Synthesis and thermal decarbonylation of W(CO)5 complexes
... the residual polymeric matrix. This observation could be useful in designing polymeric complexes in order to control the nature of the metal containing particles resulting in the thermal decomposition. On the other hand, the thermograms also indicated that, in the case of 4, and 6b and, even more co ...
... the residual polymeric matrix. This observation could be useful in designing polymeric complexes in order to control the nature of the metal containing particles resulting in the thermal decomposition. On the other hand, the thermograms also indicated that, in the case of 4, and 6b and, even more co ...
A Straightforward Route to Enantiopure Pyrrolizidines and
... homogeneous catalysts for the production of oxygenates [26-33], including methanol, ethanol, and especially ethylene glycol. The principal shortcoming of all homogeneous CO hydrogenation reactions is their low catalytic activity, which results in the need to use high catalyst loadings and drastic re ...
... homogeneous catalysts for the production of oxygenates [26-33], including methanol, ethanol, and especially ethylene glycol. The principal shortcoming of all homogeneous CO hydrogenation reactions is their low catalytic activity, which results in the need to use high catalyst loadings and drastic re ...
On The catalytic Hydrogenation of Co2 and Carboxylic acid esters
... processes ranging from oil refining and fuel production to fine chemical synthesis of pharmaceuticals. After a century of research and development, hydrogenation catalysts evolved from bulk metal powders and clays into sophisticated, rationally designed multicomponent heterogeneous and homogeneous s ...
... processes ranging from oil refining and fuel production to fine chemical synthesis of pharmaceuticals. After a century of research and development, hydrogenation catalysts evolved from bulk metal powders and clays into sophisticated, rationally designed multicomponent heterogeneous and homogeneous s ...
Novel Synthesis of Schiff bases Bearing Glucosamine Moiety
... with salicylaldehyde have been shown to give stable complexes with transition-metal ions such as Cu (II), Fe (III), and Co (II) and can be applied as asymmetric catalysts14. On the other hand Pérez et al. have reported the first detailed study on the Schiff bases formed by reaction of D-glucosamine ...
... with salicylaldehyde have been shown to give stable complexes with transition-metal ions such as Cu (II), Fe (III), and Co (II) and can be applied as asymmetric catalysts14. On the other hand Pérez et al. have reported the first detailed study on the Schiff bases formed by reaction of D-glucosamine ...
Enantioselective Organocatalytic Aminomethylation of Aldehydes: A
... gave a 72% yield of material with >98% ee. The benzyl groups were removed and replaced by Boc in an efficient one-pot operation. Jones oxidation12 then provided desired β2-amino acid product after simple extraction, with >50% overall yield from A. The route is short, and purifications are simple; th ...
... gave a 72% yield of material with >98% ee. The benzyl groups were removed and replaced by Boc in an efficient one-pot operation. Jones oxidation12 then provided desired β2-amino acid product after simple extraction, with >50% overall yield from A. The route is short, and purifications are simple; th ...
Oxidation Reactions
... This is one of the most important and successful catalytic asymmetric processes developed to date. It is widely used, simple to carry out and is applicable to almost any alkene substrate. It is also relatively predictable in its outcome. The reaction is normally under REAGENT CONTROL i.e. the chiral ...
... This is one of the most important and successful catalytic asymmetric processes developed to date. It is widely used, simple to carry out and is applicable to almost any alkene substrate. It is also relatively predictable in its outcome. The reaction is normally under REAGENT CONTROL i.e. the chiral ...
48 Inorganic Discussion Weekend 48 Rencontres
... Department of Chemistry and Chemical Engineering, Royal Military College of Canada Ken Reimer received his BSc (1969) and MSc (1971) degrees from the University of Calgary; the latter dealing with tungsten and molybdenum complexes and his PhD (1975) from the University of Western Ontario in organome ...
... Department of Chemistry and Chemical Engineering, Royal Military College of Canada Ken Reimer received his BSc (1969) and MSc (1971) degrees from the University of Calgary; the latter dealing with tungsten and molybdenum complexes and his PhD (1975) from the University of Western Ontario in organome ...
1 Introduction
... Nearly a whole kilogram of waste for every kilogram of product! Remember, this is for the ideal case of 100% yield and 100% selectivity. In real life, the E-factor is usually much higher, because product yields are less than 100% and the reagents are often used in excess. Furthermore, in many cases ...
... Nearly a whole kilogram of waste for every kilogram of product! Remember, this is for the ideal case of 100% yield and 100% selectivity. In real life, the E-factor is usually much higher, because product yields are less than 100% and the reagents are often used in excess. Furthermore, in many cases ...
W19 Aldehydes ketones I
... physical properties of aldehydes and ketones reaction scheme of aldehydes and ketones nucleophilic addition AN to C=O group: cyanohydrins, hemiacetals, acetals, thioacetals nucleophilic addition-elimination AN(E) to C=O group: imines, oximes, hydrazones, enamines nucleophilic addition of phosphorus ...
... physical properties of aldehydes and ketones reaction scheme of aldehydes and ketones nucleophilic addition AN to C=O group: cyanohydrins, hemiacetals, acetals, thioacetals nucleophilic addition-elimination AN(E) to C=O group: imines, oximes, hydrazones, enamines nucleophilic addition of phosphorus ...
friedel-craft reaction: a review - Advance Institute of Biotech
... amino acids are well known.However much attention has been focused on L-proline, an inexpensive, and efficient catalyst. L-Proline has been found to be very effective in enamine-based direct catalytic asymmetricaldol, Mannich, Diels–Alder, and Knoevenagel type of reactions.14 Methylenecyclopropanes ...
... amino acids are well known.However much attention has been focused on L-proline, an inexpensive, and efficient catalyst. L-Proline has been found to be very effective in enamine-based direct catalytic asymmetricaldol, Mannich, Diels–Alder, and Knoevenagel type of reactions.14 Methylenecyclopropanes ...
Oxo-molybdenum(VI) - Repositório da Universidade Nova de Lisboa
... triggers its capability to catalyze different kind of processes such as carbon-carbon bond formation, olefin metathesis or alkene epoxidation among the most relevant transformations. ...
... triggers its capability to catalyze different kind of processes such as carbon-carbon bond formation, olefin metathesis or alkene epoxidation among the most relevant transformations. ...
Resolution of Diols via Catalytic Asymmetric Acetalization
... although a higher catalyst loading was required (entry 4). When even more sterically demanding pivalaldehyde was used, the reaction did not proceed at all (entry 5). Considering that the use of isovaleraldehyde, which is bulkier than linear aldehydes and at the same time less bulky than α-trisubstit ...
... although a higher catalyst loading was required (entry 4). When even more sterically demanding pivalaldehyde was used, the reaction did not proceed at all (entry 5). Considering that the use of isovaleraldehyde, which is bulkier than linear aldehydes and at the same time less bulky than α-trisubstit ...
Synthesis of a TREN in Which the Aryl Substituents are... Atom Macrocycle ̈ller *
... reduced. Eight of the proposed catalytic intermediates in the Mocatalyzed TREN-based system were characterized by X-ray crystallography. The proposed reaction mechanism also has been scrutinized through extensive calculations.2 All steric and electronic modifications of the successful “HIPT catalysts ...
... reduced. Eight of the proposed catalytic intermediates in the Mocatalyzed TREN-based system were characterized by X-ray crystallography. The proposed reaction mechanism also has been scrutinized through extensive calculations.2 All steric and electronic modifications of the successful “HIPT catalysts ...
Week 1 - School of Chemical Sciences
... W. Knowles: Replacement of achiral PPh3 ligands with non-racemic phosphines ((-)-methylpropylphenylphosphine, 69%ee) demonstrated that a chiral transition metal complex could transfer chirality to a non-chiral substrate during hydrogenation. ...
... W. Knowles: Replacement of achiral PPh3 ligands with non-racemic phosphines ((-)-methylpropylphenylphosphine, 69%ee) demonstrated that a chiral transition metal complex could transfer chirality to a non-chiral substrate during hydrogenation. ...
Direct conversion of cellulose into sorbitol using dual
... respectively. Liquid-phase mineral acids or heteropolyacids have been used together with metal catalysts containing Pt or Ru [8,9]. These acids, however, are difficult to recover and can cause corrosion of the reactor. In addition, a large amount of waste sludge is formed in the acid neutralization p ...
... respectively. Liquid-phase mineral acids or heteropolyacids have been used together with metal catalysts containing Pt or Ru [8,9]. These acids, however, are difficult to recover and can cause corrosion of the reactor. In addition, a large amount of waste sludge is formed in the acid neutralization p ...
CHAPTER 13 Approaches to the Asymmetric Synthesis of Unusual
... 3. Dlastereoselectlve Strecker and Ugl reactions with optically active ammes; and 4. Diastereoselective hydrogenation of a, P-dehydroammo acid derivatives. ...
... 3. Dlastereoselectlve Strecker and Ugl reactions with optically active ammes; and 4. Diastereoselective hydrogenation of a, P-dehydroammo acid derivatives. ...
15_01_05.html
... principal use: preparation of formaldehyde prepared by hydrogenation of carbon monoxide CO + 2H2 CH3OH ...
... principal use: preparation of formaldehyde prepared by hydrogenation of carbon monoxide CO + 2H2 CH3OH ...
Chapter 1 Chirality in clinical analysis 1.1. Introduction
... The term “Chirality” (from the Greek kheir for hand), means handedness, which is the existence of left/right opposites. The concept of “Chirality” has been known in chemistry since the 1870’s although a hundred years passed before chemists began using this term. In 1962, the first edition of Eliel’s ...
... The term “Chirality” (from the Greek kheir for hand), means handedness, which is the existence of left/right opposites. The concept of “Chirality” has been known in chemistry since the 1870’s although a hundred years passed before chemists began using this term. In 1962, the first edition of Eliel’s ...
1 Bite Angle Effects of Diphosphines in Carbonylation Reactions
... The hydroformylation of alkenes is one of the most extensively applied homogeneous catalytic processes in industry. More than 9 million tons of aldehydes and alcohols are produced annually [13]. Many efforts have been devoted in the last few years to the development of systems with improved regiosel ...
... The hydroformylation of alkenes is one of the most extensively applied homogeneous catalytic processes in industry. More than 9 million tons of aldehydes and alcohols are produced annually [13]. Many efforts have been devoted in the last few years to the development of systems with improved regiosel ...
Chapter 4 Stereochemistry and Chirality Flow chart for determining
... Enantiotopic: If you have a methylene group of the form X- CH2 -Z, and you replace one of the hydrogens of the CH2 with a dummy atom and then you independently replace the other hydrogen of the CH 2 group with a dummy atom (Y), the two molecules thus created will be enantiomers of each other. The pr ...
... Enantiotopic: If you have a methylene group of the form X- CH2 -Z, and you replace one of the hydrogens of the CH2 with a dummy atom and then you independently replace the other hydrogen of the CH 2 group with a dummy atom (Y), the two molecules thus created will be enantiomers of each other. The pr ...
C 1 hapter
... (3) alkylboronate ester products (Table 1) depends on the catalytic system, the ligand and the borane reagent. Unfortunately, however, until now this has not been well understood. Hayashi et al. suggested that the high internal selectivity of the catalytic hydroboration of vinylarenes on the branche ...
... (3) alkylboronate ester products (Table 1) depends on the catalytic system, the ligand and the borane reagent. Unfortunately, however, until now this has not been well understood. Hayashi et al. suggested that the high internal selectivity of the catalytic hydroboration of vinylarenes on the branche ...
Liquid-gas phase-boundary catalytic system
... simulation theory. The use of TiO2 as inorganic precursor and organic surfactant, however, has not been reported. In our recent report [5 ], well-aligned titanium dioxide was successfully synthesized by sol-gel method by using tetra-n-butyl orthotitanate (TBOT) as titanium dioxide precursor. Wellali ...
... simulation theory. The use of TiO2 as inorganic precursor and organic surfactant, however, has not been reported. In our recent report [5 ], well-aligned titanium dioxide was successfully synthesized by sol-gel method by using tetra-n-butyl orthotitanate (TBOT) as titanium dioxide precursor. Wellali ...
as a PDF
... demand growth for basic oleochemicals: fatty acids and fatty alcohols. Oleochemicals are starting to replace crude oil derived products in various applications. As widely practiced in petrochemical industry, catalyst plays a very important role in the production of basic oleochemicals. Catalytic rea ...
... demand growth for basic oleochemicals: fatty acids and fatty alcohols. Oleochemicals are starting to replace crude oil derived products in various applications. As widely practiced in petrochemical industry, catalyst plays a very important role in the production of basic oleochemicals. Catalytic rea ...
Ion Exchange Resins: Catalyst Recovery and Recycle
... fits most “principles of green chemistry”1-4 and was included as a priority in several strategic research agendas both in the United States and in Europe.5,6 To date, catalytic technologies leading to fine-chemicals production, and particularly in selective, large-scale processes, are still largely ...
... fits most “principles of green chemistry”1-4 and was included as a priority in several strategic research agendas both in the United States and in Europe.5,6 To date, catalytic technologies leading to fine-chemicals production, and particularly in selective, large-scale processes, are still largely ...
Synthesis of Four Diastereomeric 3,5-Dialkoxy-2,4
... to 9 and 11, derived from the epoxy alcohols having the opposite stereochemistry about the epoxide (5 and 6), did not react under these conditions, giving back mostly starting materials. However, treatment of the mesylate alcohol 13 (prepared from 5 in four steps and 61% overall yield) with TESCl fo ...
... to 9 and 11, derived from the epoxy alcohols having the opposite stereochemistry about the epoxide (5 and 6), did not react under these conditions, giving back mostly starting materials. However, treatment of the mesylate alcohol 13 (prepared from 5 in four steps and 61% overall yield) with TESCl fo ...
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.