Palladium and Ruthenium Catalyzed Reactions By Bryan Jaksic
... certain instances. The rate and quantity of active species generated is not known for the commonly used precatalysts and is a potential reason for decreased rates and yields. Norton et al. have recently demonstrated that the newly synthesized, easily handled compound Pd(η5-C5H5)(η31-Ph-C3H4) is a su ...
... certain instances. The rate and quantity of active species generated is not known for the commonly used precatalysts and is a potential reason for decreased rates and yields. Norton et al. have recently demonstrated that the newly synthesized, easily handled compound Pd(η5-C5H5)(η31-Ph-C3H4) is a su ...
... complexes that have had such a dramatic influence on modern organic synthesis. Schrock`s creation of the first well-defined useful catalysts Many researchers foresaw the great synthetic potential of metathesis. But applications to organic chemistry were generally complicated by the sensitivity of th ...
Reductive Deoxygenation of Ketones and Secondary Alcohols by
... has been achieved in good to excellent yield by the combined action of an aluminum hydride source and a strongly Lewis-acidic aluminum reagent. Such reductions were successful with diaryl ketones, alkyl aryl ketones, and dialkyl ketones, as exemplified by the reduction of benzophenone, acetophenone ...
... has been achieved in good to excellent yield by the combined action of an aluminum hydride source and a strongly Lewis-acidic aluminum reagent. Such reductions were successful with diaryl ketones, alkyl aryl ketones, and dialkyl ketones, as exemplified by the reduction of benzophenone, acetophenone ...
Dehydration of n-propanol and methanol to produce
... and pressure, around 350 °C and 180 bar respectively [13]. However, MPE comprised of only 2.5% of the bio-crude produced. Other work done on methanol-isobutanol, ethanol-isobutanol and, ethanol etherification [11] also followed dehydration principle [14]. Above examples show that dehydration is a fe ...
... and pressure, around 350 °C and 180 bar respectively [13]. However, MPE comprised of only 2.5% of the bio-crude produced. Other work done on methanol-isobutanol, ethanol-isobutanol and, ethanol etherification [11] also followed dehydration principle [14]. Above examples show that dehydration is a fe ...
Richard R. Schrock - Nobel Lecture
... known. When I went to the Central Research Department of E. I. DuPont de Nemours and Company in 1972, transition metal organometallic chemistry and homogeneous catalysis were of great interest as a consequence of their huge potential in organic chemistry and therefore in industry. In the early 1970’ ...
... known. When I went to the Central Research Department of E. I. DuPont de Nemours and Company in 1972, transition metal organometallic chemistry and homogeneous catalysis were of great interest as a consequence of their huge potential in organic chemistry and therefore in industry. In the early 1970’ ...
asian journal of chemistry asian journal of chemistry
... of low heat transfer and easy automation and incident power ...
... of low heat transfer and easy automation and incident power ...
Chapter 19. Aldehydes and Ketones: Nucleophilic Addition
... • Can be used for monosubstituted, disubstituted, and trisubstituted alkenes but not tetrasubstituted alkenes The reaction yields a pure alkene of known structure • For comparison, addition of CH3MgBr to cyclohexanone and dehydration with, yields a mixture of two alkenes ...
... • Can be used for monosubstituted, disubstituted, and trisubstituted alkenes but not tetrasubstituted alkenes The reaction yields a pure alkene of known structure • For comparison, addition of CH3MgBr to cyclohexanone and dehydration with, yields a mixture of two alkenes ...
CHAPTER V Fischer-Tropsch Syncrude
... why refining of syncrude should be approached differently to crude oil refining. Emphasis is placed on olefins and oxygenates, because it is these compound classes that differentiate syncrude from crude oil. Although Fischer-Tropsch plants are often classified in terms of feed material as coalto-liq ...
... why refining of syncrude should be approached differently to crude oil refining. Emphasis is placed on olefins and oxygenates, because it is these compound classes that differentiate syncrude from crude oil. Although Fischer-Tropsch plants are often classified in terms of feed material as coalto-liq ...
Oxidation of benzoin with anchored vanadyl and
... the products analysed by HPLC. The metal-ion content of the supported catalysts and the yields of the product benzil obtained are given in Table 2. It was observed that with some of the catalysts, methyl benzoate and benzoic acid were also obtained along with benzil. As three different products were ...
... the products analysed by HPLC. The metal-ion content of the supported catalysts and the yields of the product benzil obtained are given in Table 2. It was observed that with some of the catalysts, methyl benzoate and benzoic acid were also obtained along with benzil. As three different products were ...
Chapter 1 - University of Amsterdam
... states become quite misleading, and no longer represent the true ‘d-electron’ configurations as the bonding and anti-bonding combinations can no longer be assigned being either of mainly ligand or mainly metal character (Figure 4, middle). The ‘real’ or spectroscopic oxidation state of such complexe ...
... states become quite misleading, and no longer represent the true ‘d-electron’ configurations as the bonding and anti-bonding combinations can no longer be assigned being either of mainly ligand or mainly metal character (Figure 4, middle). The ‘real’ or spectroscopic oxidation state of such complexe ...
kinetic characterisation of catalysts for methanol synthesis
... Nowadays Cu/ZnO/Al2O3 catalyst is commonly used in chemical industry to produce methanol. The catalyst is produced in the shape of Raschig rings or tablets. The company Johnson Matthey produces a catalyst called KATALCO which is the standard of Cu/ZnO/Al2O3. A new generation of catalysts also based ...
... Nowadays Cu/ZnO/Al2O3 catalyst is commonly used in chemical industry to produce methanol. The catalyst is produced in the shape of Raschig rings or tablets. The company Johnson Matthey produces a catalyst called KATALCO which is the standard of Cu/ZnO/Al2O3. A new generation of catalysts also based ...
Isomers and Isomerism Isomers
... They have the same numbers of same kinds of atoms, but the differ in the way that those atoms are attached to one another, or how they are oriented in space,(Greek: isos= equal; meros=part) Isomerism The presence of two or more compounds which has the same molecular formula is known as Isomerism 1. ...
... They have the same numbers of same kinds of atoms, but the differ in the way that those atoms are attached to one another, or how they are oriented in space,(Greek: isos= equal; meros=part) Isomerism The presence of two or more compounds which has the same molecular formula is known as Isomerism 1. ...
Direct organocatalytic enantioselective a-aminomethylation
... Trost and co-workers12 developed di-nuclear zinc organometallic complexes as catalyst for the direct catalytic enantioselective Mannich-type reactions between hydroxyarylketones and preformed imines. In addition, Jørgensen and co-workers have developed elegant direct asymmetric Mannich reactions inv ...
... Trost and co-workers12 developed di-nuclear zinc organometallic complexes as catalyst for the direct catalytic enantioselective Mannich-type reactions between hydroxyarylketones and preformed imines. In addition, Jørgensen and co-workers have developed elegant direct asymmetric Mannich reactions inv ...
Synthesis of the hexoses
... nl., the regioselectivities are generally high with “oxygenated (at C-4)” substrateslsb and undesired regioisomers are easily separated by chromatography. This route also provides easy access to the aldehyde ti oxidation ...
... nl., the regioselectivities are generally high with “oxygenated (at C-4)” substrateslsb and undesired regioisomers are easily separated by chromatography. This route also provides easy access to the aldehyde ti oxidation ...
Zinc Alkyls in Organic Synthesis
... Dimethylzinc (DMZ) has been used in similar ways as DEZ in organic reactions. Because DMZ is highly volatile (bp 44°C), accurate addition of the reagent into the reaction mixture can be difficult. When the reaction mixture is not cooled to a low temperature, a portion of the DMZ added will vaporize ...
... Dimethylzinc (DMZ) has been used in similar ways as DEZ in organic reactions. Because DMZ is highly volatile (bp 44°C), accurate addition of the reagent into the reaction mixture can be difficult. When the reaction mixture is not cooled to a low temperature, a portion of the DMZ added will vaporize ...
Carbohydrates
... Chirality: handedness in molecules • “Handedness” is a feature that an object possesses by virtue of its symmetry. When an object has a handedness (e.g. right- or left-), its mirror image cannot be superimposed upon it (the mirror image and object are non-superimposable) • Non-superimposable means ...
... Chirality: handedness in molecules • “Handedness” is a feature that an object possesses by virtue of its symmetry. When an object has a handedness (e.g. right- or left-), its mirror image cannot be superimposed upon it (the mirror image and object are non-superimposable) • Non-superimposable means ...
Triruthenium and triosmium carbonyl clusters containing chiral
... nitrogen, using Schlenk-vacuum line techniques, and were routinely monitored by solution IR spectroscopy (carbonyl stretching region) and spot TLC. Levamisole,2 methyl levamisolium triflate,2 [Os3 (CO)10 (MeCN)2 ],22 [NH4 ][Ru3 (l-H)(CO)11 ],23 and [PPN][Os3 (l-H)(CO)11 ]24 were prepared following pu ...
... nitrogen, using Schlenk-vacuum line techniques, and were routinely monitored by solution IR spectroscopy (carbonyl stretching region) and spot TLC. Levamisole,2 methyl levamisolium triflate,2 [Os3 (CO)10 (MeCN)2 ],22 [NH4 ][Ru3 (l-H)(CO)11 ],23 and [PPN][Os3 (l-H)(CO)11 ]24 were prepared following pu ...
REDUCTIONS AND REDUCING AGENTS
... Lithium aluminiumhydride reacts the same way as lithium borohydride. It is however a much more reactive reducing agent than lithium borohydride. It is the strongest of the hydride reducing agents. Note that the Al-H bond is more polarized than B-H bond. Consequently the hydride in Al-H has greater h ...
... Lithium aluminiumhydride reacts the same way as lithium borohydride. It is however a much more reactive reducing agent than lithium borohydride. It is the strongest of the hydride reducing agents. Note that the Al-H bond is more polarized than B-H bond. Consequently the hydride in Al-H has greater h ...
Copper perchlorate: Efficient acetylation catalyst
... at 85 ◦ C drives the reaction faster but requires about 2 h for heteroatoms [2d]. For benzaldehyde refluxing is not very effective in the absence of catalyst even after a period of 24 h. To check the catalyst efficiency in general (conditions: at room temperature in the presence of catalyst), after ...
... at 85 ◦ C drives the reaction faster but requires about 2 h for heteroatoms [2d]. For benzaldehyde refluxing is not very effective in the absence of catalyst even after a period of 24 h. To check the catalyst efficiency in general (conditions: at room temperature in the presence of catalyst), after ...
Changing counterion can switch the preference for selective 1,2
... Regioisomer: The positional isomers formed from different locations of bond formation/cleavage. Note: The term “regiospecific” to refer to a reaction that is 100% regioselective is discouraged, and has no correlation to the difference between “stereoselective” and “stereospecific” ...
... Regioisomer: The positional isomers formed from different locations of bond formation/cleavage. Note: The term “regiospecific” to refer to a reaction that is 100% regioselective is discouraged, and has no correlation to the difference between “stereoselective” and “stereospecific” ...
TOPIC 7. ELIMINATION REACTIONS (chapter 7 and parts of
... SYNTHETIC STRATEGIES: TWO (OR MORE) STEP SYNTHESES ...
... SYNTHETIC STRATEGIES: TWO (OR MORE) STEP SYNTHESES ...
Week of Sept. 20
... 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. ...
Acylation of aromatic alcohols and phenols over InCl3
... from 7 to 96% on increasing the InCl3 loading from zero to 20%. The results clearly show that InCl3 (20%)/Mont. K-10 is a much superior catalyst than the Mont. K-10 without InCl3. It may be noted that use of InCl3 as a catalyst has also been reported earlier in a number of other other organic reacti ...
... from 7 to 96% on increasing the InCl3 loading from zero to 20%. The results clearly show that InCl3 (20%)/Mont. K-10 is a much superior catalyst than the Mont. K-10 without InCl3. It may be noted that use of InCl3 as a catalyst has also been reported earlier in a number of other other organic reacti ...
Amine-functionalized boehmite nanoparticle-supported
... The Mo(CO)6 and VOSO4·H2O complexes were used to sup‐ port on BNPs or AFBNPs (Scheme 1). For this purpose, Mo(CO)6 (0.276 g, 1.05 mmol) was activated under ultraviolet light in tetrahydrofuran (THF, 20.0 mL) for 30 min. This acti‐ vated molybdenum complex was then added to ...
... The Mo(CO)6 and VOSO4·H2O complexes were used to sup‐ port on BNPs or AFBNPs (Scheme 1). For this purpose, Mo(CO)6 (0.276 g, 1.05 mmol) was activated under ultraviolet light in tetrahydrofuran (THF, 20.0 mL) for 30 min. This acti‐ vated molybdenum complex was then added to ...
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.