نتایج جستجو برای: αβ unsaturated carbonyl compounds

تعداد نتایج: 252812  

Journal: :Chemical communications 2012
Depeng Zhao Lijuan Mao Linqing Wang Dongxu Yang Rui Wang

The catalytic asymmetric phospha-Michael reaction of dialkyl phosphine oxides with β,β-disubstituted α,β-unsaturated carbonyl compounds was achieved. The products bearing tetrasubstituted carbon stereocenters were obtained in high yields with excellent enantioselectivities (up to >99% ee).

Journal: :Organic & biomolecular chemistry 2012
Hua Cui Ying Li Songlin Zhang

Carbonyl compounds react with organozinc reagents in the presence of diphenyl phosphite to give the corresponding olefins. A variety of 1,3-dienes and unsaturated esters were obtained in moderate to excellent yields under mild conditions.

Journal: :Environmental Health Perspectives 1990
E Eder C Hoffman H Bastian C Deininger S Scheckenbach

alpha, beta-Unsaturated carbonyl compounds are important not only from a theoretical but also a practical standpoint. These ubiquitous compounds can interact with DNA through various mechanisms. The predominant interaction is the formation of cyclic 1,N2-deoxyguanosine adducts; 7,8-cyclic guanine adducts are also found. We have synthesized and characterized the stereoisomers of adducts formed b...

Journal: :Chemical reviews 2005
Chao-Jun Li

4.2.8. Reductive Coupling 3109 5. Reaction of Aromatic Compounds 3110 5.1. Electrophilic Substitutions 3110 5.2. Radical Substitution 3111 5.3. Oxidative Coupling 3111 5.4. Photochemical Reactions 3111 6. Reaction of Carbonyl Compounds 3111 6.1. Nucleophilic Additions 3111 6.1.1. Allylation 3111 6.1.2. Propargylation 3120 6.1.3. Benzylation 3121 6.1.4. Arylation/Vinylation 3121 6.1.5. Alkynylat...

2012
Urmila Berar

Chalcones are a class of α,β-unsaturated carbonyl compounds that form the central core for a variety of naturally occurring biologically active compounds. They exhibit tremendous potential to act as a pharmacological agent. Besides their various pharmacological activities, chalcones have been explored for different optical applications including second harmonic generation materials in non-linea...

Journal: :Journal of the American Chemical Society 2011
Tianning Diao Shannon S Stahl

α,β-Unsaturated carbonyl compounds are versatile intermediates in the synthesis of pharmaceuticals and biologically active compounds. Here, we report the discovery and application of Pd(DMSO)(2)(TFA)(2) as a catalyst for direct dehydrogenation of cyclohexanones and other cyclic ketones to the corresponding enones, using O(2) as the oxidant. The substrate scope includes heterocyclic ketones and ...

Journal: :Chemical communications 2014
Kazunari Nakajima Mai Kitagawa Yuya Ashida Yoshihiro Miyake Yoshiaki Nishibayashi

We have succeeded in the visible light-mediated synthetic use of α-aminoalkyl radicals derived from α-silyl secondary amines toward addition to α,β-unsaturated carbonyl compounds. The resulting γ-aminocarbonyl compounds are converted into γ-lactams and pyrroles in a one-pot process.

Journal: :Journal of the American Chemical Society 2003
Fujie Tanaka Rajeswari Thayumanavan Carlos F Barbas

We have developed a new spectroscopic system for detecting carbon-carbon bond formation by fluorescence to enhance high-throughput catalyst screening and rapid characterization of catalysts on a small scale. Fluorogenic substrates composed of a fluorophore possessing an amino group are readily prepared as amides of alpha,beta-unsaturated carbonyl compounds and generally exhibit low fluorescence...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید