Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Question
Chapter 30.1, Problem 1P
Interpretation Introduction
Interpretation:
HOMO and LUMO of ethylene and 1,3-butadiene for both ground and excited states.
Concept introduction:
The most important orbitals in molecules for reactivity are the two so called frontier orbitals. These are called the HOMO (highest occupied molecular orbital and LUMO (lowest unoccupied molecular orbital). The HOMO is the highest energy MO that has any electrons in it. Electrons from the HOMO are donated and mostly available for bonding. The LUMO is the next highest energy orbital (it will be empty). It is the lowest unoccupied molecular orbital which can receives electrons.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
5) Give a representation of the highest occupied л MO of 1,3-butadiene in its ground state
or each of the following molecules, construct the MOS
from the 2p, atomic orbitals perpendicular to the plane of
the carbon atoms.
(a) Cyclobutadiene HC=CH
НС—СН
HC=CH
НС —СH
(b) Allyl radical
H
H
H
H
C=C
•C-C,
H
C-H
H
C-H
H
H
Indicate which, if any, of these orbitals have identical ener-
gies from symmetry considerations. Show the number of
electrons occupying each w MO in the ground state, and
indicate whether either or both of the molecules are para-
magnetic. Assume that the C atoms in the allyl radical are
all sp? hybridized.
Activate
io to S
In the electron paramagnetic resonance spectrum ofthe propyl radical, C3H5, the hyperfine splitting constant is1.45 mT for coupl ing to the protons on the terminal carbonatoms and 0.406 mT for coupl ing to the protons attached tothe central carbon atom. Taking 0= 2.25 mT, use the McConnellequation to estimate the unpaired electron density on eachcarbon atom.
Chapter 30 Solutions
Organic Chemistry
Ch. 30.1 - Prob. 1PCh. 30.3 - Prob. 2PCh. 30.3 - Prob. 3PCh. 30.4 - Prob. 4PCh. 30.6 - What stereochemistry would you expect for the...Ch. 30.6 - Prob. 6PCh. 30.7 - Prob. 7PCh. 30.8 - Propose a mechanism to account for the fact that...Ch. 30.8 - When a 2, 6-disubstituted allyl phenyl ether is...Ch. 30.9 - Prob. 10P
Ch. 30.SE - Predict the product obtained when the following...Ch. 30.SE - Prob. 12VCCh. 30.SE - The following rearrangement of N-allyl-N,...Ch. 30.SE - Plastic photochromic sunglasses are based on the...Ch. 30.SE - Prob. 15MPCh. 30.SE - Prob. 16MPCh. 30.SE - Prob. 17MPCh. 30.SE - Prob. 18APCh. 30.SE - Prob. 19APCh. 30.SE - Prob. 20APCh. 30.SE - Prob. 21APCh. 30.SE - Prob. 22APCh. 30.SE - Prob. 23APCh. 30.SE - Prob. 24APCh. 30.SE - Prob. 25APCh. 30.SE - Prob. 26APCh. 30.SE - Prob. 27APCh. 30.SE - Prob. 28APCh. 30.SE - Propose a pericyclic mechanism to account for the...Ch. 30.SE - Prob. 30APCh. 30.SE - Prob. 31APCh. 30.SE - Prob. 32APCh. 30.SE - Prob. 33APCh. 30.SE - Bicyclohexadiene, also known as Dewar benzene, is...Ch. 30.SE - Prob. 35APCh. 30.SE - Prob. 36APCh. 30.SE - The 1H NMR spectrum of bullvalene at 100 C...Ch. 30.SE - Prob. 38APCh. 30.SE - Prob. 39APCh. 30.SE - Prob. 40APCh. 30.SE - In light of your answer to Problem 30-40, explain...
Knowledge Booster
Similar questions
- According to the conventions above, what is the sign ( + or ) of the P.E. change (H) for Rxn 3?arrow_forwardWhich one of the following represents the HOMO of 1,3-butadiene in the ground State?arrow_forward4) How many nodes, other than the node coincident with the molecular plane, are found in the highest energy л MO of 1,3-butadiene?arrow_forward
- Consider the following compounds and answer the following question. 1) 2-Pentanone II) Hexanol III) Dimethylether IV) 2-Butene V) Cyclodecane VI) Acetamide Which compound(s) show π-n* electronic transitions in UV-Vis? Choose... Which compound(s) show n-n* electronic transitions in UV-Vis? Choose...arrow_forwardWhat is the totaly Pi electron binding energy of the ground state for the allyl radical? *CH2-CH=CH2arrow_forwarddichloromethyl vinylsulfideCHCL2-S-CH=CH2 comment very generally on bond length in the molecule. (also point out/ explain unusual or unexpected bond lengths)arrow_forward
- How do the following factors affect absorption frequencies? O-H vs O-D. CH stretch, hybrid orbitals used by carbonarrow_forward7. Consider the C=O stretching data for the following cyclic ketones: cyclopropane 1813 cm³¹; cyclobutanone 1791 cm³¹; cyclopentanone 1740 cm³¹. (a) which ketone has the strongest bond? (b) where in the trend would you expect the C=O stretch of cyclopropenone? (Use the hybridization information in the same way we used hybridization for C-H stretching.)arrow_forward3. Spectroscopy in UV and the visible region. Principles of UV/Vis spectroscopy. The main blocks of the recording double-bean spectrophotometer. Connection of UV-spectra with the structure of organic medicinal compounds. The nature and methods of imaging electronic spectra. Classification of electronic transitions by type of molecular orbitals. Diagram of changes in energy levels during the conjugation. Position and intensity of absorption bands of isolated and conjugated chromophores. Spatial obstacles to conjugation and their spectral reflections.arrow_forward
- What IR frequencies would enable a chemist to distinguish between these molecules? CH;CH2OH and CH;CH2OCH;CH3 and CH, HCHCHCCIICH CH, d 3000-3100 cm-1 (=C-H)| 1620-1680 cm-1 (C=C) 3200-3400 cm-1 (OH) || 3000-3100 cm-1 (=C-H)arrow_forwardThe infrared absorbtion of the N-H stretch in amines occurs approximately at a wavelength of 2.9 x 10-6 m. What is the approximate vibrational force constant, k, of N-H bond? Note: you can assume the reduced mass is equal to the mass of the H atom (which is reasonable since it's attached to a much heavier atom). 48.0 kg/s? 1.20 x 102 kg/s2 7.0 x 102 kg/s2 4.2 x 10-1 kg/s? 1.3 x 103 kg/s?arrow_forward13C NMR spectroscopy provides valuable information about the environments of a molecule's carbon atoms. Since carbon atoms are often connected to hydrogen atoms, which could split the carbon signal through spin-spin coupling, the coupling between C and H is often "turned off" through the use of broadband decoupling, causing each C signal to appear as a singlet. Draw an isomer of C5H11Cl that would be expected to have four resonances in its 13C NMR spectra.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Organic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage LearningOrganic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning
Organic Chemistry: A Guided Inquiry
Chemistry
ISBN:9780618974122
Author:Andrei Straumanis
Publisher:Cengage Learning
Organic Chemistry
Chemistry
ISBN:9781305580350
Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
Publisher:Cengage Learning