Low-valent titanium: New synthetic applications
... In our attempts to exrend the above protocol ro the synthesis of 2.3-dialkylbenzo[b]luram. i: n a s logical to use 2'-acetoxyacetophenone (5) as substrate. To our surprise, 2.3-dimerhylbenzo[b]furan ( 6 ) was not formed hut diarylalkane (9: R=H) was obtained as the major product along with minor amo ...
... In our attempts to exrend the above protocol ro the synthesis of 2.3-dialkylbenzo[b]luram. i: n a s logical to use 2'-acetoxyacetophenone (5) as substrate. To our surprise, 2.3-dimerhylbenzo[b]furan ( 6 ) was not formed hut diarylalkane (9: R=H) was obtained as the major product along with minor amo ...
Carbon-Carbon Bond Formation by Reductive Coupling with
... ometry of reaction and the formation of tetrachlorodititanoxane(III) 6. b) Scope o f organic substrates reducible by 1 (Table I) a) Hydrocarbons: Although titanium (II) chlo ride in the form of complexes 1, 2 and 3 and ad mixed with a six to eight-fold excess of M e2AlCl is able to catalyze the po ...
... ometry of reaction and the formation of tetrachlorodititanoxane(III) 6. b) Scope o f organic substrates reducible by 1 (Table I) a) Hydrocarbons: Although titanium (II) chlo ride in the form of complexes 1, 2 and 3 and ad mixed with a six to eight-fold excess of M e2AlCl is able to catalyze the po ...
document
... Sterics: more crowding, less stable The greater number of attached alkyl groups or the more highly substituted the carbon atoms of the double bond, the greater is the alkene’s stability ...
... Sterics: more crowding, less stable The greater number of attached alkyl groups or the more highly substituted the carbon atoms of the double bond, the greater is the alkene’s stability ...
Halogenoalkanes
... Note that this reaction is very exothermic so the solution must be cold, or dry ice (solid CO2 at –78o C used instead). ...
... Note that this reaction is very exothermic so the solution must be cold, or dry ice (solid CO2 at –78o C used instead). ...
CH 12-3 Power Point
... •Important multi-step synthesis for making new C-C bonds, and 1o, 2o, and 3o alcohols. ...
... •Important multi-step synthesis for making new C-C bonds, and 1o, 2o, and 3o alcohols. ...
Lecture 6
... An alkene and a hydride usually react via migration of the hydride to the coordinated alkene ligand. ligand The reverse reaction is called a β-elimination β elimination and is favored in the presence of an empty metal orbital cis to the alkyl ligand ...
... An alkene and a hydride usually react via migration of the hydride to the coordinated alkene ligand. ligand The reverse reaction is called a β-elimination β elimination and is favored in the presence of an empty metal orbital cis to the alkyl ligand ...
MAIN GROUP ORGANOMETALLICS Dr. S. Draper 8 lecture course
... in the low volatility and insolubility of (LiCH3)4 in nonsolvating media. The structure of t butyl lithium is similar but the intermolecular forces are weaker and hence tBuLi is soluble in hydrocarbons and sublimes at 70o C/1 mbar. Coordinating solvents will tend to give monomeric or dimeric species ...
... in the low volatility and insolubility of (LiCH3)4 in nonsolvating media. The structure of t butyl lithium is similar but the intermolecular forces are weaker and hence tBuLi is soluble in hydrocarbons and sublimes at 70o C/1 mbar. Coordinating solvents will tend to give monomeric or dimeric species ...
Palladium(II)-catalyzed Suzuki–Miyaura Reactions of Arylboronic
... phosphine (cat. 5)) ligands with palladium salts as precursors in Suzuki–Miyaura reaction. Suzuki–Miyaura reaction is one of the important cross-coupling reactions and extremely powerful in forming C–C bonds. Aryl-ferrocenyl-phosphine ligands confer unprecedented activity for these processes, allowi ...
... phosphine (cat. 5)) ligands with palladium salts as precursors in Suzuki–Miyaura reaction. Suzuki–Miyaura reaction is one of the important cross-coupling reactions and extremely powerful in forming C–C bonds. Aryl-ferrocenyl-phosphine ligands confer unprecedented activity for these processes, allowi ...
Notes on Substitutions and Eliminations
... base and is not as good as a leaving group. 3. The nucleophile – this is the Lewis Base that goes after the substrate, either to replace the leaving group in a substitution reaction or that removes a proton to create a double bond in an elimination reaction. Any Lewis base can be a nucleophile, the ...
... base and is not as good as a leaving group. 3. The nucleophile – this is the Lewis Base that goes after the substrate, either to replace the leaving group in a substitution reaction or that removes a proton to create a double bond in an elimination reaction. Any Lewis base can be a nucleophile, the ...
Chapter 7 Alkenes and Alkynes I
... Syn Addition of Hydrogen: Synthesis of cis-Alkenes The P-2 catalyst nickel boride results in syn addition of one equivalent of hydrogen to a triple bond An internal alkyne will yield a cis double bond ...
... Syn Addition of Hydrogen: Synthesis of cis-Alkenes The P-2 catalyst nickel boride results in syn addition of one equivalent of hydrogen to a triple bond An internal alkyne will yield a cis double bond ...
Elimination Reactions
... In addition to substitution, alkyl halides can also undergo elimination reactions, which lead to the formation of alkenes. As with substitution reactions, elimination reactions come in two mechanistic types: E1 eliminations (a two-step process involving an intermediate carbocation) E2 eliminations ( ...
... In addition to substitution, alkyl halides can also undergo elimination reactions, which lead to the formation of alkenes. As with substitution reactions, elimination reactions come in two mechanistic types: E1 eliminations (a two-step process involving an intermediate carbocation) E2 eliminations ( ...
Chem 30B Spring 2004 QUIZ #1 KEY Weds April 14th / 30
... BONUS QUESTION: What is the product of the Pinacol rearrangement shown below? Write your answer (just the structure) clearly in the box provided on the cover sheet to this quiz. There will be NO partial credit – either your structure is right or wrong. The next blank page can be used for working thr ...
... BONUS QUESTION: What is the product of the Pinacol rearrangement shown below? Write your answer (just the structure) clearly in the box provided on the cover sheet to this quiz. There will be NO partial credit – either your structure is right or wrong. The next blank page can be used for working thr ...
A-level Paper 2 Practice Paper 1 - A
... A simple test-tube reaction can be used to distinguish between isomer Q and all the other isomers. Identify a reagent (or combination of reagents) you could use. State what you would observe when Q is tested with this reagent or combination of reagents. ...
... A simple test-tube reaction can be used to distinguish between isomer Q and all the other isomers. Identify a reagent (or combination of reagents) you could use. State what you would observe when Q is tested with this reagent or combination of reagents. ...
Taylor`s Organic Reactions Summary Sheet
... Alcohols Alcohols are formed by addition reactions between an Alkene/Alkyne and water this is called a hydration reaction. The hydrogen attaches to the carbon atom that already has more hydrogen atoms; the –OH group attaches to the other carbon atom in the double bond. Hydration Reaction: A reaction ...
... Alcohols Alcohols are formed by addition reactions between an Alkene/Alkyne and water this is called a hydration reaction. The hydrogen attaches to the carbon atom that already has more hydrogen atoms; the –OH group attaches to the other carbon atom in the double bond. Hydration Reaction: A reaction ...
Development of a Greener Selective Acylation Method for Steroids
... The reaction using dichloromethane as a solvent was complete on adding the catalyst to the reaction mixture. When ethyl acetate was used as a solvent, the starting material was not completely used up (Figure 2). Both reactions led to the formation of a product with the same retention time of the ref ...
... The reaction using dichloromethane as a solvent was complete on adding the catalyst to the reaction mixture. When ethyl acetate was used as a solvent, the starting material was not completely used up (Figure 2). Both reactions led to the formation of a product with the same retention time of the ref ...
Chemistry Final Test
... Which of the following statements is correct regarding this reaction? (A) This reaction is a nucleophilic reaction. (B) This reaction is a substitution reaction. (C) A negatively charged intermediate is involved in this reaction. (D) A cyclic bromonium ion is an intermediate in this reaction. 6-2、Wh ...
... Which of the following statements is correct regarding this reaction? (A) This reaction is a nucleophilic reaction. (B) This reaction is a substitution reaction. (C) A negatively charged intermediate is involved in this reaction. (D) A cyclic bromonium ion is an intermediate in this reaction. 6-2、Wh ...
Slides
... Basis of Zaitsev’s Rule: Transition state has double bond character t T.S. reflects greater stability of more substituted double bond ...
... Basis of Zaitsev’s Rule: Transition state has double bond character t T.S. reflects greater stability of more substituted double bond ...
Nugget
... involving fully characterized mononuclear Ru(II) complexes, with overall retention of the metal oxidation state, has been demonstrated; O-O bond formation is intramolecular and involves a single metal center. Science 2009, 324, 74 ...
... involving fully characterized mononuclear Ru(II) complexes, with overall retention of the metal oxidation state, has been demonstrated; O-O bond formation is intramolecular and involves a single metal center. Science 2009, 324, 74 ...
CHEM 203 Topics Discussed on Nov. 20 Principle: protonation of
... Principle: the above reagents rely on the nucleophilic properties of the OH group to achieve conversion of alcohols into alkyl halides Principle: only primary and secondary alcohols are sufficiently nucleophilic to react with the above reagents. The OH group of tertiary alcohols is poorly nucleophil ...
... Principle: the above reagents rely on the nucleophilic properties of the OH group to achieve conversion of alcohols into alkyl halides Principle: only primary and secondary alcohols are sufficiently nucleophilic to react with the above reagents. The OH group of tertiary alcohols is poorly nucleophil ...
Workshop 9
... Reactions of Alcohols, Ethers, and Epoxides Writing Reaction Mechanisms. A reaction mechanism is a detailed description of the way a reaction occurs and is based on the known experimental data about the reaction. Some reaction mechanisms are well established. In other cases they may be speculative a ...
... Reactions of Alcohols, Ethers, and Epoxides Writing Reaction Mechanisms. A reaction mechanism is a detailed description of the way a reaction occurs and is based on the known experimental data about the reaction. Some reaction mechanisms are well established. In other cases they may be speculative a ...
Student Instructions from Laboratory Manual
... bar. With vigorous stirring, slowly add 2.5 equiv of lithium triethylborohydride [aka, SuperHydride®] (1.0-M solution in THF) by syringe, cap the flask, and allow the reaction to proceed for 20 min. Add 3 equiv of methyl iodide slowly by calibrated micropipette and stir the resulting reaction mixtur ...
... bar. With vigorous stirring, slowly add 2.5 equiv of lithium triethylborohydride [aka, SuperHydride®] (1.0-M solution in THF) by syringe, cap the flask, and allow the reaction to proceed for 20 min. Add 3 equiv of methyl iodide slowly by calibrated micropipette and stir the resulting reaction mixtur ...
synthesis in industry
... give very low yields of the desired 2-alkyl-3-chloronaphthoquinones. Dialkylation and reduction of the quinone are major complications. Mild alkylating agents such as tetraalkyltins do not react with the dichloro compound unassisted, but we found that the alkylation can be catalyzed. For example, th ...
... give very low yields of the desired 2-alkyl-3-chloronaphthoquinones. Dialkylation and reduction of the quinone are major complications. Mild alkylating agents such as tetraalkyltins do not react with the dichloro compound unassisted, but we found that the alkylation can be catalyzed. For example, th ...
VG-Catalytic Conversion of Bio
... upgrading of bio-ethanol towards chemicals. Zeolites are known to be hydrothermal stable catalysts at elevated temperatures and selective for the production of these hydrocarbons from alcohols. However, future catalyst and process improvements can be hampered by the lack of insight in the reaction m ...
... upgrading of bio-ethanol towards chemicals. Zeolites are known to be hydrothermal stable catalysts at elevated temperatures and selective for the production of these hydrocarbons from alcohols. However, future catalyst and process improvements can be hampered by the lack of insight in the reaction m ...
Stille reaction
The Stille reaction, or the Migita-Kosugi-Stille coupling, is a chemical reaction widely used in organic synthesis which involves the coupling of an organotin compound (also known as organostannanes) with a variety of organic electrophiles via palladium-catalyzed coupling reaction.The R1 group attached to the trialkyltin is normally sp2-hybridized, including alkenes, and aryl groups; however, conditions have been devised to incorporate both sp3-hybridized groups, such as allylic and benzylic substituents, and sp-hybridized alkynes. These organostannanes are also stable to both air and moisture, and many of these reagents are either commercially available or can be synthesized from literature precedent. However, these tin reagents tend to be highly toxic. X is typically a halide, such as Cl, Br, I, yet pseudohalides such as triflates and sulfonates and phosphates can also be used.The groundwork for the Stille reaction was laid by Colin Eaborn, Toshihiko Migita, and Masanori Kosugi in 1976 and 1977, who explored numerous palladium catalyzed couplings involving organotin reagents. John Stille and David Milstein developed a much milder and more broadly applicable procedure in 1978. Stille’s work on this area might have earned him a share of the 2010 Nobel Prize, which was awarded to Richard Heck, Ei-ichi Negishi, and Akira Suzuki for their work on the Heck, Negishi, and Suzuki coupling reactions. However, Stille died in the plane crash of United Airlines Flight 232 in 1989.Several reviews have been published on the Stille reaction.