Mechanistic aspects of aminium salt-catalyzed Diels-Alder reactions: The substrate ionization step
摘要:
Substituent effects in the aminium salt catalyzed Diels-Alder reactions of 2,3-dimethyl-1,3-butadiene with a series of meta and para substituted beta-methylstyrenes are used to probe detailed mechanistic aspects of these reactions. Kinetic studies were carried out using two different aminium salt catalysts and also electrochemically, using anodic potentials corresponding to the oxidation potentials of the aminium salts. Substituent effects in the equilibrium oxidations of the styrene substrates to the corresponding cation radicals were also studied, via oxidation potential measurements. The results indicate rate determining one electron oxidation of the sytrenes to their cation radicals via an outer sphere electron transfer.
[EN] COMBINATION THERAPY USING A BETA 3 ADRENERGIC RECEPTOR AGONIST AND AN ANTIMUSCARINIC AGENT<br/>[FR] POLYTHÉRAPIE UTILISANT UN AGONISTE DES RÉCEPTEURS ADRÉNERGIQUES BÊTA-3 ET UN AGENT ANTIMUSCARINIQUE
申请人:MERCK SHARP & DOHME
公开号:WO2011043942A1
公开(公告)日:2011-04-14
Described herein is an improved method of treating overactive bladder, wherein the method comprises administering to a patient in need thereof a beta 3 adrenergic receptor agonist, an antimuscarinic agent, and an optional selective M2 antagonist. Such combination therapy provides improved efficacy and/or reduced side effects.
A tandem Aldol-Grob reaction of ketones with aromatic aldehydes
作者:George W. Kabalka、David Tejedor、Nan-Sheng Li、Rama R. Malladi、Sarah Trotman
DOI:10.1016/s0040-4020(98)00976-4
日期:1998.12
Aromatic aldehydes react with ketones to produce(E)-1-aryl-1-alkenes via a tandem Aldol-Grob cleavage reaction sequence. The reaction, initiated by boron trifluoride, also produces a carboxylic acid fragment.
Electro‐mediated PhotoRedox Catalysis for Selective C(sp
<sup>3</sup>
)–O Cleavages of Phosphinated Alcohols to Carbanions
作者:Xianhai Tian、Tobias A. Karl、Sebastian Reiter、Shahboz Yakubov、Regina Vivie‐Riedle、Burkhard König、Joshua P. Barham
DOI:10.1002/anie.202105895
日期:2021.9.13
As well as deoxygenations, olefinations are reported which are E-selective and can be made Z-selective in a tandem reduction/photosensitization process where both steps are photoelectrochemically promoted. Spectroscopy, computation, and catalyst structural variations reveal that our new naphthalene monoimide-type catalyst allows for an intimate dispersive precomplexation of its radical anion form with
Method for synthesizing (E)-Anethol and Related Compounds By Cross Coupling Reaction of Potassium alllyltrifluroborate and 4-bromoanisole and aryl halides
申请人:AL-MASUM Mohammad
公开号:US20120010298A1
公开(公告)日:2012-01-12
Methods of producing substituted and non-substituted beta-methyl styrene by a cross-coupling reaction are provided. The disclosure also provides for methods of preparing (E)-Anethol and related compounds by a cross coupling reaction of potassium allyltrifluoroborate and 4-bromoanisole and aryl halides. Compounds, compositions, and methods of treating disorders utilizing beta-methyl styrene are also provided.
to afford 1-propenylbenzenes. The reaction shows a unique substituenteffect that is highly dependent on the distance of substituents from the allylic moiety. Thus, the reactivity of substrates bearing a methyl group is ordered in para > meta > ortho, whereas it is entirely reversed as ortho > meta > para for methoxy and chloro substituents.