top-curr-chem-1990-155-1
... Eq. (5). Reagents prepared either from a zinc/copper couple [13--15] or a zinc/ silver couple [12] have been successfully used for the cyclopropanation of enol silyl ethers from ketones (Table 1). Regioselectivity is noted with polyolefinic substrates, the electron-rich enol silyl ether moiety being ...
... Eq. (5). Reagents prepared either from a zinc/copper couple [13--15] or a zinc/ silver couple [12] have been successfully used for the cyclopropanation of enol silyl ethers from ketones (Table 1). Regioselectivity is noted with polyolefinic substrates, the electron-rich enol silyl ether moiety being ...
Phosphine-Catalyzed Additions of Nucleophiles and Electrophiles to
... stoichiometrically consumed and converted into a phosphine oxide. Phosphines are also commonly used as ligands for transition metal-catalyzed reactions, to modulate reactivity and stereocontrol.4 On the other hand, the use of phosphines as nucleophilic catalysts for organic reactions has only gained ...
... stoichiometrically consumed and converted into a phosphine oxide. Phosphines are also commonly used as ligands for transition metal-catalyzed reactions, to modulate reactivity and stereocontrol.4 On the other hand, the use of phosphines as nucleophilic catalysts for organic reactions has only gained ...
Micellar Catalytic Effect of Cetyltrimethylammonium Bromide
... prepared by ether Williamson reaction or O-allylation via direct allylation by the use of allyl bromide in acetone in the presence of potassium carbonate. However, problems arise when the O-allylation reaction with eugenol. This reaction is ether compounds formation which requires heat conditions bu ...
... prepared by ether Williamson reaction or O-allylation via direct allylation by the use of allyl bromide in acetone in the presence of potassium carbonate. However, problems arise when the O-allylation reaction with eugenol. This reaction is ether compounds formation which requires heat conditions bu ...
1 Chemistry 3720 Exam 2 Spring 2001 This exam is worth 100
... 5. (10 pts) Design an efficient synthesis of the following product using 1-butanol as the only source of carbon. You may use any of the reactions and reagents used so far in 3719 or 3720. Show a complete retrosynthetic analysis of the problem, then the synthetic steps required to produce the compou ...
... 5. (10 pts) Design an efficient synthesis of the following product using 1-butanol as the only source of carbon. You may use any of the reactions and reagents used so far in 3719 or 3720. Show a complete retrosynthetic analysis of the problem, then the synthetic steps required to produce the compou ...
chemical equilibrium in a liquid phase
... Calculations.-Since the weights of sulfuric acid and of alcohol present in a given reaction The alcohols were for the most part the best mixture are known, the amount of acid which obtainable commercial products which were then would be present in 1 g. of reaction mixture, had dried and fractionated ...
... Calculations.-Since the weights of sulfuric acid and of alcohol present in a given reaction The alcohols were for the most part the best mixture are known, the amount of acid which obtainable commercial products which were then would be present in 1 g. of reaction mixture, had dried and fractionated ...
Chap20 Grignard reagents
... BH 3 : Adds to alkenes and alkynes (reducing them) With the CBS Catalyst, reduces ketones to alcohols, enantioselectively Selectively reduces carboxylic acids to alcohols (Does react with esters) NaBH 4 : Reduces aldehydes, acid chlorides, and ketones to the corresponding alcohol (reduces esters ver ...
... BH 3 : Adds to alkenes and alkynes (reducing them) With the CBS Catalyst, reduces ketones to alcohols, enantioselectively Selectively reduces carboxylic acids to alcohols (Does react with esters) NaBH 4 : Reduces aldehydes, acid chlorides, and ketones to the corresponding alcohol (reduces esters ver ...
Reduction of Aldehydes and Ketones
... Benedict’s Test Benedict’s test • gives a positive result with compounds that have an aldehyde functional group and an adjacent hydroxyl group. • utilizes Benedict’s solution, which contains Cu2+ (CuSO4). When the solution is added to this type of aldehyde and heated, a brick-red solid of Cu2O form ...
... Benedict’s Test Benedict’s test • gives a positive result with compounds that have an aldehyde functional group and an adjacent hydroxyl group. • utilizes Benedict’s solution, which contains Cu2+ (CuSO4). When the solution is added to this type of aldehyde and heated, a brick-red solid of Cu2O form ...
Biocatalytic reductions: From lab curiosity to “first choice”
... enantioselectivity, (iii) acting in mild aqueous conditions, (iv) low catalyst costs, or (v) versatility. The substrate spectrum of all alcohol dehydrogenases reported in the literature is broad enough to claim that almost every target ketone or aldehyde substrate can be converted to the correspondi ...
... enantioselectivity, (iii) acting in mild aqueous conditions, (iv) low catalyst costs, or (v) versatility. The substrate spectrum of all alcohol dehydrogenases reported in the literature is broad enough to claim that almost every target ketone or aldehyde substrate can be converted to the correspondi ...
Instructor notes
... “Shilov Chemistry” has focused on determining the mechanism of the original Shilov system. Shilov proposed a reasonable mechanism just a few years after the discovery of this system. The first step of this cycle involves the formation of a methylplatinum(II) intermediate by reaction of Pt(II) with m ...
... “Shilov Chemistry” has focused on determining the mechanism of the original Shilov system. Shilov proposed a reasonable mechanism just a few years after the discovery of this system. The first step of this cycle involves the formation of a methylplatinum(II) intermediate by reaction of Pt(II) with m ...
All Chemistry Formulas for O levels Chemistry by Ethan Wu
... Combustion Alkane + oxygen -> carbon dioxide + water vapour Substitution (under ultraviolet light) E.g. methane + chlorine -> chloromethane + hydrogen chloride Alkenes Combustion Alkene + oxygen -> carbon dioxide + water vapour As alkenes have higher percentage of carbon than alkanes, alkenes will b ...
... Combustion Alkane + oxygen -> carbon dioxide + water vapour Substitution (under ultraviolet light) E.g. methane + chlorine -> chloromethane + hydrogen chloride Alkenes Combustion Alkene + oxygen -> carbon dioxide + water vapour As alkenes have higher percentage of carbon than alkanes, alkenes will b ...
Aromatic nitro compounds Background Nomenclature
... (iii) Reduction in neutral medium: zinc dust and ammonium chloride convert nitro benzene to corresponding hydroxylamine. ...
... (iii) Reduction in neutral medium: zinc dust and ammonium chloride convert nitro benzene to corresponding hydroxylamine. ...
A Facile and Environmentally Friendly Disposal of Sodium and
... is a common drying agent for many solvents such as ethers, tertiary amines, and hydrocarbons. After the drying process large amounts of sodium remain, and these residues have to be destroyed. The best method so far is the addition of 2-propanol to the sodium waste. Accidents occur when the water con ...
... is a common drying agent for many solvents such as ethers, tertiary amines, and hydrocarbons. After the drying process large amounts of sodium remain, and these residues have to be destroyed. The best method so far is the addition of 2-propanol to the sodium waste. Accidents occur when the water con ...
Chapter 17 Allylic and Benzylic Reactivity
... Although the conjugate-base anion of 1,4-pentadiene is doubly allylic and resonance-stabilized, the conjugate-base anion of 1,3-cyclopentadiene is in addition aromatic. (See text p. 726 for a discussion of this case.) Consequently, much less energy is required for the ionization of 1,3-cyclopentadie ...
... Although the conjugate-base anion of 1,4-pentadiene is doubly allylic and resonance-stabilized, the conjugate-base anion of 1,3-cyclopentadiene is in addition aromatic. (See text p. 726 for a discussion of this case.) Consequently, much less energy is required for the ionization of 1,3-cyclopentadie ...
Lab #1: Borneol Oxidation
... recitation. However, if you want to get out of lab earlier, you should try to get as much of the prelab prep work done before you come to lab. You are expected to read this lab handout before going to lab and to read about alcohol oxidation in a textbook or online. Then you should prepare as much of ...
... recitation. However, if you want to get out of lab earlier, you should try to get as much of the prelab prep work done before you come to lab. You are expected to read this lab handout before going to lab and to read about alcohol oxidation in a textbook or online. Then you should prepare as much of ...
Document
... The reaction of methane (CH4) with chlorine in the presence of sunlight proceeds via a radical chain reaction. The overall equation for the reaction is equation (1) above. Complete the reaction mechanism below: ...
... The reaction of methane (CH4) with chlorine in the presence of sunlight proceeds via a radical chain reaction. The overall equation for the reaction is equation (1) above. Complete the reaction mechanism below: ...
Grant MacEwan College - Faculty Web Pages
... - reactions with compounds containing acidic hydrogen atoms - reactions of Grignard reagents with epoxides - reactions of Grignard reagents with carbonyl compounds Alcohols from Grignard Reagents How to plan a Grignard synthesis Restrictions on the use of Grignard reagents The use of lithium reagent ...
... - reactions with compounds containing acidic hydrogen atoms - reactions of Grignard reagents with epoxides - reactions of Grignard reagents with carbonyl compounds Alcohols from Grignard Reagents How to plan a Grignard synthesis Restrictions on the use of Grignard reagents The use of lithium reagent ...
Sublimation apparatus
... sublimation tube is securely held in position by the O-ring around the tube. The O-ring must be on the inside of the apparatus just below the threads of the multipurpose adapter in order to get a good seal (see Figure 17.2A)! Adjust the tube so that bottom of the tube is about 1 cm above the solid i ...
... sublimation tube is securely held in position by the O-ring around the tube. The O-ring must be on the inside of the apparatus just below the threads of the multipurpose adapter in order to get a good seal (see Figure 17.2A)! Adjust the tube so that bottom of the tube is about 1 cm above the solid i ...
Amines - ChemConnections
... Effect is Cumulative • Aniline is 3800 times more basic than p-nitroaniline. • Aniline is ~1,000,000,000 times more basic than 2,4-dinitroaniline. ...
... Effect is Cumulative • Aniline is 3800 times more basic than p-nitroaniline. • Aniline is ~1,000,000,000 times more basic than 2,4-dinitroaniline. ...
alkene structure, naming, stereochemistry & preparation
... [7.8] Macroscopic physical properties of alkenes - Lower alkenes (C2 to C5) are gases @ R.T. - Boiling point increases with C- number - Boiling point within the same size alkenes decreases with branching (same as alkanes) - Less dense than water (Gulf oil slick!); mixes poorly or not at all with wa ...
... [7.8] Macroscopic physical properties of alkenes - Lower alkenes (C2 to C5) are gases @ R.T. - Boiling point increases with C- number - Boiling point within the same size alkenes decreases with branching (same as alkanes) - Less dense than water (Gulf oil slick!); mixes poorly or not at all with wa ...
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... calculations have provided a better understanding of the reaction pathways in some catalytic systems.17 Some catalysts have shown very high reactivities.10a, 12b, 18 However, this reaction typically requires high temperature (>100 oC) and there are only a few reported examples of the reaction at low ...
... calculations have provided a better understanding of the reaction pathways in some catalytic systems.17 Some catalysts have shown very high reactivities.10a, 12b, 18 However, this reaction typically requires high temperature (>100 oC) and there are only a few reported examples of the reaction at low ...
Stockholm University
... 7), are tolerated under the applied reaction conditions. The reactions involving substituted allylacetates provide the branched products with very high regioselectivity. The diastereoselectivity of the reaction is also very high. In many cases a single diastereomer was obtained (Entries 2, 6, 7 and ...
... 7), are tolerated under the applied reaction conditions. The reactions involving substituted allylacetates provide the branched products with very high regioselectivity. The diastereoselectivity of the reaction is also very high. In many cases a single diastereomer was obtained (Entries 2, 6, 7 and ...
Alcohols - WordPress.com
... Alcohols are weak Brønsted bases Protonated by strong acids to yield oxonium ions, ...
... Alcohols are weak Brønsted bases Protonated by strong acids to yield oxonium ions, ...
ALDEHYDES AND KETONES:
... there is little tendency for methane to ionize to form a proton at the ion –CH3 in which carbon bears –ve charge. Such anions are called carbanions. ...
... there is little tendency for methane to ionize to form a proton at the ion –CH3 in which carbon bears –ve charge. Such anions are called carbanions. ...
Wolff–Kishner reduction
The Wolff–Kishner reduction is a reaction used in organic chemistry to convert carbonyl functionalities into methylene groups. In the context of complex molecule synthesis, it is most frequently employed to remove a carbonyl group after it has served its synthetic purpose of activating an intermediate in a preceding step. As such, there is no obvious retron for this reaction. Originally reported by Nikolai Kischner in 1911 and Ludwig Wolff in 1912, it has been applied to the total synthesis of scopadulcic acid B, aspidospermidine and dysidiolide.In general, the reaction mechanism first involves the in situ generation of a hydrazone by condensation of hydrazine with the ketone or aldehyde substrate. Sometimes it is however advantageous to use a pre-formed hydrazone as substrate (see modifications). The hydrazone is deprotonated by alkoxide base followed by a concerted, rate-determining step in which a diimide anion is formed. Collapse of this alkyldiimde with loss of N2 leads to formation of an alkylanion which can be protonated by solvent to give the desired product.Because the Wolff–Kishner reduction requires highly basic conditions, it is unsuitable for base-sensitive substrates. However, this method can be superior over the related Clemmensen reduction for acid-sensitive compounds such as pyrroles and for high-molecular weight compounds.