نتایج جستجو برای: cycloalkenes
تعداد نتایج: 90 فیلتر نتایج به سال:
Hypervalent iodine reagents constitute a powerful tool in modern synthetic organic chemistry, promoting several important reactions. One such reaction is the ring contraction of cycloalkenes and cycloalkanones promoted by iodine(III) compounds, such as iodobenzene diacetate, iodosylbenzene, iodotoluene difluoride, and [hydroxy(tosyloxy)- iodo]benzene (Koser' s reagent). This review covers all t...
A rhodium-catalyzed dehydrogenative borylation of cyclic alkenes is described. This reaction provides direct access to cyclic 1-alkenylboronic acid pinacol esters, useful intermediates in organic synthesis. Suzuki-Miyaura cross-coupling applications are also presented.
[figure: see text] The formation of the trisubstituted cycloalkene 7 by RCM of diene 5 proceeds via the acyclic dimer 6, thus demonstrating the ready reversibility of olefin metathesis if catalyzed by "second generation" ruthenium carbene complexes such as 2-4. When applied to acrylate 11, these catalysts trigger a cyclooligomerization process that evolves with time and serves as key step en ro...
Asymmetric coupling proceeds efficiently between propargylic acetates, cycloalkenes and electron-rich heteroarenes including indoles, pyrroles, activated furans thiophenes. 2,3-Disubstituted tetrahydrofurans pyrrolidines are produced in trans configuration excellent enantiomeric ratios. The reaction via Wacker-type attack of nucleophilic on alkenes by allenyl PdII species.
The first examples of palladium-catalyzed oxidative amination of unactivated alkyl olefins have been identified. To be successful, these reactions must be conducted under cocatalyst-free conditions that involve direct dioxygen-coupled turnover of the palladium catalyst. The oxidative amination products of norbornene and other cyclic alkenes implicate a cis-aminopalladation mechanism.
The potential energy surfaces for ring-closing metathesis reactions of a series of simple α,ω-dienes which lead to 5-10 membered ring products, have been explored using density functional theory methods. We have investigated both the conformational aspects of the hydrocarbon chain during the course of the reactions, as well as the stationary structures on the corresponding potential energy surf...
The Aerodyne aerosol mass spectrometer (AMS) was used to characterize physical and chemical properties of secondary organic aerosol (SOA) formed during ozonolysis of cycloalkenes and biogenic hydrocarbons and photo-oxidation of m-xylene. Comparison of mass and volume distributions from the AMS and differential mobility analyzers yielded estimates of "effective" density of the SOA in the range o...
The total synthesis of (+)-nakadomarin A is described. A three-component cycloaddition of a hydroxylamine, aldehyde, and cyclopropane to form a highly functionalized tetrahydro-1,2-oxazine serves as the foundation for this synthesis. The resulting oxazine is formed as a single diastereomer with the absolute configuration being dictated by the chirality of the cyclopropane. Other key steps inclu...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید