Concept explainers
Open the molecular model file for benzyne and examine the following molecular orbitals: the LUMO (lowest unoccupied molecular orbital), the HOMO (highest occupied molecular orbital), the HOMO-1 (next lower energy orbital), the HOMO-2 (next lower in energy), and the HOMO-3 (next lower in energy).
(a) Which orbital best represents the region where electrons of the additional πp bond in benzyne would be found?
(b) Which orbital would accept electrons from a Lewis base on nucleophilic addition to benzyne?
(c) Which orbitals are associated with the six
Want to see the full answer?
Check out a sample textbook solutionChapter 15 Solutions
Organic Chemistry
Additional Science Textbook Solutions
Chemistry: An Introduction to General, Organic, and Biological Chemistry (12th Edition) - Standalone book
Chemistry & Chemical Reactivity
Introductory Chemistry (5th Edition) (Standalone Book)
Organic Chemistry
Chemistry: Structure and Properties (2nd Edition)
Chemistry: A Molecular Approach (4th Edition)
- The enamine prepared from acetone and dimethylamine is shown here in its lowest-energy form. (a) What is the geometry and hybridization of the nitrogen atom? (b) What orbital on nitrogen holds the lone pair of electrons? (c) What is the geometric relationship between the p orbitals of the double bond and the nitrogen orbital that holds the lone pair? Why do you think this geometry represents the minimum energy?arrow_forward(a) Draw the molecular orbital picture for propa-1,2-diene, H2C=C=CH2. Hint: The three-dimensional geometry is shownin the chapter. (b) Draw the MO energy diagram for propa-1,2-diene. What is the HOMO? What is the LUMO?arrow_forwardAzulene, an isomer of naphthalene, has a remarkably large dipole moment for a hydrocarbon (μ = 1.0 D). Explain, using resonance structures.arrow_forward
- How many rings and π bonds are contained in a compound of molecularformula C8H12 that is hydrogenated to a compound of molecular formulaC8H14?arrow_forward4. Explain why the protons on the sp³-hybridized carbon of propene (CH3-CH=CH₂) are more acidic than the protons on the sp²-hybridized carbons of propene, even though sp2-hybridized carbons are more electronegative than sp³-hybridized carbons. Use both structures and sentences in your answer.arrow_forward(a) What orbitals are used to form the indicated bonds in α-sinensal?(b) In what type of orbitals do the lone pairs on O reside?arrow_forward
- Consider 1-bromopropane, CH3CH2CH2Br. (a) Draw a Newman projection for the conformation in which CH3 and -Br are anti (dihedral angle 180°). (b) Draw Newman projections for the conformations in which - CH3 and -Br are gauche (dihedral angles 60° and 300°). (c) Which of these is the lowest energy conformation? (d) Which of these conformations, if any, are related by reflection?arrow_forwardRank the following set of compounds in order of increasing bond λmax.arrow_forwardWhich compoundshave zero dipole moments?(a) cis-1,2-dichloroethene or cis-1,2-dibromoethenearrow_forward
- For each pair of compounds, predict which one has the higher molecular dipole moment, and explain your reasoning.(a) cis-2,3-dibromobut-2-ene or trans-2,3-dibromobut-2-enearrow_forward(b) Consider Scheme Q21b: (i) OH im i base Scheme Q21b E What type of reaction is taking place that convert D to E? (ii) Redraw structure E then circle the substituents on the double assign priorities according to the Cahn-Ingold-Prelog rules. (iii) Derive the IUPAC name of structure E.arrow_forwardThe figure below represents the highest accupied molecular orbitals (HOMOS) and the lowest unoccupied molecular orbital (LUMO) for an organic compound with a ketone functional group. The and n orbitals represent the HOMOS and the a* represents the LUMO orbital. л" E I Nonpolar solvent I* Л Polar solvent To The left side HOMOS and LUMO represent the molecule in a nonpolar solvent, and the right side represent the HOMOS and LUMD in a polar solvent, such as water. You can see the change in the energy of the HOMOS and LUMO when the polar solvent interacts with the electrons in the ann orbitals. Study the figure and choose which of the following statements are true or false about why there is a blue shift in the electronic transition. Select all that are True. the energy gap between the n MO and the n* MO is larger in the polar solvent than in the nonpolar solvent, so the photon needed to excite the electron would require more energy when the molecule is in the polar solvent the energy gap…arrow_forward