Trifluoromethylation of carbonyl compounds with sodium trifluoroacetate

In the presence of copper(I) iodide as catalyst, a variety of carbonyl compounds, such as aldehydes, ketones and acid anhydrous, could be trifluoromethylated with sodium trifluoroacetate to give the corresponding alcohols in moderate to high yields, and a possible mechanism was proposed to explain the roles of catalyst and solvent in the reaction system.     

Synthesis and Crystal Structure of Mn(phen)(CF_3COO)(H_2O)_3·NO_3

1 INTRODUCTION The manganese(II) ion is a biologically essential element. Knowledge of its importance is increasing as more and more enzymes are found to contain manganese ions at the active center[1, 2]. The X-ray crystallographic structures of a consi…     

Synthesis of 4H-Pyrrolo[2,1-C][1,4]benzothiazines and 3-(Methylthio)oxindoles

The Pummerer reaction was carried out with α-acylsulfides and phenyl iodosyl bis(trifluoroacetate) instead of α-acylsulfoxides to prepare 4H-pyrrolo[2,1-c][1,4]benzothiazines and 3-(methyIthio)oxindoles.     

Facile protection of carbonyl compounds as oxathiolanes and transoxathioacetalization of oxyacetals promoted by iron(III) trifluoroacetate or trifluoromethanesulfonate as chemoselective and recyclable catalysts

Oxathioacetalization of carbonyl compounds and transoxathioacetalization of O,O-acetals/ketals are reported under nearly neutral conditions promoted by iron(III) trifluoroacetate [Fe(CF₃CO₂)₃] or trifluoromethanesulfonate [Fe(CF₃SO₃)₃] as recyclable and highly efficient Lewis acid catalysts.     

Improved Procedure for the Synthesis of DAMGO

A short and straightforward synthesis of DAMGO is described.     

有机化学创新设计性实验“甲基化反应”的改进*

结合科研成果及实验教学经验,对有机化学实验中传统的甲基化反应实验进行改进。教材中涉及的传统甲基化试剂具有毒性大等缺点,不利于实验教学的实施。因此,提出使用三氟乙酸甲酯取代传统甲基化试剂,应用于本科有机化学实验教学中,加强学生对甲基化反应理论知识的理解。本实验结合新颖的科研内容,引入科研实验的设计思路,不仅有利于学生更好地掌握理论知识,而且有利于激发学生对科学研究的兴趣,提高学生的综合素养。     

一种提高铂电催化氧化甲酸性能的简单方法

在离子液体1-乙基咪唑三氟乙酸盐(HElmTfa)中,采用循环伏安法在铂电极表面修饰聚吡咯(PPY),制得PPy-HEImTfa/Pt,并研究了其对甲酸的电催化氧化性能.与相同条件下的铂基底电极相比,PPy-HEImTfa/Pt对甲酸的电催化氧化性能有很大的提高.原位红外光谱表明,PPy-HElmTfa能降低中间体CO等对铂电极的毒化作用,促进甲酸直接氧化生成CO_2.     

离子色谱法-间接紫外检测离子液体中三种含氟酸根阴离子

建立了离子色谱-间接紫外检测法同时分析离子液体中的三氟乙酸根(CF3COO-)、四氟硼酸根(BF4-)和三氟甲烷磺酸根(CF3SO3-)的方法。用Shodex IC NI-424阴离子交换柱作为分离柱,探讨了影响上述三种离子保留和检测的因素及其保留规律。最终选用色谱条件为:以1.75 mmol·L-1邻苯二甲酸-1.68 mmol·L-1三(羟甲基)氨基甲烷为淋洗液,柱温45℃,流速1.0 m L·min-1,UV检测波长设定在265 nm。在此条件下,可实现上述三种阴离子的同时分析,且色谱峰形良好。所测阴离子的检出限(S/N=3)为0.39~1.57 mg·L-1,保留时间和峰面积的相对标准偏差(n=5)均在1%以下。将此方法应用于测定离子液体中的三氟乙酸根、四氟硼酸根及三氟甲烷磺酸根,加标回收率为99%~102%。该方法简单、准确、可靠,具有较好的实用性。     

SO42-促进的中孔含锆分子筛催化合成乙酸松油酯的研究

合成了中孔含锆分子筛Zr-MCM-41，用H2SO4对Zr-MCM-41进行修饰，得到SO4^2-促进的中孔含锆分子筛SO4^2-／Zr-MCM-41．通过XRD、FT—IR表征了其结构．结果表明：Zr—MCM-41和SO4^2-／Zr—MCM-41具有中孔分子筛的特征结构、良好的长程有序性和结晶度；SO4^2-已进入Zr—MCM-41骨架内部，并与骨架原子形成了化学键，从而产生强酸中心，将SO4^2-／Zr—MCM-41用于催化合成乙酸松油酯，考察了催化剂的种类、反应温度、反应时间及反应物配比对松油醇酯化反应结果的影响．     

Quantum-chemical study of the structure of copper(I) acetate and trifluoroacetate oligomers

The results of B3LYP quantum-chemical calculations of the equilibrium structures of [(CX₃COOCu)₂]₃, [(CX₃COOCu)₂]₂, and (CX₃COOCu)₂ oligomers (X = H, F) using the cc-pVTZ correlation-consistent basis for C, O, and F atoms and the Stuttgart 1997 RSC basis and relativistic effective core potential for Cu(I) atoms are presented. The differences in the structures of the free dimer and dimer units in oligomers were studied. The hexamer structure was chosen as the model of a fragment of the crystalline phase. Good agreement was obtained between the experimental and calculated differences between the geometrical parameters of the structures in the “gas phase-crystal” and “acetate-trifluoroacetate” series. Based on the calculated data, the increase in the Cu(I)-Cu(I) bond length in the silver acetate crystal compared with the gas phase can be explained by the effect of the neighboring dimer units of the polymer ribbon, while the increase in the Cu(I)-Cu(I) bond length in gaseous trifluoroacetate compared with acetate, by the acceptor effect of fluorine atoms.