Rhodium Acetate Dimer Immobilized in 1-Butyl-3-methylimidazolium Hexafluorophosphate Ionic Liquid: a Novel and Recyclable Catalytic System for the Cyclopropanation of Alkenes
作者:J. S. Yadav、B. V. S. Reddy、P. Narayana Reddy
DOI:10.1002/adsc.200303136
日期:2004.1
Alkenes undergo smooth cyclopropanation with ethyl diazoacetate using a catalytic amount of rhodium acetate dimer, Rh2(OAc)4, immobilized in the air- and moisture-stable 1-butyl-3-methylimidazolium hexafluorophosphate ionic liquid, [bmim]PF6, to afford cyclopropanecarboxylates in excellent yields with high trans-selectivity. The recovery of the catalyst is facilitated by the hydrophobic nature of [bmim]PF6
Binuclear Copper Complexes and Their Catalytic Evaluation
作者:Raj K. Das、Mithun Sarkar、S. M. Wahidur Rahaman、Henri Doucet、Jitendra K. Bera
DOI:10.1002/ejic.201101283
日期:2012.4
dichloromethane. The two copper atoms in complex 1 are bridged by two L 1 ligands in a trans disposition; the naphthyridine nitrogen atoms bridge two copper centers and the carbonyl oxygen atoms occupy sites trans to the Cu···Cu vector. The metal···metal distance is 2.4594(6) A. In contrast, in complex 2, each of the two L 2 ligands bind to the two copper atoms through one naphthyridine nitrogen, a deprotonated amide
The present invention relates to carboxylic acid aromatic 1,2-cyclopropylamides of general formula (I) as described and defined herein, to pharmaceutical compositions and combinations comprising said compounds and to the use of said compounds for manufacturing a pharmaceutical composition for the treatment or prophylaxis of a disease, in particular of neurogenic disorder, as a sole agent or in combination with other active ingredients.
Solvolysis of 1-[<i>trans</i>-2-(<i>m</i>- or<i>p</i>-Substituted Phenyl)cyclopropyl]-1-methylethyl<i>p</i>-Nitrobenzoates
作者:Yoshiaki Kusuyama
DOI:10.1246/bcsj.71.685
日期:1998.3
value of r indicates the presence of the allylic cation intermediate where much more charge develops at the benzylic carbon for the derivatives with electron-donating substituents than is the case for the cyclopropylmethyl cation intermediate. Thus the solvolysis reaction proceeds via two independent pathways: one has a cyclopropyl cation intermediate and the ...
研究了 1-[反式-2-(间或对取代苯基)环丙基]-1-甲基乙基对硝基苯甲酸酯在 80% 丙酮水溶液中的反应性和产物组成。对于反应性较低的取代基,如 m-Br、m-Cl 和 m-CF3,溶剂分解产物是相应的 2-(2-芳基环丙基)-2-丙醇,表明是环丙基甲基阳离子中间体。随着取代基给电子能力的增加,开环产物增加。Yukawa-Tsuno 方程对反应性的应用提供了 -1.43 的 ρ 值和 0.59 的 r 值,相关系数为 0.997。较大的 r 值表明存在烯丙基阳离子中间体,其中具有给电子取代基的衍生物在苄基碳上产生的电荷比环丙基甲基阳离子中间体多得多。因此,溶剂分解反应通过两种独立的途径进行:一种是环丙基阳离子中间体,另一种是...
Iron-Catalyzed Cyclopropanation with Glycine Ethyl Ester Hydrochloride in Water
作者:Bill Morandi、Amund Dolva、E. M. Carreira
DOI:10.1021/ol300688p
日期:2012.4.20
An iron-catalyzed cyclopropanation reaction of styrenes in aqueous media is disclosed that employs glycine ethyl ester hydrochloride in a tandem diazotization/cyclopropanation reaction. The products are accessed in good yields and good diastereoselectivity using readily available and inexpensive starting materials. Moreover, a wide range of transition metals may be used under these conditions, thus