Concept explainers
Interpretation:
The reason behind hydrogens attached to third carbon in 1,4-pentadiene being more susceptible to abstraction by radicals is to be explained. Also, the reason behind hydrogens attached to third carbon in 1,4-pentadiene being more acidic than hydrogens attached to methyl group of propene is to be explained.
Concept introduction:
舧 Electrophiles are electron-deficient species, which has positive or partially positive charge. Lewis acids are electrophiles, which accept electron pair.
舧 Nucleophiles are electron-rich species, which has negative or partially negative charge. Lewis bases are nucleophiles, which donate electron pair.
舧 Free radical is an atom, molecule, or ion that has an unpaired electron, which makes it highly chemically reactive.
舧 Conjugated systems consist of a phenomenon known as conjugation, which can be defined as an interaction between p-orbitals with another across an intervening sigma bond. Conjugated systems, in simple words, can be represented as a system in organic compounds having alternate double bonds and single bonds.
舧 Delocalization of unpaired electrons results in more stability. Alkyl groups attached to the carbon atom having the positive charge or radical, helps in more stabilization of charge. Thus, tertiary carbocations or radicals are more stable than secondary and secondary carbocations are more stable than primary carbocations or radicals.
舧 Resonance is having 2 different shapes of a chemical entity but the change is only in the electron pair positions.
舧 Resonance enhances the acidity of the compound and makes it easier for the compound to give up protons. Higher resonant structures increase acidity of the compound.
The rules for drawing resonance structures are as follows:
舧 Only non-bonding electron pairs and pi electrons can participate in conjugation in the formation of various resonating structures.
舧 The single bonds present in the molecule do not break or form in the resonance structures.
舧 The placement of atoms present in the molecule remains fixed.
舧 The octet of all atoms is completely filled.
舧 More the number of resonance structures indicate higher stability of a compound.
Want to see the full answer?
Check out a sample textbook solutionChapter 13 Solutions
Organic Chemistry
- Please tell the outcome of the addition of HBr to (a) trans-2-pentene, (b) 2-methyl-2-butene, and (c) 4-methylcyclohexene. Also please list how many isomers can be formed in each case.arrow_forwardMethyl acrylate (H2C=CHCO2CH3) reacts with 1,3-cyclopentadiene to give a mixture of two products. Write structural formulas for both and predict which one predominates.arrow_forwardBiphenyl has the following structure.(a) Is biphenyl a (fused) polynuclear aromatic hydrocarbon?(b) How many pi electrons are there in the two aromatic rings of biphenyl? How does this number compare with that for naphthalene?(c) The heat of hydrogenation for biphenyl is about 418 kJ>mol (100 kcal>mol). Calculate theresonance energy of biphenyl.(d) Compare the resonance energy of biphenyl with that of naphthalene and with that of two benzene rings. Explain thedifference in the resonance energies of naphthalene and biphenyl.arrow_forward
- (a) Chromic acid oxidation of 4-tert-butyl-1,2-dimethylbenzene yielded a single compound having the molecular formula C12H14O4. What was this compound?(b) What product is expected from chromic acid oxidation of 2,3-dihydroindene?arrow_forwardArrange the following compounds in increasing order of their property as indicated :(i) CH3COCH3, C6H5COCH3, CH3CHO(reactivity towards nucleophilic addition reaction)(ii) Cl—CH2—COOH, F—CH2—COOH, CH3—COOH (acidic character)arrow_forwardCalculate the units of unsaturation of C6H7NO. And draw out the structure.arrow_forward
- Help me pleasearrow_forwardThere are two alkenes that react with HBr to give 1-bromo-1-methylcyclohexane. Draw their structures.arrow_forwardCompound X (structure shown below) has a molecular formula C5H1o and reacts with H2/Pt to give compound Y, C5H12. What is the name of the reaction involved to produce Compound Y? H2C H3C CH3 Hydration Hydrogenation Halogenation Addition of halohydrinarrow_forward
- Compounds X and Y have the formula C6H12- Both X and Y react with one molar equivalent of hydrogen in the presence of a palladium catalyst to form 2-methylpentane. The heat of hydrogenation of X is less than that of Y. X and Y react with HBr to form a mixture of the same bromoalkanes, and they both undergo hydroboration/oxidation to give a mixture of the same alcohols. What is the structure of Y? In cases where there is more than one answer, just draw one. n. n [ ]# ChemDoodleⓇ zaarrow_forwardA hydrocarbon C5H12 gives only one mono-chlorination product. Identify the hydrocarbon.arrow_forward5B In the following reactions, mixtures of alkenes and ethyl ethers are formed. Draw their structures. Explain which is or are likely to be the main product(s) in each reaction. In case of formation of two isomers of alkenes, explain which is formed in greater proportion CH3 CH3 H3C-C H -Br CH3 EtOHarrow_forward
- ChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage LearningChemistryChemistryISBN:9781259911156Author:Raymond Chang Dr., Jason Overby ProfessorPublisher:McGraw-Hill EducationPrinciples of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning
- Organic ChemistryChemistryISBN:9780078021558Author:Janice Gorzynski Smith Dr.Publisher:McGraw-Hill EducationChemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage LearningElementary Principles of Chemical Processes, Bind...ChemistryISBN:9781118431221Author:Richard M. Felder, Ronald W. Rousseau, Lisa G. BullardPublisher:WILEY