نتایج جستجو برای: fluorinated enones

تعداد نتایج: 4816  

Journal: :Chemical science 2011
Kerem E Ozboya Tomislav Rovis

Herein we report an enantioselective synthesis of complex cyclopentanones using aliphatic aldehydes and activated enones. With the combination of a chiral secondary amine and a chiral triazolium catalyst, high diastereoselectivity and excellent enantioselectivity can be achieved. We present evidence of a clear cooperative effect when these two catalysts are present simultaneously in the system.

Journal: :Chemical communications 2007
Sze-Wan Li Robert A Batey

Lewis acid catalyzed reaction of 2-furaldehyde and secondary amines results in the formation of 4,5-diaminocyclopent-2-enones exclusively as the trans diastereomers: computational studies support the stereochemistry of the adducts as arising from a thermal conrotatory pi4a electrocyclization of an initial ring-opened intermediate (a deprotonated Stenhouse salt).

Journal: :Chemical communications 2005
Chiara Monti Cesare Gennari Umberto Piarulli

A highly enantioselective rhodium-catalysed conjugate addition of phenylboronic acid to cyclic enones has been achieved using a dynamic library of chiral phosphorus ligands; the tropos/atropos nature of the ligands in the rhodium complex has been characterised via 31P-NMR.

Journal: :Molecules 2017
Cheng Dong Xing-Feng Bai Ji-Yuan Lv Yu-Ming Cui Jian Cao Zhan-Jiang Zheng Li-Wen Xu

It was found that 1,2-trifluoromethylation reactions of ketones, enones, and aldehydes were easily accomplished using the Prakash reagent in the presence of catalytic amounts of cesium carbonate, which represents an experimentally convenient, atom-economic process for this anionic trifluoromethylation of non-enolisable aldehydes and ketones.

Journal: :Chemical communications 2015
Bjarke S Donslund Alicia Monleón Jesper Larsen Lise Ibsen Karl Anker Jørgensen

The highly enantioselective dienamine-mediated formation of 5-bromo-6-(trifluoromethyl)-3,4-dihydro-2H-pyrans from α,β-unsaturated aldehydes and α-bromo-(trifluoromethyl)-enones employing a C2-symmetric aminocatalyst is described. The products are demonstrated to be applicable in coupling reactions directly onto the ring, thereby granting access to a broad scope of highly substituted 6-(trifluo...

Journal: :Organic & biomolecular chemistry 2016
A-L Lee

This review highlights the use of the oxidative boron Heck reaction in enantioselective Heck-type couplings. The enantioselective oxidative boron Heck reaction overcomes several limitations of the traditional Pd(0)-catalysed Heck coupling and has subsequently allowed for intermolecular couplings of challenging systems such as cyclic enones, acyclic alkenes, and even site selectively on remote a...

Journal: :Organic & biomolecular chemistry 2012
Taku Kitanosono Masaru Sakai Masaharu Ueno Shū Kobayashi

Asymmetric Michael reactions and enantioselective protonations between enones and thiols were catalyzed by a Sc(OTf)(3)-chiral 2,2'-bipyridine complex in water. The remarkable governing of the enantioselectivity for simple introduction of protons despite their abnormally high mobility in water may provide us with new synthetic opportunities as well as significant chemical advances.

Journal: :Chemical communications 2012
Yong-Kyun Sim Hyejeong Lee Jung-Woo Park Dong-Su Kim Chul-Ho Jun

A new method for regiocontrolled pyridine synthesis has been developed involving sequential Rh(I)-catalyzed chelation-assisted hydroacylation of alkynes with aldehydes followed by Rh(III)-promoted N-annulation of the resulting α,β-enones with another alkyne and NH(3).

Journal: :Organic & biomolecular chemistry 2006
Simon J Webb Kevin Greenaway Marzieh Bayati Laurent Trembleau

To probe the effect of lipid fluorination on the formation of lipid domains in phospholipid bilayers, several new fluorinated and non-fluorinated synthetic lipids were synthesised, and the extent of phase separation of these lipids from phospholipid bilayers of different compositions was determined. At membrane concentrations as low as 1% mol/mol, both fluorinated and non-fluorinated lipids wer...

Journal: :Chemical communications 2010
Fuping Dong Wanping Guo Sang-Wook Chu Chang-Sik Ha

Fluorinated polysilsesquioxane (FPSQ) hollow spheres with a large empty interior were synthesized in an aqueous medium by using (trifluoropropyl)trimethoxysilane as the sole precursor. The drug release applications of these spheres were demonstrated, and the materials have great potential as fluorinated drug release carriers.

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