Palladium-catalyzed synthesis of highly substituted endocyclic enol lactones via a three-component coupling reaction in an ionic liquid

[reaction: see text] A new, efficient ionic liquid based synthetic procedure was developed for the preparation of highly substituted endocyclic enol lactones via the carbonylation coupling reactions of alkynes and 1,3-diketones in ionic liquid. The reactions proceeded in excellent regioselectivity and in reasonably good yields. The catalyst system can be recycled five times with only modest loss of its catalytic activity.     

Ruthenium(II) Pyrazolyl-Pyridyl-Oxazolinyl Complex Catalysts for the Asymmetric Transfer Hydrogenation of Ketones

Lowering the ketone: Ru(II) complexes containing a chiral pyridyl-based 1H-pyrazolyl-oxazolinyl NNN ligand were synthesized and structurally characterized by X-ray crystallographic studies. These complex catalysts efficiently catalyzed the asymmetric transfer hydrogenation of ketones, reaching up to 99?%?ee for the desired products.     

二甲胺基尾式卟啉铁的轴向配位状态

利用UV、MCD、Raman、EPR、Mssbauer、循环伏安等手段,研究了新型尾式卟啉铁-氯化中位一[邻-(4-二甲胺基丁酰胺基)苯基]三苯基卟啉合铁配合物不同价态下的轴向配位状态和它与含N碱及小分子CO、NO的轴向加合性质。结果表明:尾式卟啉铁(Ⅲ)呈现五配位高自旋(S=5/2)状态:尾端叔胺N不能与中心离子铁(Ⅲ)配位,而可以与铁(Ⅱ)生成五配位低自旋配合物。     

Ruthenium(III) chloride catalyzed efficient synthesis of unsymmetrical diorganyl selenides via cleavage of dibenzyl and diphenyl diselenides in the presence of zinc

[equation: see text] An efficient one-pot route to unsymmetrical diorganyl selenides has been developed by ruthenium(III) chloride catalyzed reactions of dibenzyl or diphenyl diselenides with alkyl halides in the presence of zinc. Organic iodides, bromides, and activated chlorides underwent the reactions efficiently. Unreactive organic chlorides also underwent the same type of selenation with sodium bromide as the additive.     

Benzodithiophene‐based poly(aryleneethynylene)s: Synthesis,optical properties,and applications in organic solar cells

The synthesis and characterization of building block of ethynylene‐substituted benzo[1,2‐b:4,5‐b′]dithiophene (BDT), and its application in the construction of poly(aryleneethynylene)s (PAEs) are described in this article. Alkoxy‐substituted BDT and thiazolothiazole are selected as the other copolymerized units, and polymers of PEBBDT and PEBTTZ were synthesized by Pd‐catalyzed Sonogashira coupling reaction. These polymers showed intense interchain π–π interaction and deep HOMO levels (≤ ?5.50 eV). Bulk heterojunction solar cell fabricated using PEBBDT or PEBTTZ as electron donor and PC₆₁BM as acceptor display power conversion efficiency of 0.85 and 2.40%, respectively, under the illumination of AM1.5G, 100 mW cm^?2. This study shows good prospect for the application of PAEs‐type polymers in organic solar cell. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 208–215     

Efficient reductive selenation of aromatic aldehydes to symmetrical diselenides with Se/CO/H(2)O under atmospheric pressure

An efficient method for the synthesis of symmetrical diselenides is described. Reductive selenation of aromatic and heterocyclic aromatic aldehydes (ArCHO) with Se/CO/H(2)O in DMF afforded diselenides (ArCH(2)SeSeCH(2)Ar) in yields up to 94% under atmospheric pressure without use of a base.     

碘化四-(4-三甲胺苯基)卟啉钴配合物的合成和性质研究

合成了一种新的水溶性碘化四-(4-三甲胺苯基)卟啉钴(CoTAPP·I·6H₂O)的配合物,进行了元素分析和差热,热重分析、测定了它的可见、紫外光谱、红外光谱、激光拉曼光谱和ESR谱,并对合成条件和性质进行了一些探讨。     

Structures and relationship between the 119SnNMR chemical shifts and pKa of their parent acids in organotin (I∇) carboxylates

Ten di-n-butyltin(I∇) carboxylates [(ⁿBu₂Sn-OCOR′)₂O]₂ and ⁿBu₂Sn(OCOR′)₂ (R′ = CCl₃, CHCl₂, CH₂Cl, PhCH = CH, and 2,2,3,3-tetramethylcyclopropyl) were synthesized and characterized by IR, ¹H, ¹³C, ¹¹⁹Sn NMR spectroscopy and elemental analysis. Together with other series of organotin(I∇) carboxylates, their structural features were discussed. The relationship between the ¹¹⁹Sn NMR chemical shifts in the organotin(I∇) carboxylates [(ⁿBu₂SnOCOR′)₂O]₂, ⁿBu₂Sn(OCOR′)₂, ⁿBu₃SnOCOR′, Ph₃SnOCOR′ and the pK_a values of their parent acids R′COOH was studied. The results have shown that the log[-δ(¹¹⁹Sn)] of the same series of carboxylates is linearly related to the pK_a of R′COOH. It seems that the better is the linearity between the log[−δ(¹¹⁹Sn)] and the pK_a, the more analogous are the structures of the same series of carboxylates. © 1996 John Wiley & Sons, Inc.     

氢同位素双原子分子的解析势能函数

研究从重水中分离出T2 .首先,根据光谱常数导出氢同位素双原子分子Extended Rydberg的分析函数,基于同位素效应计算OT(X 2Пi)的光谱常数,有助导出三原子分子,如DTO 的解析势能函数.将这些Extended Rydberg解析势能函数用于氘交换分离氚的热力学与分子反应动力学研究.此外,由同位素位移极值得到当振动量子数vmax≈11.5,振动能级间隔△Ev(H2)≈△Ev(T2),若v△Ev(T2)和v>vmax时,△Ev(H2)<△Ev(T2).因而,温度较低时,平衡移向T2;温度较高时,平衡移向H2 .与文献结果相似 ,而导出方法不同.     

钯催化下吡唑与2,6-二溴吡啶的偶联反应

 在相对温和的反应条件以及PPh3和KOtBu存在的情况下,Pd(OAc)2催化吡唑与2,6-二溴吡啶(摩尔比1∶2.4)的偶联反应主要生成单吡唑基取代的2-溴-6-吡唑基吡啶. 在无Pd(OAc)2/PPh3存在的情况下,则主要生成双吡唑基取代的2,6-二吡唑基吡啶. Pd(OAc)2与2-溴-6-吡唑基吡啶反应生成的配合物中间体可能抑制了双吡唑基取代产物的生成,从而影响产物分布.