Studies toward the Stereoselective Synthesis of the
... protection of the secondary hydroxyl group as the benzyl ether and left the primary hydroxyl group, available after oxidation to the aldehyde, for a two-carbon chain extension to an α,βunsaturated ester. This ester in turn was reduced to an allylic alcohol which formed the starting material for a se ...
... protection of the secondary hydroxyl group as the benzyl ether and left the primary hydroxyl group, available after oxidation to the aldehyde, for a two-carbon chain extension to an α,βunsaturated ester. This ester in turn was reduced to an allylic alcohol which formed the starting material for a se ...
000217986-Tajbakhsh_et_al_
... silylethers, a,b-unsaturated carbonyl compounds and esters. The reactions were performed in diethyl ether at room temperature or under reflux, and the yields of the corresponding alcohols were excellent. The selective reduction of aldehydes in the presence of ketones and complete regioselectivity in ...
... silylethers, a,b-unsaturated carbonyl compounds and esters. The reactions were performed in diethyl ether at room temperature or under reflux, and the yields of the corresponding alcohols were excellent. The selective reduction of aldehydes in the presence of ketones and complete regioselectivity in ...
top organomet chem-2006-19-207 pauson
... On the other hand, the intramolecular allenic PKR has allowed the efficient synthesis of seven membered rings. Mukai has synthesized bicyclo[5.3.0]decenones (19) from allenynes 18, using several rhodium catalysts. The process tolerates hydroxy and silyloxy groups and generally reaches good yields (Sc ...
... On the other hand, the intramolecular allenic PKR has allowed the efficient synthesis of seven membered rings. Mukai has synthesized bicyclo[5.3.0]decenones (19) from allenynes 18, using several rhodium catalysts. The process tolerates hydroxy and silyloxy groups and generally reaches good yields (Sc ...
Sol-Gel Science for Ceramic Materials - Sigma
... Through sol-gel processing, homogeneous, high-purity inorganic oxide glasses can be made at ambient temperatures rather than at the very high temperatures required in conventional approaches. Various products, such as molded gels,4,5 spun fibers,6,7 thin films,8-10 molecular cages,11,12 and xerogels ...
... Through sol-gel processing, homogeneous, high-purity inorganic oxide glasses can be made at ambient temperatures rather than at the very high temperatures required in conventional approaches. Various products, such as molded gels,4,5 spun fibers,6,7 thin films,8-10 molecular cages,11,12 and xerogels ...
4. High molar extinction coefficient Ru(II)-mixed
... spectrum of black dye, while enhancing the molar extinction coefficient. But the introduction of these bipyridyl ligands shifted the absorption spectrum towards blue region. To understand the molar extinction coefficient’s augment and the blue-shifted absorption spectrum, timedependent density funct ...
... spectrum of black dye, while enhancing the molar extinction coefficient. But the introduction of these bipyridyl ligands shifted the absorption spectrum towards blue region. To understand the molar extinction coefficient’s augment and the blue-shifted absorption spectrum, timedependent density funct ...
Polymerization of methyl acrylate and as comonomer
... The main goal of this research is to find a single-site catalyst system, which can form copolymers of ethylene and methyl acrylate. Single-site catalysts represent the most recent generation of Ziegler/Natta catalysts, which in contrast to the latter only form one active catalytic species. Copolymer ...
... The main goal of this research is to find a single-site catalyst system, which can form copolymers of ethylene and methyl acrylate. Single-site catalysts represent the most recent generation of Ziegler/Natta catalysts, which in contrast to the latter only form one active catalytic species. Copolymer ...
APPLICATION OF IONIC LIQUIDS IN ORGANIC SYNTHESIS
... that separation of products can be achieved using extraction and/or decantation. It should be noted that the tendency of ionic liquids to suppress conventional solvation phenomena should be dramatically different form those occurred in molecular solvents. So far, several classes of ionic liquids hav ...
... that separation of products can be achieved using extraction and/or decantation. It should be noted that the tendency of ionic liquids to suppress conventional solvation phenomena should be dramatically different form those occurred in molecular solvents. So far, several classes of ionic liquids hav ...
Reductions of Carboxylic Acid Derivatives - IDC
... Catalytic Hydrogenation : As a rule, the carbonyl group does not add hydrogen as readily as do the carbon-carbon double and triple bonds. Thus, it is fairly easy to reduce an alkene or alkyne function without affecting any carbonyl functions in the same molecule. By using a platinum catalyst and inc ...
... Catalytic Hydrogenation : As a rule, the carbonyl group does not add hydrogen as readily as do the carbon-carbon double and triple bonds. Thus, it is fairly easy to reduce an alkene or alkyne function without affecting any carbonyl functions in the same molecule. By using a platinum catalyst and inc ...
Ring-closing metathesis
Ring-closing metathesis, or RCM, is a widely used variation of olefin metathesis in organic chemistry for the synthesis of various unsaturated rings via the intramolecular metathesis of two terminal alkenes, which forms the cycloalkene as the E- or Z- isomers and volatile ethylene.The most commonly synthesized ring sizes are between 5-7 atoms; however, reported syntheses include 45- up to 90- membered macroheterocycles. These reactions are metal-catalyzed and proceed through a metallacyclobutane intermediate. It was first published by Dider Villemin in 1980 describing the synthesis of an Exaltolide precursor, and later become popularized by Robert H. Grubbs and Richard R. Schrock, who shared the Nobel Prize in Chemistry, along with Yves Chauvin, in 2005 for their combined work in olefin metathesis. RCM is a favorite among organic chemists due to its synthetic utility in the formation of rings, which were previously difficult to access efficiently, and broad substrate scope. Since the only major by-product is ethylene, these reactions may also be considered atom economic, an increasingly important concern in the development of green chemistry.There are several reviews published on ring-closing metathesis.