Download Organic Chemistry Reactions of Alcohols and more Exams Chemistry in PDF only on Docsity! Organic Chemistry 1 Midterm Exam #4 Questions with Answers Latest Update What are the types of alcohol reactions you need to know? - Correct Answers 1. dehydration into an alkene 2. oxidation into an aldehyde or ketone 3. substitution to form an alkyl halide 4. reduction into an alkane 5. esterification 6. tosylation 7. Williamson synthesis of ethers reaction of alcohols: dehydration into an alkene - Correct Answers reaction of alcohols: oxidation into an aldehyde or ketone - Correct Answers oxidation of secondary alcohols: - becomes a ketone - color change from orange to greenish-blue oxidation of primary alcohols: - becomes an aldehyde, the can get oxidized a second time to become carboxylic acid (hard to prevent that second oxidation, but use PCC to stop after just the 1st) + PCC can also oxidize secondary alcohols into ketones !!! tertiary alcohols don't oxidize because they can't lose a oxidation - Correct Answers loss of H2 gain of O, O2 or X2 other oxidation reagents - Correct Answers • Collins reagent: Cr2O3 in pyridine • Jones reagent: chromic acid in acetone • KMnO4 (strong oxidizer) • Nitric acid (strong oxidizer) • Cu, 300°C (industrial dehydrogenation) • Sworn oxidation: dimethylsulfoxide, with orally chloride and hindered base, oxidizes secondary alcohols to ketones and primary alcohols to aldehydes. biological oxidation - Correct Answers • Catalyzed by ADH, alcohol dehydrogenase. • Oxidizing agent is NAD+, nicotinamide adenine dinucleotide. • Ethanol oxidizes to acetaldehyde, then acetic acid, a normal metabolite. • Methanol oxidizes to formaldehyde, then formic acid, more toxic than methanol. • Ethylene glycol oxidizes to oxalic acid, toxic. • Treatment for poisoning is excess ethanol. reaction of alcohols: substitution to form an alkyl halide - Correct Answers reaction of alcohols: reduction into an alkane - Correct Answers - alcohol to alkene: dehydrate with concentrated H2SO4 + alkene to alkane: H2 / Pt. - alcohol to tosylate: Tesco + tosylate to alkane: LAH --> just follow the image from secondary alcohol to alkene to alkane + alcohol to tosylate to alkane reduction - Correct Answers gain of H2 or H- loss of O, O2, or X2 neither oxidation nor reduction - Correct Answers gain or loss of H+, H2O, or HX oxidative-ness and reductive-ness of primary, secondary, and tertiary carbons - Correct Answers alkanes, with no bonds to oxygen, are very reductive and hardly oxidative carboxylic acids, with 3 bonds to oxygen, are very oxidative and hardly reductive increasing the bonds you have to oxygen increases how oxidative the a molecule is reaction of alcohols: esterification - Correct Answers reaction of alcohols: tosylation - Correct Answers how do you reduce alcohols (into alkanes)? - Correct Answers 1. dehydrate with concentrated H2SO4, and then add H2 2. tosylate, then reduce with LiAlH4 formation of tosylate ester - Correct Answers Tesco with pyridine + alcohol OTs takes place of OH, better leaving group (good electrophile) SN2 Reactions of Tosylates, aka Tosylate Esters - Correct Answers • With hydroxide produces alcohol • With cyanide produces nitrile
