Studies on the catalysis of the reaction of organotin phenoxides with bis(2,2,2‐trichloroethyl) azodicarboxylate by lithium perchlorate

Organotin phenoxides, which are distinctly more active than the corresponding phenols, react at room temperature with bis(2,2,2‐trichloroethyl) azodicarboxylate to produce para‐substituted phenolic hydrazides in high yields. Copyright © 2004 John Wiley & Sons, Ltd.     

Catalysis of reactions of allyltin compounds and organotin phenoxides by lithium perchlorate

The effect of increase of polarity of the solvent binary mixture methanol-benzene and acetonitrile-chloroform on the selectivity and the rate of metalloene reaction of different allyltin compounds with 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD), diethyl azodicarboxylate (DEAD) and singlet oxygen was studied. The more polar solvent favored the production of the M-ene product. Analogous comparative studies were carried out in Et₂O and 4 mol dm⁻³ solutions of LiClO₄ in diethyl ether. All studied reactions were strongly catalysed by LiClO₄. Physicochemical studies were carried out in purpose to explain the catalytic effect of LiClO₄ on the aforementioned reactions. In case of singlet oxygen and diethyl azodicarboxylate it was presumably a result of facilitation of the formation of the polar intermediate by the ionic medium. Whereas, in case of PTAD the mentioned previously effect could be associated with lowering its LUMO by association with lithium. The analogous catalytic effect of LiClO₄ was also observed for reactions of organotin phenoxides with DEAD and bis(trichloroethyl) azodicarboxylate leading to corresponding ring-aminated phenols in excellent yield, and with diethyl acetylenedicarboxylate giving a mixture of corresponding vinyl ethers and ring ethenylated phenols. Organotin phenoxides were distinctly more active than the corresponding phenols.     

Studies on the catalysis of the reaction of organotin phenoxides with diethyl azodicarboxylate by lithium perchlorate

Organotin phenoxides react at room temperature with diethyl azodicarboxylate in diethyl ether, in the presence of lithium perchlorate, give the corresponding ring-aminated phenols in excellent yield.     

Studies on the reaction of organotin phenoxides with ethyl propiolate catalysed by triethylamine and tin(IV) chloride

Different tributyltin phenoxides react at room temperature with ethyl propiolate in benzene, in the presence of tin(IV) chloride, triethylamine and their mixture to give the derivatives of 3‐phenoxyacrylic acid ethyl ester. Exceptionally, 3‐(2‐hydroxyphenyl)acrylic acid ethyl ester and 3‐(2‐hydroxy‐5‐methylphenyl)acrylic acid ethyl ester have been obtained from the reaction of tributylphenoxytin and tributyl(p‐tolyloxy)tin, respectively catalysed by SnCl₄, and they have been easily hydrolysed to coumarin and 6‐methylcoumarin. Copyright © 2007 John Wiley & Sons, Ltd.     

New optically active organotin compounds for heterogeneous bimetallic catalysis

Chiral tin(IV) derivatives with two or three chiral centers adjacent to the metal (−)-Ment₂SnMe₂, (−)-Ment₂SnPh₂, (−)-Ment₃ SnCl, (−)-Ment₃SnH; (−)-Ment = (1R, 2S, 5R)-1-chloro-5-methyl-2-isopropylcyclohexane, R₂Sn[CH(Me)(n-Hex)]₂ (R = Bu or Ph) have been prepared either by the coupling of methylmagnesium chloride with tin halides or by the reaction of lithium stannates with optically active (2-octyl)tosylate. The stereospecificity of both processes was remarkably high, leading to new optically pure organotin reagents which have been fully characterized.     

钯催化芳基溴代物和氨基乙醛缩二乙醇的偶联反应研究

以Pd2（dba）3／XantPhos为原位生成的催化剂,研究了以芳基溴代物与氨基乙醛缩二乙醇之间的偶联反应合成N-（2,2-二乙氧基乙基）芳胺的反应,考察了催化剂前体、配体以及催化剂前体与配体的用量对该反应的影响．实验结果表明,当以2．5％Pd2（dba）3作为催化剂前体,3．75％XantPhos作为配体,吸电子取代和给电子取代的芳基溴代物均可与氨基乙醛缩二乙醇发生C—N交叉偶联反应,高选择性的得到产物N-（2,2-二乙氧基乙基）芳胺,分离收率为73％-96％．     

十二水合硫酸铁铵催化合成己二酸二乙酯的研究

以十二水合硫酸铁胺为催化剂合成了己二酸二乙酯,确定了酯化优化条件。实验结果表明,催化剂的催化活性高,反应条件温和,方法简便,酯化率优良。     

Triphenylphosphine-catalysed one-pot synthesis of γ-butyrolactone derivatives and highly substituted enones via reaction of dimethyl acetylenedicarboxylate and aryl aldehydes

The reaction between dimethyl acetylenedicarboxylate and various aryl aldehydes in the presence of triphenylphosphine leads to unsaturated γ-butyrolactone derivatives and highly substituted enones in fairly good yields at room temperature.     

Neryl- and geranyltriethylammonium halides in the allylation of sodium diethyl malonate. The effect of the leaving group of the allylating reagent on the selectivity of the reaction

In the absence of catalysts,N-neryl-andN-geranyltriethylammonium halides can allylate sodium diethyl malonate to give terpene malonate derivatives. Using the above-mentioned ammonium salts, geranyl and neryl acetates, geranyl ethyl carbonate, and geranyl diethyl phosphate as examples, it has been shown that with Pd⁰ and Pd^II catalysts, the selectivity of the formation of neryl-, geranyl-, and linalylmalonates can be governed by varying the leaving group of the allylating agent.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 270–272, February, 1994.     

Reactions of salicyl N-tosylimines or salicylaldehydes with diethyl acetylenedicarboxylate for the synthesis of highly functionalized chromenes

Reactions of diethyl acetylenedicarboxylate with salicyl N-tosylimines or salicylaldehydes proceeded smoothly in the presence of DABCO or dimethylphenylphosphine under mild conditions to give the corresponding chromenes in excellent yields.     

One-pot, four-component reaction of isocyanides, dimethyl acetylenedicarboxylate, and cyclobutene-1,2-diones: a synthesis of novel spiroheterocycles

Isocyanides, dimethyl acetylenedicarboxylate, and cyclobutene-1,2-diones react in one-pot to afford novel spirocyclic compounds with double insertion of the isocyanide.     

固-液相转移催化羰基化合成丙二酸二乙酯

本文首次以四乙基碘化铵为固-液相转移催化剂, 在常温常压下对氯乙酸乙酯进行催化羰基化反应, 定量合成了丙二酸二乙酯, 并讨论了各种因素对反应收率的影响。     

2,4-二硝基酚与二氟溴甲基膦酸二乙酯反应的研究

酚在碱性条件下与卤代烃反应生成相应的芳香醚,是典型的亲核取代反应,对于2,4-二硝基酚和二氟溴甲基膦酸二乙酯在碱性条件下的反应,其实验过程包括室温中和,甲苯回流脱水和亲核取代等三步反应。对产物进行了提纯和一系列的表征,结果发现主要生成了一种酚醚化合物。     

The three component reaction involving isocyanides, dimethyl acetylenedicarboxylate and quinoneimides: a facile synthesis of spirofused γ-iminolactams

The three component reaction of the zwitterion generated from dimethyl acetylenedicarboxylate and isocyanides with various quinoneimides is described. The reaction afforded the corresponding γ-spiroiminolactams in good yields.     

Cycloaddition reaction of 2‐allenylindoles with diethyl acetylenedicarboxylate under thermal and high pressure conditions

The cycloaddition reaction of 2‐allenylindoles 2 with diethyl acetylenedicarboxylate 6 was undertaken under both thermal and high pressure reaction conditions, leading to carbazole derivatives 5 .     

Studies on the Catalysis of Ene Reactions by Lithium Perchlorate in Different Solvents

Abstract

The catalytic effect of lithium perchlorate on ene reaction of cis-cyclooctene with diethyl azodicarboxylate, 4-phenyl-1,2,4-triazoline-3,5-dione and the metallo-ene reaction of diallyldibutyltin with diethyl azodicarboxylate has been studied in different solvents like acetonitrile, acetone, diethyl ether, dimethylformamide and ethyl acetate.     

Ceric (IV) ammonium nitrate (CAN) mediated synthesis of pyrrole-2,3,4,5-tetracarboxylates by reaction of dimethyl acetylenedicarboxylate with an amine

A simple one-step method for efficient synthesis of pyrrole-2,3,4,5-tetracarboxylates by reaction of dimethyl acetylenedicarboxylate with an amine using ceric (IV) ammonium nitrate as one electron oxidant is described.     

Mechanism of the Kolbe-Schmitt reaction with lithium and sodium phenoxides

The mechanisms of the carboxylation reactions of lithium and sodium phenoxides are investigated by means of the DFT method with a CEP-31 + G(d) basis set. The introduction of diffusion functions does not affect the outcome of the calculations. As a consequence, the results of this investigation are in good agreement with the findings obtained by means of the LANL2DZ basis set. Lithium phenoxide yields only salicylic acid in the Kolbe-Schmitt reaction. The reaction of sodium phenoxide can proceed in the ortho and para positions, but the para-substituted product can be expected at a very low concentration in the reaction mixture. The deviation of lithium and sodium phenoxides from the mechanisms of carboxylations of other alkali metals is a consequence of the small ionic radii of lithium and sodium. The text was submitted by the authors in English.     

毛细管气相色谱法测定二乙基二硫的含量

采用毛细管气相色谱法(GC)测定了二乙基二硫的含量.结果表明,二乙基二硫含量在0.01⁰.4g/L范围内具有良好的线性关系,平均回收率为99.91%;该方法简便、准确、重复性好,可方便地用于二乙基二硫含量的测定.