cyclopentane/[PdCl(C3H5)]2 efficiently catalyses the Heck reaction of disubstituted alkenes such as methyl crotonate, ethyl cinnamate, methyl methacrylate or α-methylstyrene with a variety of aryl halides. In the presence of 1,2-disubstituted alkenes the stereoselectivities of the reactions strongly depend on the substituents of the alkenes. Selectivities up to 97% in favor of E-isomers can be obtained
顺式,顺式,顺式-1,2,3,4-四(二苯基膦甲基)环戊烷/ [PdCl(C 3 H 5)] 2有效催化巴豆酸甲酯,肉桂酸乙酯,甲基丙烯酸甲酯或α等二取代烯烃的Heck反应-甲基苯乙烯与各种芳基卤化物。在1,2-二取代的烯烃的存在下,反应的立体选择性强烈取决于烯烃的取代基。添加到巴豆酸甲酯中可以得到高达97%的选择性,有利于E-异构体。用1,1-二取代的烯烃获得甲基丙烯酸甲酯或α-甲基苯乙烯的产物混合物。
Palladium(II) Acetate Catalyzed Reductive Heck Reaction of Enones; A Practical Approach
作者:Subramaniyan Mannathan、Saeed Raoufmoghaddam、Joost N. H. Reek、Johannes G. de Vries、Adriaan J. Minnaard
DOI:10.1002/cctc.201500760
日期:2015.12
A surprisingly practical Pd(OAc)2 or Pd(TFA)2‐catalyzed reductive Heckreaction between aryl iodides and α,β‐unsaturated ketones is described using N,N‐diisopropylethylamine (DIPEA, Hünigs base) as the reductant. In general, 1 mol % of Pd(OAc)2 is sufficient to afford good yields using electron‐rich or halogen‐substituted aryl iodides. Electron‐deficient aryl iodides preferentially give homocoupling
Pd–NHC Catalyzed Conjugate Addition versus the Mizoroki–Heck Reaction
作者:Aditya L. Gottumukkala、Johannes G. de Vries、Adriaan J. Minnaard
DOI:10.1002/chem.201003643
日期:2011.3.7
Ace of base: A catalytic system is presented that, solely by choice of the base, selectively switches between conjugateaddition and the Mizoroki–Heckreaction of aryl halides with Michael acceptors (see scheme; R, R′=alkyl, aryl). For conjugateadditionreactions, this avoids the preparation and use of organometallics.
Silver sequestration of halides for the activation of Pd(OAc)
<sub>2</sub>
catalyzed Mizoroki‐Heck reaction of 1,1 and 1,2 ‐ Disubstituted alkenes
作者:Pronnoy G. Bangar、Priyanka R. Jawalkar、Swapnil R. Dumbre、Dharmaraj J. Patil、Suresh Iyer
DOI:10.1002/aoc.4159
日期:2018.3
A ligand free catalytic system consisting of Pd(OAc)2 (cat) and stoichiometric quantities of silver salts, AgOAc or AgBF4, exhibit high efficiency in the Mizoroki‐Heck arylation, transforming aryl iodides and 1,1 as well as 1,2disubstitutedalkenes into 1,1,2 – trisubstituted aryl alkenes in excellent yields in very short reaction times.
The reaction of β-substituted-α,β-enones and -enals with aryl halides in the presence of a palladium catalyst has been investigated. The outcome of the reaction was found to be greatly dependent on the nature of the added base. Tertiary amines tend to favour the formation of conjugate addition-type products while sodium bicarbonate or sodium acetate that of vinylic substitution products. Usually, the