Concept explainers
The synthesis of cyclobutanecarboxylic acid given in Section 18.7 was first carried out by William Perkin, Jr., in 1883, and it represent-ed one of the first syntheses of an organic compound with a ring smaller than six carbon atoms. (There was a general feeling at the time that such compounds would be too unstable to exist.) Earlier in 1883, Perkin reported what he mistakenly believed to be a cyclobutane derivative obtained from the reaction of acetoacetic ester and 1,3-dibromopropane. The reaction that Perkin had expected to take place was the following:
The molecular formula for his product agreed with the formulation given in the preceding reaction, and alkaline hydrolysis and acidification gave a nicely crystalline acid (also having the expected molecular formula). The acid, however, was quite stable to heat and resisted decarboxylation. Perkin later found that both the ester and the acid contained six-membered rings (five carbon atoms and one oxygen atom). Recall the charge distribution in the enolate ion obtained from acetoacetic ester and propose structures for Perkin’s ester and acid.
Want to see the full answer?
Check out a sample textbook solutionChapter 18 Solutions
EBK ORGANIC CHEMISTRY
Additional Science Textbook Solutions
Chemistry: A Molecular Approach
General, Organic, and Biological Chemistry: Structures of Life (5th Edition)
Organic Chemistry As a Second Language: Second Semester Topics
Chemistry: The Central Science (14th Edition)
Chemistry & Chemical Reactivity
Introductory Chemistry (6th Edition)
- Vanillic acid is the oxidized phenolic derivative of vanillin. By using Proton Nuclear Magnetic Resonance ('H-NMR) spectroscopic technique, point out the difference that can be observed between vanillin and vanillic acid in terms of chemical shift based on its chemical structures. но Он Vanillic acid Vanillinarrow_forwardFor following substituted benzenes: [1] C6H5Br; [2] C6H5CN; [3] C6H5OCOCH3: Does the substituent activate or deactivate the benzene ring inelectrophilic aromatic substitution?arrow_forwardEnanthotoxin is an extremely poisonous organic compound found in hemlock water drop- wart, which is reputed to be the most poisonous plant in England. It is believed that no British plant has been responsible for more fatal accidents. The most poisonous part of the plant is the roots, which resemble small white carrots, giving the plant the name"five finger death."Also poisonous are its leaves, which look like parsley. Enanthotoxin is thought to interfere with the Nat current in nerve cells, which leads to convulsions and death. он How many stereoisomers are possible for enanthotoxin?arrow_forward
- An aromatic hydrocarbon with a molecular formula of C13H20 has an 1H NMR spectrum with a signal at ~7 ppm that integrates to 5H. It also has two singlets; one of the singlets has 1.5 times the area of the second. What is the structure of the aromatic hydrocarbon?arrow_forwardThe hydrocarbon fluorene was treated with potassium t-butoxide in an acid-base reaction, giving the fluorenide anion and t-butyl alcohol. (a) Which way does the equilibrium lie, and by how much? b) What is the proportion of the fluorenide anion to fluorene? (c) Why is fluorene so highly acidic, considering the pKa of an average alkane is above 50?arrow_forwardFor the following monosubstituted benzenes, (a) determine whether the group is strongly, moderately, or weakly activating or deactivating, (b) write the three possible products for the reaction, and (c) predict which of these three products you would expect to predominatearrow_forward
- This is an organic chemistry question. PLEASE SHOW STEP BY STEP! ALSO PLEASE INCLUDE ALL ELECTRON LONE PAIRS AND CHARGES FOR STRUCTURES IF NECESSARY! Make sure you include a detailed explanation of your answer.arrow_forward(a) Tsomane and Nyiko were given a task of synthesising methylenecyclohexane 2. After a brief discussion with each other, Tsomane proposed Method A to synthesise 2 from cyclohexanone 1 while Nyiko proposed Method B that started from hydroxymethylcyclohexane 3. Each student believed that their proposed method is better than the other. (Scheme below) Ph THF A Ph Ph B H₂SO4 100 °C 3 OH (iii) In analysing both these methods, are there other possible alkene products other than methylenecyclohexane 2? Use mechanistic details to support your answer.arrow_forwardBenzoic acid, Ph-COOH (C6H5CO2H), is not soluble in water while it dissolves in ether (diethyl ether), (CH3CH2)2O. Yet upon treatment with sodium hydroxide, benzoic acid turns hydrophilic and dissolves in water. Provide chemical explanation of this observation.arrow_forward
- (a) Tsomane and Nyiko were given a task of synthesising methylenecyclohexane 2. After a brief discussion with each other, Tsomane proposed Method A to synthesise 2 from cyclohexanone 1 while Nyiko proposed Method B that started from hydroxymethylcyclohexane 3. Each student believed that their proposed method is better than the other. (Scheme below) (1) Ph Ph 8*8 Ph THF A 1 Santande B H₂SO4 100 °C 3 OH Using curly arrows, provide full mechanistic details accounting how methylenecyclohexane 2 was synthesised according to both Methods A and B.arrow_forwardGg.108.arrow_forward(a) Which is more reactive towards Electrophilic aromatic substitution (EAS)? (b) Which of the following is a a meta-substituted compound? (c) Which is the least reactive towards Electrophilic aromatic substitution (EAS)? (d) Which is an ortho-substituted compound?arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning