The Reduction of Sulfoxides and Active Halides with Cp2TiCl2/Sm System

Cp₂TiCl₂/Samarium system is used as a new reagent for reducing sulfoxides to sulfides, benzyl halides to bibenzyls and α-bromoketones to ketones respectively in good yields under mild and neutral conditions.     

Facile and Mild Reduction of Sulfoxides to Sulfides with TiCl4/Sm System

TiCl₄/Sm system reduces sulfoxides rapidly to the corresponding sulfides in good yields in THF at room temperature.     

Cp2TiCl2/BuiMgBr/THF体系还原二芳基二硒醚

有机硒化合物具有生物活性[14],将硒基团引入到有机分子的一般方法是使亲核性的硒金属盐与亲电试剂反应 .二芳基二硒醚是制备有机硒化合物的重要中间体 .当它被还原时转化为硒负离子 ,被卤素等氧化时转化为亲电的硒试剂 .还原二硒醚通常使用ＮａＢＨ4[5 ],最近报道一些新的方法 ,如使用水合肼 /甲醇钠体系[6 ],Ｓｍ/ＨｇＣｌ2 体系[7].本文报道Ｃｐ2 ＴｉＣｌ2 /ＢｕｉＭｇＢｒ/ＴＨＦ体系还原二芳基二硒醚 .1　结果与讨论Ｃｐ2 ＴｉＣｌ2 与ＢｕｉＭｇＢｒ反应产生的钛氢化物是一种强的还原剂[8].在室温下 ,钛氢化物很容易与二硒醚反应生成…     

Titanium-catalyzed hydrosilylation of olefins: A comparison study on Cp2TiCl2/Sm and Cp2TiCl2/LiAlH4 catalyst system

Hydrosilylation of olefins catalyzed by Cp₂TiCl₂/Sm (Cp?=?cyclopentadienyl) under solvent free conditions have been investigated. By using Cp₂TiCl₂/Sm as catalyst system, β-adducts and hydrogenation products were detected. Hydrosilylation of olefins catalyzed by Cp₂TiCl₂/LiAlH₄ under room temperature has also been studied. The influence of TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) on Cp₂TiCl₂/Sm and Cp₂TiCl₂/LiAlH₄, respectively, indicated that hydrosilylation of olefins catalyzed with Cp₂TiCl₂/Sm went through a free radical reaction pathway while a coordination mechanism was applied for Cp₂TiCl₂/LiAlH₄ catalyst system.     

Reduction of Azides to Amines With SmI2 or Cp2TiCl2-Sm System

Azides can be rapidly reduced to corresponding amines with SmI₂ (Method A) or Cp₂TiCl₂-Sm system (Method B) in good yields under mild conditions.     

二茂二氯化钛存在下炔烃的还原反应

研究了双取代乙炔在二茂二氯化钛存在下被异丁基溴化镁格氏试剂还原生成烯烃的过程. 结果表明, 二苯乙炔还原后几乎得到专一的Z-二苯乙烯, 但多数炔烃还原后主要产物为E式烯烃, Z,E异构体的比例与底物炔烃的性质及位阻有关. 本文还报导了以双取代乙炔为底物, 径钛氢化反应合成了9组烯烃异构体混合物, 并对其结构进行了分析鉴定.     

Cp2TiCl2/助催化剂体系催化异戊二烯齐聚反应的研究

过渡金属催化剂催化异戊二烯齐聚反应, 因其重要的应用背景及学术研究价值而受到人们的关注. 其中研究得最多的是镍催化体系, 采用不同的镍催化体系可以选择性地得到各种线性或环状的二聚物或齐聚物[1,2].     

Mild and Efficient Deoxygenation of Sulfoxides to Sulfides with Cp2TiCl2/Gallium System

The Cp₂TiCl₂/Ga system was found to be a new reagent for reducing a variety of sulfoxides to the corresponding sulfides in good to excellent yields under mild conditions.      

Reduction of Diaryldiselenides by System of Cp2TiCl2/ BuiMgBr/ THF and Its Application in Synthesis of Unsymmetrical Diaryl Selenides

Inorganicseleniumchemistry,diaryldiseIenidesareimportantintermediateduetotheirstabiIityaganistairandwater.Whentheyarereduced,thenucleophilicseIenoatescanbeobtained.TherehavebeenseveralmethodsforthereductionofdiselenidessuchasviaNaBH".SmI==.thereductionsystemofSe,H=OandCO',hydrazine-sodiummethanoIate'andSm/HgCl='.Inthispaper,wereportthereductionsystemofCp=TiCl,/Bu'MgBr/THFanditsapplicationinsynthesisofunsymmetricaldiarylselenides.TitanocenehydridelCp,TiH]'wasderivedfromthereactionof…     

Cp2TiCl2/i-BuMgBr还原断裂Se—Csp键反应研究

Cp₂TiCl₂/i-BuMgBr体系形成的钛氢化试剂与炔硒醚反应生成端炔与深蓝色钛硒化物, 后者在空气中被氧化为二醚, 与酰氯反应, 高产率地形成对应的硒代酯.     

The Reductive Desulfonylation of β-Ketosulfones with TiCl4/Sm System

β-Ketosulfones can be readily desulfonylated with TiCl₄/Sm system to give corresponding ketones in acceptable yields in THF under mild conditons.     

Lithium nitride reduction of Cp2TiCl2 and CpTiCl3: The synthesis of (Cp2TiCl2), Cp2TiCl2)n,Cp2Ti(CO)2 and chlorotetratitanium and nitridohexatitanium complexes

Stoichiometric reactions of Cp₂TiCl₂ or CpTiCl₃ with Li₃N in various molar ratios result in reduction to (Cp₂TiCl)₂, (CpTiCl₂)_n and (CpTiCl)₄ and provide useful synthetic routes. Further reduction produces hexanuclear nitrido titanium clusters, Cp₈Ti₆N and Cp₈Ti₆N₃, characterised from mass spectral evidence. The nitrido clusters react with HCl to form (Cp₂TiCl)₂ and Cp₂TiCl₂. (Cp₂TiCl₂ is also obtained by reaction with Me₃SiCl. Cp₂Ti(CO)₂ is formed by the reaction between Cp₂TiCl₂ and Li₃ N in THF in the presence of CO.     

Reductive Coupling of Aldimines Mediated with Samarium Catalyzed by Cp2TiCl2

Reductive coupling of aldimines into vicinal diamines mediated with samarium catalyzed by Cp₂TiCl₂ proceeds in refluxing THF with good yields.     

Novel Reduction of Arylsulfonyl Chlorides to Disulfides with Sm/NiCl2/KI System

Arylsulfonyl chlorides can be readily reduced to corresponding disulfides with Sm/NiCl₂/KI system in moderate to good yields at 60°C.     

PEG1000-DIL/甲苯温控两相体系中硝基芳烃的还原反应

研究了PEG1000-DIL/甲苯温控体系中硝基芳烃的还原反应.考察了催化加氢、水合肼/FeCl3.6H2O和水合肼/Fe5HO8.4H2O等3种还原体系,发现水合肼/Fe5HO8.4H2O在PEG1000-DIL/甲苯温控体系中具有很高的催化活性,将其用于12种硝基芳烃的还原反应,产率最高可达99%.该催化体系重复使用3次后产率无明显变化,用于卤代硝基苯类化合物的还原可以有效防止脱卤副反应的发生.     

Facile Reduction of Chalcones to Dihydrochalcones with NaBH4/Ni2+ System

Chalcones have been found to undergo facile reduction on treatment with sodium borohydride-nickel chloride system in dioxan-methanol medium to afford dihydrochalcones.     

Design Platform for Sustainable Catalysis with Radicals: Electrochemical Activation of Cp2TiCl2 for Catalysis Unveiled

The combination of synthesis, rotating ring-disk electrode (RRDE) and cyclic voltammetry (CV) measurements, and computational investigations with the aid of DFT methods shows how a thiourea, a squaramide, and a bissulfonamide as additives affect the E_qC_r equilibrium of Cp₂TiCl₂. We have, for the first time, provided quantitative data for the E_qC_r equilibrium and have determined the stoichiometry of adduct formation of [Cp₂Ti(III)Cl₂]⁻, [Cp₂Ti(III)Cl] and [Cp₂Ti(IV)Cl₂] and the additives. By studying the structures of the complexes formed by DFT methods, we have established the Gibbs energies and enthalpies of complex formation as well as the adduct structures. The results not only demonstrate the correctness of our use of the E_qC_r equilibrium as predictor for sustainable catalysis. They are also a design platform for the development of novel additives in particular for enantioselective catalysis.