Catalytic polymeric membranes: Preparation and application
... polymeric membranes are pushing the envelope for their application. A number of studies as a result have also appeared discussing the use of such membranes on high temperatures catalytic membrane reactor application [8]. Dense polymeric membranes for the separation of gases, vapours or liquids from ...
... polymeric membranes are pushing the envelope for their application. A number of studies as a result have also appeared discussing the use of such membranes on high temperatures catalytic membrane reactor application [8]. Dense polymeric membranes for the separation of gases, vapours or liquids from ...
Curriculum Vitae
... Total Award Amount: $1,196,000 (total); $200,000 direct/yr PUBLICATIONS (*indicates corresponding author, §undergraduate coworker): 130. Weldy, N. M.; Schafer, A. G.; Owens, C. P.; Herting, C. J.; Varela-Alvarez, A.; Chen, S.; Niemeyer, Z. L.; Musaev, D. G.*; Sigman, M. S.*; Davies, H. M. L.*; Blake ...
... Total Award Amount: $1,196,000 (total); $200,000 direct/yr PUBLICATIONS (*indicates corresponding author, §undergraduate coworker): 130. Weldy, N. M.; Schafer, A. G.; Owens, C. P.; Herting, C. J.; Varela-Alvarez, A.; Chen, S.; Niemeyer, Z. L.; Musaev, D. G.*; Sigman, M. S.*; Davies, H. M. L.*; Blake ...
Chiral Enolate Equivalents
... confines the range of usable electrophiles to aldehydes, some primary or activated alkyl halides, unsaturated carbonyls, electrophilic halogens, oxaziridines, aza compounds, and a handful of other reactive electrophiles.3 Intramolecular reactions may tolerate slightly less reactive electrophiles. Wi ...
... confines the range of usable electrophiles to aldehydes, some primary or activated alkyl halides, unsaturated carbonyls, electrophilic halogens, oxaziridines, aza compounds, and a handful of other reactive electrophiles.3 Intramolecular reactions may tolerate slightly less reactive electrophiles. Wi ...
1H-Imidazol-4(5H)-ones and thiazol-4(5H)
... enolate or equivalent is fixed due to their cyclic nature, thus facilitating the control of the stereoselectivity; iii) they are substituted at the α-position of the carbonyl and therefore, after reaction with an electrophile, a tetrasubstituted stereocenter is created and, iv) the resulting adducts ...
... enolate or equivalent is fixed due to their cyclic nature, thus facilitating the control of the stereoselectivity; iii) they are substituted at the α-position of the carbonyl and therefore, after reaction with an electrophile, a tetrasubstituted stereocenter is created and, iv) the resulting adducts ...
Catalytic Asymmetric Induction. Highly Enantioselective Addition of
... took place smoothly, as under the above described catalytic conditions, leading to the desired alcohol in 98% ee and in 88% (benza1dehyde:diethyIzinc:DAIB = 1:2:1, 12 h) or 49% (1:1:0.5 ratio, 12 h) yield. These results indicate that two zinc species per aldehyde are responsible for the alkylation r ...
... took place smoothly, as under the above described catalytic conditions, leading to the desired alcohol in 98% ee and in 88% (benza1dehyde:diethyIzinc:DAIB = 1:2:1, 12 h) or 49% (1:1:0.5 ratio, 12 h) yield. These results indicate that two zinc species per aldehyde are responsible for the alkylation r ...
Mannich Reaction - SUST Repository
... The mechanism of the Mannich reaction has been well investigated, the condensation reaction occurs in two steps: first, the amine reacts with formaldehyde to give condensation product (5 ), (6), ( 7) (step I) which then attacks the substrate R-H (step II) .The reaction does not normally follow the o ...
... The mechanism of the Mannich reaction has been well investigated, the condensation reaction occurs in two steps: first, the amine reacts with formaldehyde to give condensation product (5 ), (6), ( 7) (step I) which then attacks the substrate R-H (step II) .The reaction does not normally follow the o ...
The catalytic function of a silica gel-immobilized Mn(II)
... range of alkenes [6]. Manganese porphyrin complexes have been extensively investigated as models for enzymes and used in catalysis with various single oxygen atom donors including H2 O2 [7]. Alkene epoxidation reactions catalyzed by manganese complexes in homogeneous and heterogeneous media and the ...
... range of alkenes [6]. Manganese porphyrin complexes have been extensively investigated as models for enzymes and used in catalysis with various single oxygen atom donors including H2 O2 [7]. Alkene epoxidation reactions catalyzed by manganese complexes in homogeneous and heterogeneous media and the ...
Rhenium Nanochemistry for Catalyst Preparation
... matrix it has been proven possible to transform tertiary amides into their corresponding amines using high pressure hydrogen atmosphere [13]. Rhenium-nickel oxide has been reported as an efficient catalyst for the water gas shift reaction [14]. Re-containing catalysts showed high performance for sel ...
... matrix it has been proven possible to transform tertiary amides into their corresponding amines using high pressure hydrogen atmosphere [13]. Rhenium-nickel oxide has been reported as an efficient catalyst for the water gas shift reaction [14]. Re-containing catalysts showed high performance for sel ...
Copper-catalysed selective hydroamination reactions of alkynes Please share
... vinylcopper species 11. In the absence of a proton source (alcohol), direct interception by electrophilic amine 2 (likely via oxidative addition/reductive elimination) would produce the (E)-enamine product 4 and copper benzoate complex 13 that, upon transmetalation with hydrosilane, would regenerate ...
... vinylcopper species 11. In the absence of a proton source (alcohol), direct interception by electrophilic amine 2 (likely via oxidative addition/reductive elimination) would produce the (E)-enamine product 4 and copper benzoate complex 13 that, upon transmetalation with hydrosilane, would regenerate ...
MS PowerPoint - Catalysis Eprints database
... Idemitsu, Conaco, Shell (SHOP), SABIC ( -SABLIN) Basis for the production of wide range of useful olefins & monomers ...
... Idemitsu, Conaco, Shell (SHOP), SABIC ( -SABLIN) Basis for the production of wide range of useful olefins & monomers ...
EFFECT OF LEWIS ACID IN TiCl4/MgCl2/THF/AlCl3 CATALYST
... The Ziegler-Natta (ZN) catalyst system for ethylene polymerization by combinations of transition metal and organometallic compound has been discovered since 1950s. In general, heterogeneous ZN catalyst is based on titanium chloride supported on magnesium dichloride (TiCl4/MgCl2). MgCl2 is suitable s ...
... The Ziegler-Natta (ZN) catalyst system for ethylene polymerization by combinations of transition metal and organometallic compound has been discovered since 1950s. In general, heterogeneous ZN catalyst is based on titanium chloride supported on magnesium dichloride (TiCl4/MgCl2). MgCl2 is suitable s ...
Synthetic applications of ortho esters
... In contrast to acetal derivatives of carbonyl compounds, ortho esters have found surprisingly limited use in organic synthesis [1]. Since ortho esters are among the few carboxylic acid protective groups that demonstrate a high level of stability toward strong nucleophiles and bases, most current app ...
... In contrast to acetal derivatives of carbonyl compounds, ortho esters have found surprisingly limited use in organic synthesis [1]. Since ortho esters are among the few carboxylic acid protective groups that demonstrate a high level of stability toward strong nucleophiles and bases, most current app ...
Lecture8
... Ligands bound to metal centers often have quite different reactivity from the free compound. Many bound ligands can be modified or removed from the metal center by nucleophilic or electrophilic reactions. Often these reactions involve direct attack on the bound ligand. Nucleophilic attack: Favored f ...
... Ligands bound to metal centers often have quite different reactivity from the free compound. Many bound ligands can be modified or removed from the metal center by nucleophilic or electrophilic reactions. Often these reactions involve direct attack on the bound ligand. Nucleophilic attack: Favored f ...
Factors influencing ring closure through olefin metathesis – A
... way of obtaining rings. Commonly employed cyclization methods involve reactions of cationic, anionic or radical species. Common rings such as 5–7 membered ones are easily available by these methods. However, formation of medium or large rings by these methods either proceeds with low yields or does ...
... way of obtaining rings. Commonly employed cyclization methods involve reactions of cationic, anionic or radical species. Common rings such as 5–7 membered ones are easily available by these methods. However, formation of medium or large rings by these methods either proceeds with low yields or does ...
Effect of Potassium on Sol-Gel Cerium and Lanthanum Oxide
... Therefore, the catalysts used in the catalytic combustion of soot must be capable of presenting catalyst activity at low temperatures [10]. An important number of catalytic formulations have been developed in this field, including oxides [11]-[14], perovskites [9] [15]-[17], spinels [18] and metals ...
... Therefore, the catalysts used in the catalytic combustion of soot must be capable of presenting catalyst activity at low temperatures [10]. An important number of catalytic formulations have been developed in this field, including oxides [11]-[14], perovskites [9] [15]-[17], spinels [18] and metals ...
Catalytic, Enantioselective Alkylations of N,O- and
... Mechanism. To our surprise, the use of one equiv enol silane 4a with N,O-acetal l a did not lead to product 5a with 5 mol% 2; however, when two equiv were used, product 5a was formed in good yield. Although silyl ketene acetals can be quenched through silyl transfer reactions with alcohols, enol sil ...
... Mechanism. To our surprise, the use of one equiv enol silane 4a with N,O-acetal l a did not lead to product 5a with 5 mol% 2; however, when two equiv were used, product 5a was formed in good yield. Although silyl ketene acetals can be quenched through silyl transfer reactions with alcohols, enol sil ...
New insights into the mechanism of sorbitol transformation
... and hemicellulose, polymers of hexoses and pentoses, and lignin, a macromolecule containing phenolic groups [2]. Cellulose and hemicellulose can be hydrolyzed into the corresponding sugar monomers [3]. However, the resilient nature of crystalline cellulose requires harsh hydrolysis conditions which ...
... and hemicellulose, polymers of hexoses and pentoses, and lignin, a macromolecule containing phenolic groups [2]. Cellulose and hemicellulose can be hydrolyzed into the corresponding sugar monomers [3]. However, the resilient nature of crystalline cellulose requires harsh hydrolysis conditions which ...
First palladium- and nickel-catalyzed oxidative
... which can be converted to the free pyrrolidine-2-methylamines by LAH reduction. Alternatively, directly removal of both protection groups is feasible [14,15]. Recent efforts dealt with the development of related diamination reactions for the construction of cyclic guanidines from 1,2-diamination (Sc ...
... which can be converted to the free pyrrolidine-2-methylamines by LAH reduction. Alternatively, directly removal of both protection groups is feasible [14,15]. Recent efforts dealt with the development of related diamination reactions for the construction of cyclic guanidines from 1,2-diamination (Sc ...
proline catalyzed direct asymmetric aldol and mannich reactions
... acceptors were reported (Table 1, 15, 16). 11 List reported that cross-aldol reaction with linear aldehydes as acceptors was dependent on solvent. Use of either 20% v/v acetone in chloroform or pure acetone as solvent suppressed aldehyde self-aldolization under the long reaction times of 3 to 7 days ...
... acceptors were reported (Table 1, 15, 16). 11 List reported that cross-aldol reaction with linear aldehydes as acceptors was dependent on solvent. Use of either 20% v/v acetone in chloroform or pure acetone as solvent suppressed aldehyde self-aldolization under the long reaction times of 3 to 7 days ...
A manganese catalyst for highly reactive yet chemoselective
... readily oxidizable π functionality1–6. Intramolecular metallonitrene-based C(sp 3)–H amination of sulfamate esters, which installs medicinally important amino alcohol motifs, showcases the inverse correlation between reactivity and chemoselectivity for such catalysis7–10. Noble metal rhodium catalys ...
... readily oxidizable π functionality1–6. Intramolecular metallonitrene-based C(sp 3)–H amination of sulfamate esters, which installs medicinally important amino alcohol motifs, showcases the inverse correlation between reactivity and chemoselectivity for such catalysis7–10. Noble metal rhodium catalys ...
homogeneous catalysis
... and industrial research laboratories the growth in research activity in this area in the past decade or so has been phenomenal. Written mainly from a pedagogical point of view, this book is not comprehensive but selective. The material presented was selected on the basis of two criteria. We have tri ...
... and industrial research laboratories the growth in research activity in this area in the past decade or so has been phenomenal. Written mainly from a pedagogical point of view, this book is not comprehensive but selective. The material presented was selected on the basis of two criteria. We have tri ...
Chapter One Hemilabile Ligands in Transition
... metal centre. These ligands were first described in a kinetic context as “hemilabile ligands” in 1979 by Jeffrey and Rauchfuss.8 ...
... metal centre. These ligands were first described in a kinetic context as “hemilabile ligands” in 1979 by Jeffrey and Rauchfuss.8 ...
Enol esters: Versatile substrates in synthesis of fine and specialty
... acidic conditions with mostly retention of configuration. Both α-acyloxy ketones and their αhydroxy ketone derivatives, are essential in synthesis of alkaloids, sugars, antibiotics, terpenes and pheromones, for they function as stereodirective groups or chiral synthons. Zhu et al. practised the rear ...
... acidic conditions with mostly retention of configuration. Both α-acyloxy ketones and their αhydroxy ketone derivatives, are essential in synthesis of alkaloids, sugars, antibiotics, terpenes and pheromones, for they function as stereodirective groups or chiral synthons. Zhu et al. practised the rear ...
Asymmetric hydrogenation
Asymmetric hydrogenation is a chemical reaction that adds two atoms of hydrogen preferentially to one of two faces of an unsaturated substrate molecule, such as an alkene or ketone. The selectivity derives from the manner that the substrate binds to the chiral catalysts. In jargon, this binding transmits spatial information (what chemists refer to as chirality) from the catalyst to the target, favoring the product as a single enantiomer. This enzyme-like selectivity is particularly applied to bioactive products such as pharmaceutical agents and agrochemicals.