺

以聚苯乙烯-二乙烯苯接枝磷钨酸季铵盐为三相相转移催化剂,以H2O2为氧化剂,KCl为助催化剂,研究了环戊烯(CPE)合成环氧环戊烷(CPEO)的无溶剂工艺。 讨论了催化剂和助催化剂用量、反应温度、反应时间、环戊烯与H2O2摩尔比对反应的影响。 确定了无溶剂环氧环戊烷合成反应的条件为(以0.056 mol H2O2计)：催化剂1.0 g、助催化剂0.025 g、反应温度40 ℃、反应时间5 h、n(CPE)∶n(H2O2)=2.1∶1.0。 CPEO的平均收率约为96%。 催化剂回收重复使用6次活性无明显降低。     

4-(二苯氨基)苯甲醛的合成工艺改进

以Al Cl3为催化剂,三苯氨(1)和原甲酸三乙酯(2)为原料,合成了4-(二苯氨基)苯甲醛(3),其结构经1H NMR和FT-IR确证。合成3的较佳工艺条件为:1 40 mmol,n(1)∶n(2)∶n(Al Cl3)=1∶5∶8,苯为溶剂,于30℃反应4 h,收率91%。     

La(OTf)_3催化合成1,3-二噁烷-4,6-二酮化合物的研究

研究了在La(OTf)3的催化条件下,以丙二酸和酮为原料,缩合反应合成了3种1,3-二噁烷-4,6-二酮化合物.考察了酸酮物质的量之比、反应温度、反应时间、催化剂用量及催化剂的稳定性等因素对反应的影响.确定了其最佳反应条件为:取0.1mol丙二酸,n(丙二酸)∶n(酮)=1.0∶1.1,催化剂用量为0.3mol%,反应温度30℃,反应时间为3.0h,在上述反应条件下,产品收率可达62.3%～77.5%.     

硝酸铁对水杨酸甲酯的硝化及位置选择性

用硝酸铁对水杨酸甲酯硝化合成了3-硝基水杨酸甲酯和5-硝基水杨酸甲酯。 考察了反应时间、反应物配比、反应溶液酸碱性对产物收率和位置选择性的影响。 得出较好的反应条件为：反应时间3 h,n(硝酸铁)∶n(水杨酸甲酯)=2∶3。 少量硝酸有利于硝基化反应,且优先生成5-硝基水杨酸甲酯,而碱性不利于硝基化反应,且优先生成3-硝基水杨酸甲酯。 用量化计算解释了硝化反应的位置选择性机理。     

醚化剂GTA的合成及在制备阳离子聚乙烯醇中的应用

以三甲胺(TMA)和环氧氯丙烷(EPIC)为原料,超声条件下合成了醚化剂失水甘油基三甲基氯化铵(GTA),研究了物料配比、反应温度、反应时间对产物收率的影响,确定GTA最优合成工艺条件:n(TMA)∶n(EPIC)=2∶1,反应温度20℃,反应时间4 h,此条件下产物收率72%。用该中间体在碱性条件下对聚乙烯醇进行改性,可制得季铵盐型阳离子聚乙烯醇膜材料,通过正交实验确定季铵盐型阳离子聚乙烯醇最优合成工艺条件:n(GTA)∶n(PVA)=2∶1,反应温度60~70℃,反应时间5 h,p H为10,终产物收率88%。     

环保增塑剂柠檬酸三(2-乙基)己酯的合成

以柠檬酸和2-乙基己醇为原料,用结晶硫酸高铈为催化剂合成环保增塑剂柠檬酸三(2-乙基)己酯,考察了反应温度、催化剂用量、醇酸摩尔比、反应时间等因素对反应结果的影响,对合成的产品进行了红外光谱分析。实验结果表明,硫酸高铈催化合成柠檬酸三(2-乙基)己酯的最佳反应条件为n(2-乙基已醇)∶n(柠檬酸)=3.60∶1,催化剂用量为柠檬酸质量的1.5%,反应时间为90 m in,反应温度为150℃~160℃,在最佳反应条件下,柠檬酸三(2-乙基)己酯收率在98%以上。     

Electrochemical study of 1,2-Naphthoquinone-4-sulphonate and 1,2-Naphthoquinone semicarbazone

Summary A study of the electrochemical characteristics of 1,2-naphthoquinone-4-sulphonate, sodium salt, and of the semicarbazone of 1,2-naphthoquinone (Naftazone) was carried out using d.c., a.c. and d.p. polarography and cyclic voltammetry. Changes in the waves as a function of concentration and pH indicate evidence of adsorption phenomena at the potential of the reduction wave. These techniques also indicate the formation of a mercury derivative in the case of Naftazone. The quantitative determination of these two compounds is possible by polarography. Limits of detection are 5×10^–6 and 5×10^–8 M, respectively.

---

Elektrochemische Untersuchung von 1,2-Naphthochinon-4-sulfonat und 1,2-Naphthochinon-semicarbazon

Zusammenfassung Die elektrochemischen Eigenschaften von 1,2-Naphthochinon-4-sulfonat und -semicarbazon (Naftazon) wurden mit Hilfe der Gleichstrom-, Wechselstrom und Differentialpuls-Polarographie sowie der cyclischen Voltammetrie untersucht. Veränderungen an den Stufen in Abhängigkeit von Konzentration und pH-Wert deuten auf Adsorptionsvorgänge beim Potential der Reduktionsstufe hin. Im Falle von Naftazon wurde die Bildung eines Quecksilberderivats nachgewiesen. Beide Substanzen können polarographisch mit Nachweisgrenzen von 5×10^–6 bzw. 5 × 10^–8 M bestimmt werden.

     

1,2-Dibromoethane and KI mediated α-acyloxylation of ketones with carboxylic acids

The 1,2-dibromoethane-and Kl-mediatedα-acyloxylation of ketones is reported in moderate to good yield without the use of transition metals and strong oxidants.Various acids are well tolerated with wide functional group compatibility.An 1,2-dibromoethane-and Kl-catalysed reaction mechanism is proposed based on the results of control experiments.     

Eine neue Synthese von Tetrachlordiphosphan sowie Untersuchungen zur 1,2-Addition an Cycloalkene

A New Synthesis of Tetrachlorodiphosphane and Investigations Concerning the 1,2-Addition to Cycloalkenes . The phosphorus subhalide P₂Cl₄ has been synthesized by co-condensation of PCl₃ and Cu vapour in 14% yield. The ³¹P-NMR chemical shift of P₂Cl₄ has the value of δ=155. P₂Cl₄ decomposes during several hours at 0°C in a N₂ atmosphere by a disproportionation process to yield PCl₃ and a yellow polymeric compound of the approximately composition (PCl)_x. P₂Cl₄ is flammable in air to give POCl₃ and (PCl)_x. Investigations regarding the addition of P₂Cl₄ to cyclooctyne, cyclohexene, and cyclohexa-1,4-diene has been carried out. Surprisingly, cyclooctyne does not react with P₂Cl₄ but cyclohexene as well as cyclohexa-1,4-diene undergo 1,2-addition to yield the trans-1,2-bis(dichlorophosphino) substituted carbonhydrides. By derivatization with Me₃Si—NMe₂ the corresponding trans-1,2-bis[bis(dimethylamino)phosphino] compounds are synthesized.     

Solvent Effect of DMSO-d6 on 1,2-Diols in 1H NMR

There is a classic experiential rule about 1,2-diol RCR^1 （OH） CR^1 （OH） R（ R^1 = H or methyl）, that is, the proton chemical shift of the α-R^1 group at the hydroxvl group in the all-isomer, in general, aPPears in a higher field with ca.     

Synthesis of novel functionally substituted pyridazines and oxazines

Acetone 1,3-di(phenylhydrazone) reacts with arylidenemalononitriles in the presence of piperidine to give the coressponding 3,3′-carbonylbispyridazine derivatives. Under the same reaction conditions dioxime reacts with arylidenemalononitriles to give the corresponding 3,3′-carbonylbis-1,2-oxazines. Dioxime reacts with primary aromatic amines and formalin in a molar ratio of 1:1:2 to give 1-arylidene-3,5-dihydroxyimino-piperidine-4-ones. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1223–1229, August, 2008.     

碱催化促进Ni-W/β分子筛催化剂氢解纤维素产1,2-丙二醇的研究

为提高纤维素催化氢解产醇类产物中1,2-丙二醇(1,2-PG)的收率,采用等体积浸渍法制备了以β分子筛为载体负载Ni和W的催化剂。结果表明,当7Ni-20W/β分子筛作为催化剂时,在240℃反应温度和6.0 MPa H_2的条件下反应30 min后,纤维素实现完全转化,1,2-PG和乙二醇(EG)产率分别达到19.3%和45.3%;不同于其他载体催化剂,β分子筛可以明显提高1,2-PG选择性。当不同碱催化剂加入到Ni-W/β分子筛催化剂反应体系后,可以进一步提高1,2-PG的选择性。尤其是当加入Ba(OH)_2后,1,2-丙二醇产率从19.3%提高了32.5%。为了探究碱催化剂在反应中的作用,以葡萄糖为底物进行了一系列的碱催化反应。结果表明,碱催化剂主要作用是有助于将葡萄糖异构化为果糖,从而促进纤维素转化为1,2-PG。催化剂在两次回收重复利用之后1,2-PG的收率只下降3.9%,乙二醇产率收率下降4.1%。     

The effect of the nature of the surfactant on the location of 6-R-2,2,4-trimethyl-1,2-dihydroquinolines in micelles

The locus of solubilization of 6-R-2,2,4-trimethyl-1,2-dihydroquinoline molecules (R=Me, OEt) in sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB) has been determined by comparing the UV spectra of micellar solutions of the dihydroquinolines and their solutions in solvents of various polarities. The parameterR _pv (defined as the ratio of the absorbance of the long-wave band maximum to that at the adjacent valley) decreases with an increase in the solvent polarity in the order:n-heptane > 2-propanol > ethanol > H₂O. In SDS micellar solutions,R _pv is close to the corresponding value in water and does not depend on [SDS]. In CTAB micellar solutions,R _pv is essentially greater than in water and increases with [CTAB]. Thus, the solubilized dihydroquinoline molecules in SDS micelles reside in the Stern layer, and in CTAB micelles they are located both in the interior of the micelle and in the Stern layer; in this case the micelle packing begins from the core.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 948–950, May, 1994.     

N-Cyanomethyl-β-chloroamines: a convenient source of aziridinium ions

N-Cyanomethyl-β-chloroamines smoothly react with a range of alcohols or amines to give regio- and stereoselectively 1,2-aminoethers or 1,2-diamines. The reaction proceeds through the formation of an intermediate aziridinium ion. The N-cyanomethyl group can then be cleaved easily.     

Die CuCl-katalysierte Reaktion von Trimethylsilyl(t-butyl)chlorphosphan mit Dimethylzirconocen: Ein Beispiel der Tandem-Katalyse

The CuCl-catalyzed Reaction of Trimethylsilyl(t-butyl)chlorophosphane with Dimethylzirconocene: An Example for Tandem Catalysis t-BuP(SiMe₃)Cl was prepared from t-BuP(SiMe₃)₂ and hexachloroethane and reacted in situ with Cp₂ZrMe₂ in the presence of catalytic amounts of copper(I) chloride yielding t-Bu(Me)P? P(Cl)t-Bu ( 1 ) (2 : 1 reaction) or t-Bu(Me)P? P · (Me)t-Bu ( 2 ) (1 : 1 reaction) and Cp₂ZrCl(Me). To understand the course of reaction, the reaction of dimethylzirconocene with CuCl and the decomposition of t-BuP(SiMe₃)Cl in the presence of CuCl and tetrachloroethene were studied. The results suggest that CuCl reacts with t-BuP(SiMe₃)Cl in the presence of C₂Cl₄ to give t-Bu(Cl)P? P(Cl)t-Bu ( 3 ); simultaneously, CuCl reacts with Cp₂ZrMe₂ with formation of methylcopper, which reacts with 3 to give 1 or 2 , respectively.     

Aminoalkohole, 2. Mitt.: Ein Verfahren zur Herstellung enantiomerenreiner pharmakologisch aktiver β-Aminoalkohole

Zusammenfassung Die Reduktion enantiomerenreiner O-MBF- bzw. O-MBE-geschützter Cyanhydrine mit LiAlH₄ führt unter Einhaltung definierter Reaktionsbedingungen zu den entsprechenden geschützten Aminoalkoholen, in denen der Anteil der durch Epimerisierung gebildeten Nebenprodukte kleiner als 3% ist. Die Abtrennung der unerwünschten Diastereomere erfolgt im Zuge der Reinigung der Produkte. Durch Schutzgruppenabspaltung mit Salzsäure/Methanol können die enantiomerenreinen Aminoalkohole erhalten werden. Die meist sehr guten Trennfaktoren der O-MBF- bzw. O-MBE-geschützten Verbindungen erlauben für viele Verbindungen sowohl im Cyanhydrin- als auch im Aminoalkoholstadium eine präparative Trennung und machen das Verfahren deshalb vielseitig verwendbar.

---

Aminoalcohols II: Preparation of enantiomerically pure pharmacologically active -aminoalcohols

Summary A synthesis of -aminoalcohols is described starting from racemic or enantiomerically pure -hydroxynitriles which were O-protected using enantiomerically pure acetal type protective groups. Reduction with lithium aluminium hydride yielded O-protected -aminoalcohols. Whenever diastereomeric O-protected cyanohydrins could not be separated, the mixture was reduced and the resulting O-protected aminoalcohols were separated. Removal of the protective group using hydrogen chloride and methanol yielded enantiomerically pure -aminoalcohols or their corresponding hydrochlorides.

Herrn Prof. Dr.F. Eiden zum 70. Geburtstag gewidmet