两相催化体系中双子表面活性剂对1-十二烯氢甲酰化反应的助催化作用

合成了几种具有刚性连接基团的双子表面活性剂,研究了它们在Rh-TPPTS体系中催化长链烯烃氢甲酰化反应中的助催化作用.结果表明,在水/有机两相催化体系中,新型双子表面活性剂的助催化作用比单链表面活性剂CTAB更好,在较低的表面活性剂浓度下能得到较高的反应转化率.这归因于此类表面活性剂有较低的cmc,降低界面张力的能力和对1-十二烯的增溶能力比CTAB更强.     

两相催化体系中双子表面活性剂对1-十二烯氢甲酰化反应的促进作用

报道了水溶性铑膦配合物组成的复合催化体系催化1-十二烯氢甲酰化反应中,双子表面活性剂[二溴化-(N,N,N′,N′-四甲基)-N,N′-二(十六烷基)-乙二铵]形成胶束的助催化作用.结果表明,在水/有机两相中,双子表面活性剂比单链表面活性剂CTAB具有更好加速催化反应的作用,并使烯烃氢甲酰化的区域选择性显著提高.这归因于双子表面活性剂有较低的cmc,可形成更加紧密规整的胶束结构,有利于增溶在胶束中的烯烃与铑催化剂配位和生成正构醛.     

新型水溶性膦铑络合物催化烯烃的氢甲酰化反应研究

新型水溶性膦铑络合物催化烯烃的氢甲酰化反应研究燕远勇，左焕培，金子林（大连理工大学化工学院，大连１１６０１２）关键词烯烃，水溶性膦铑络合催化剂，氢甲酰化，醛．１．前言为克服催化剂的流失和与反应产物的分离困难，近年来均相催化的一个重要进展是开发了以磺化...     

Structures of the tricyclododecenes prepared by the catalytical intramolecular cyclisation of 1,5,9-cyclododecatriene

The internal cyclisation of 1,5,9-cyclododecatriene, induced by a catalytical amount of Cp₂TiCl₂-LAHδ, leads to a mixture of cis, anti, cis-tricyclo[7.3.0.0^2,6]-7-dodecene (1), cis,syn,trans-tricyclo[7.3.0.0^2,6]-7-dodecene (2), trans,syn-tricyelop[7.3.0.0^2,6]-6-dodecene (3) and 5,6,7,8,9,10-hexahydrobenzocyclooctene (4). The structures of the main products were determined from the spectra of a number of derivatives taking into account symmetry properties and configurational flexibility.     

Modified cobalt(II) acetylacetonate complexes as catalysts for Negishi-type coupling reactions: influence of ligand electronic properties on catalyst activity

Four known electronically diverse cobalt(II) acetylacetonate derivatives were synthesized by replacement of the acetylacetonate methyl groups with combinations of tert-butyl, ethoxy, and trifluoromethyl groups in order to study the effect of catalyst electronic properties on the reaction rate and product yield of the cobalt-catalyzed reaction between haloalkenes and butylzinc iodide. Infrared spectroscopy of these compounds showed an increase in the CO stretching frequency as the ligand substituents became more electron withdrawing. These compounds, in addition to cobalt(II) acetylacetonate itself, were evaluated as catalysts for the coupling reaction between (E)-1-iodo-1-octene and butylzinc iodide to form (E)-5-dodecene. Faster reaction rates were observed and higher yields of 5-dodecene were produced when catalysts containing electron-donating ligands were employed. Side reactions, including the homocoupling of 1-iodo-1-octene to produce 7,9-hexadecadiene, were also observed under the reported reaction conditions. The rate of side-product formation was more competitive with the rate of the cross-coupling reaction when slower, electron-deficient catalysts were employed.     

Photoassisted Methoxycarbonylation of Straight-Chain Terminal Olefins under Ambient Conditions

Muchattentionhasrecentlybeenpaidtophotoassisted0rganicsynthesiswithhighyieldsandselectivitiesl'2.Theincreasingnumberofpapershaveshownthatthereisasubstantialinterestintheapplication0fph0t0chemicaltechniquestoh0mogeneouscatalysis.Well-knownexamples,whichshowthatlightcaninitiateandacceleratecatalyticreacti0ns,includephotocatalyzed0lefinisomerization',methoxycarb0nylati0n',andfunctiona-lizationoftheC-Hbondofalkanes5'6.Itiskn0wnthatmeth0xycarb0nylationofolefinsisanimp0rtantchemicalprocess,butitsap…     

Cobalt-catalyzed dimerization of alpha-olefins to give linear alpha-olefin products

[Cp*P(OMe)3CoCH2CH3]+ [BarF]-, generated by the addition of HBArF to Cp*P(OMe)3Co(ethene), catalyzes the oligomerization of 1-hexene to give dimers and trimers. When a deficit of the acid is used, linear alpha-olefin dimers are produced at the expense of trimeric products: e.g., 1-butene, 1-hexene, and 1-octene give 1-octene, 1-dodecene, and 1-hexadecene, respectively.     

Chemical composition of essential oil of Senecio coincyi, an endemic species of the Central Iberian Peninsula

The essential oil has been studied of leaves of Senecio coincyi Rouy, an endemic species of Spain restricted to a very small area of the Central Iberian Peninsula. Samples from five locations were obtained by hydrodistillation and extraction and analysed by gas chromatography-mass spectrometry. The main compound was 1-tridecene (28.1 +/- 8.5%). The presence of unsaturated hydrocarbons (1-undecene, 1-dodecene and 1-tridecene) seems to indicate a chemotaxonomic relationship between Senecio coincyi and S. congestus.     

A New Synthesis of 2-(6-Methoxycarbonylhexyl)-Cyclopent-2-EN-1-One Using α-Silylallyl Sulphide

Acylation of the α-trimethylsilylallyl phenyl sulphide (2). by reaction with the acid chloride (3), catalyzed by aluminium chloride in CH₂Cl₂ at ?78°C, gave methyl 9-oxo-12-phenylthio-11-dodecene (4). Hydrolysis of (4) followed by aldol condensation gave 2-(6-methoxycarbonylhexyl)-cyclopent-2-en-1-one (6).     

洞状咪唑环番的合成和晶体结构

由1,3,5-三甲基-2,4,6-三(咪唑甲基)苯与1,3,5-三(溴甲基)苯直接季铵化反应高产率地合成了洞状咪唑环番3(C30H33N63+*Br－3*3H2 O), 对目标物的分子和晶体结构进行了表征. 该晶体属单斜晶系, 空间群为P21, 晶胞参数： a=0.863 4(2) nm, b=0.817 0(4) nm, c=1.088 4(2) nm, β=112.03(1)°, V=\{1.582 8(6)\} nm3, Z=2, R=0.033 6, F(000)= 780． 溴离子与水分子形成氢键． 分子和晶体结构表明化合物具有选择性识别一些阴离子或中性分子的适宜结构．     

One-pot Synthesis of Lewis Acidic Ionic Liquids for Friedel-Crafts Alkylation

Lewis acidic ionic liquids have been receiving extensive interest as green substitute for H2SO4, HF and AlCl3 catalysts in chemical processes1. In view of the principles of green chemistry2, ionic liquids themselves are highly expected to be obtained via …     

A comparative study of the catalytic behavior of SBA-15 supported heteropoly acid H3PW12O40 and H-Y catalysts in the alkylation of benzene with 1-dodecene

The SBA-15 supported 12-phosphotungstic acid catalyst exhibits much higher catalytic activity, selectivity and stability than H-Y zeolite in the alkylation of benzene with 1-dodecene at reaction temperature of 80°C, with the 1-dodecene conversion of nearly 90%, 2-phenyldodecane selectivity of nearly 40%, and monoalkylbenzene selectivity of 100%. This revised version was published online in June 2006 with corrections to the Cover Date.     

Highly active and stable immobilized aluminium chloride catalyst for alkylation of benzene with 1-dodecene

Summary An AlCl₃ catalyst immobilized on<span lang=EN-US style='font-family:Symbol;mso-bidi-font-family: Symbol;mso-ansi-language:EN-US'>g-Al₂O₃with meso- and macro-pore bimodal structure was prepared and studied in the alkylation of benzene with 1-dodecene in a suspension bed reactor. The catalyst exhibited high activity, selectivity and stability during 1000 h running, with a 1-dodecene conversion of more than 95%, monoalkylbenzene selectivity of 92%, and 2-phenyldodecane (2-Ph) selectivity of nearly 42%.</o:p>     

Homogeneous catalytic aminocarbonylation of 1-iodo-1-dodecene. The facile synthesis of odd-number carboxamides via palladium-catalysed aminocarbonylation

Various amine nucleophiles including glycine methyl ester were used in the palladium-catalysed aminocarbonylation of (E)- and (Z)-1-iodo-1-dodecene. The substrates were synthesised from 1-dodecanal via the corresponding hydrazone, which was treated with iodine in the presence of tetramethylguanidine. The homogeneous catalytic aminocarbonylation resulted in the corresponding odd-number carboxamides in moderate to good yields. The reaction was accompanied by the formation of some carboxamides with triple bonds in the 2-position. The latter products were formed in relatively high yields with secondary amines such as piperidine and morpholine and were isolated as pure compounds.     

Hydroaminomethylation of 1-Dodecene Catalyzed by Water-soluble Rhodium Complex

The hydroaminomethylation of 1-dodecene catalyzed by water soluble rhodium complex RhCI(CO)(TPPTS)2 in the presence ofsurfactant CTAB was investigated. High reactivity and selectivity for tertiary amine were achieved under relatively mild conditions.     

Metal ions exchanged montmorillonite as catalyst for alkylation of benzene with 1-dodecene

Summary About 8.5% of benzene was alkylated with 1-dodecene in the presence of Na⁺-montmorillonite. When the reaction was carried out with montmorillonite exchanged with Mn²⁺, Cu²⁺, Ni²⁺, Zn²⁺ and Fe²⁺ ions as catalyst (M²⁺/mont.), 91 to 95% of 1-dodecene was remarkably converted to a mixture of linear monoalkylbenzenes.     

Highly stereoselective synthesis of (E)- and (Z)-alpha-fluoro-alpha,beta-unsaturated esters and (E)- and (Z)-alpha-fluoro-alpha,beta-unsaturated amides from 1-bromo-1-fluoroalkenes via palladium-catalyzed carbonylation reactions

The highly stereoselective synthesis of (E)- and (Z)-alpha-fluoro-alpha,beta-unsaturated esters and (E)- and (Z)-alpha-fluoro-alpha,beta-unsaturated amides is described. 1-Bromo-1-fluoroalkenes (E/Z approximately 1:1), which are readily available starting materials, have been found to isomerize to high E/Z ratios after storage at -20 degrees C for 1 week or by photolysis at 254 nm. Since the (E)-isomers have been found to react faster than the corresponding (Z)-isomers at room temperature in Pd(0)-catalyzed reactions, the palladium-catalyzed carboalkoxylation of high E/Z 1-bromo-1-fluoroalkenes lead to a high Z/E (Z/E >/= 98:2) ratio of the alpha-fluoro-alpha,beta-unsaturated esters. When 1-bromo-1-fluoroalkenes (E/Z approximately 1:1) were reacted with HCOOH/NBu(3)/Pd(II)/DMF, the (E)-isomer was selectively reduced, and the remaining (Z)-1-bromo-1-fluoroalkenes were recovered in essentially pure isomeric form. The resulting mixture of (Z)-1-bromo-1-fluoroalkenes and the reduced products underwent similar palladium-catalyzed carboalkoxylation reactions at 70 degrees C, and the (E)-alpha-fluoro-alpha,beta-unsaturated esters were stereospecifically obtained. This methodology was also successfully applied for the stereospecific synthesis of (Z)- and (E)-alpha-fluoro-alpha,beta-unsaturated amides: the palladium-catalyzed carboamidation reaction of high E/Z and (Z)-1-bromo-1-fluoroalkenes lead to pure (Z)- and (E)-alpha-fluoro-alpha,beta-unsaturated amides, respectively.     

A New Methodology for Synthesis of 1,2-Epoxy Alkane with the Linear Aliphatic Olefins in Presence of Molecular Oxygen

The linear aliphatic olefins, such as 1-octene, 1-decene, 1-dodecene and 1-tetradecene, were effectively epoxidized with molecular oxygen catalyzed by the amino acid Schiffbase manganese complex (Sal-Phe-Mn). The products of the reaction was 1, 2-epoxy alkane     

[Bmim]Br-AlCl3催化苯与1-十二烯烃烷基化反应机理的研究

利用同位素取代法考察了[Bmim]Br-AlCl3催化苯与1-十二烯烃烷基化反应机理. 首先进行了[Bmim]Br-AlCl3催化氘代苯与1-十二烯烃的反应, 通过GC-MS及NMR分析产物十二烷基苯同分异构体的结构, 验证了氘原子与产物侧链1-位碳相连的结论. 示踪氘原子推导了烷基化反应机理, 结果表明: [Bmim]Br-AlCl3催化苯与长链烯烃的烷基化反应是由[Al2Cl6Br]－发生平衡移动, 生成Lewis酸AlCl3引发的; AlCl3吸电子作用使1-十二烯烃的π电子向1-碳转移, 在烯烃的2-碳上形成正电荷中心, 碳正离子与苯发生亲电反应生成不稳定的σ络合物, 与σ络合物环上的σ-C相连的D＋转移到负电的侧链1-C上形成C—D键, AlCl3离去, 生成产物2-十二烷基苯. Lewis酸催化机理为离子液体催化苯与长链烯烃的反应中, 2-十二烷基苯选择性高于H质子催化产物提供了理论依据.     

Kinetik und stereochemischer Verlauf der thermischen Umlagerung der vier stereoisomeren Propenyl-(but-2′-enyl)-äther

The gas-phase rearrangement of (1Z, 2′E)-, (1Z, 2′Z)-, (1E, 2′E)-, and (1E, 2′Z)- propenyl but-2′-enyl ether (Z, E)-, (Z, Z)-, (E, E)-, and (E, Z)-1) into erythro- and threo-2, 3-dimethyl-pent-4-en-al (erythro- and threo-2) was investigated over a temperature range from 142,5° to 190,0° at 20–35 Torr (for kinetic data and activation parameters see table 2). All four stereoisomeric ethers 1 rearrange preferentially via a chair-like transition state C into the aldehydes 2 (ΔΔG^≠ (160°) = 2,5–2,7 kcal/mol for B – C (B = boat-like transition state). The relative rates (k_rel) for (Z, Z)-1, (Z, E)-1, (E,Z)-1, and (E,E)-1 at 160° are 1,0, 2,9, 4,3 and 9,0 respectively (see table 5). Taking into account the relative enthalpies of the ethers 1 and the steric interaction in the C transition state of the ethers 1 (see table 6), k_rel values can be estimated. They are in good agreement with those observed (see table 5).