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Chapter 12
Chapter 12

... OCH2CH3 CH3 C OCH2CH3 + H2O CH3 ...
+ Br2, FeBr3 + Br2, FeBr3
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... Epoxidations of alkenes with m-CPBA are usually carried out by mixing the reactants in CH2 Cl2 or CHCl3 at 0–25 ◦ C.9 After the reaction is complete the reaction mixture is cooled in an ice bath and the precipitated m-chlorobenzoic acid is removed by filtration. The organic layer is washed with sodi ...
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2009 Final Exam - Department of Chemistry | Oregon State University
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... Consider a "General Chemistry Battery" in which one beaker contains aqueous tin sulfate (SnSO4) and a tin metal electrode and the other beaker contains aqueous lead sulfate (PbSO4) and a lead metal electrode. Which of the following statements is false? (A) (B) (C) (D) ...
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Alcohols - WordPress.com
Alcohols - WordPress.com

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Chapter 12 Carboxylic Acids
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Chapter - FIU Faculty Websites

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Carbonyl Compounds I. Aldehydes and Ketones
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... the angle strain means that a sizable enhancement of both the reactivity and equilibrium constant for addition is expected. In practice, the strain effect is so large that cyclopropanone reacts rapidly with methanol to give a stable hemiketal from which the ketone cannot be recovered. Cyclobutanone ...
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... oxazolidinone auxiliary. There are several protocols for this, but just a couple will be given. Carbonyl Hydrolysis: The amide like carbonyl should be more susceptible to nucleophilic attack, than the carbamate carbonyl, so HO- should be able to hydrolyze this to a carboxylic acid. When it’s done, L ...
Ir-catalysed formation of C− F bonds. From allylic alcohols to α
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13. amines - WordPress.com
13. amines - WordPress.com

... Basicity of amines is related to their structure. Basic character of an amine depends upon the ease of formation of the cation by accepting a proton from the acid. As the stability of the cation increases, the basicity also increases. a) Comparison of basicity of alkyl amines (alkanamines) and ammon ...
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Wolff rearrangement



The Wolff rearrangement is a reaction in organic chemistry in which an α-diazocarbonyl compound is converted into a ketene by loss of dinitrogen with accompanying 1,2-rearrangement. The Wolff rearrangement yields a ketene as an intermediate product, which can undergo nucleophilic attack with weakly acidic nucleophiles such as water, alcohols, and amines, to generate carboxylic acid derivatives or undergo [2+2] cycloaddition reactions to form four-membered rings. The mechanism of the Wolff rearrangement has been the subject of debate since its first use. No single mechanism sufficiently describes the reaction, and there are often competing concerted and carbene-mediated pathways; for simplicity, only the textbook, concerted mechanism is shown below. The reaction was discovered by Ludwig Wolff in 1902. The Wolff rearrangement has great synthetic utility due to the accessibility of α-diazocarbonyl compounds, variety of reactions from the ketene intermediate, and stereochemical retention of the migrating group. However, the Wolff rearrangement has limitations due to the highly reactive nature of α-diazocarbonyl compounds, which can undergo a variety of competing reactions.The Wolff rearrangement can be induced via thermolysis, photolysis, or transition metal catalysis. In this last case, the reaction is sensitive to the transition metal; silver (I) oxide or other Ag(I) catalysts work well and are generally used. The Wolff rearrangement has been used in many total syntheses; the most common use is trapping the ketene intermediate with nucleophiles to form carboxylic acid derivatives. The Arndt-Eistert homologation is a specific example of this use, wherein a carboxylic acid may be elongated by a methylene unit. Another common use is in ring-contraction methods; if the α-diazo ketone is cyclic, the Wolff rearrangement results in a ring-contracted product. The Wolff rearrangement works well in generating ring-strained systems, where other reactions may fail.
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