5. Assume that the types of strain in the rotation about the C1-C2 bond in 1,2-dibromopropane have the following values. •Torsional strain = 20 kJ/mol •Steric strain between two Br substituents gauche = 13 kJ/mol •Steric strain between two Br substituents eclipsed = 16 kJ/mol •Steric strain between Br and CH3 substituents gauche = 8 kJ/mol •Steric strain between Br and CH3 substituents eclipsed = 10 kJ/mol. (a) Perform a conformational analysis about the C1-C2 bond, analogous to the diagram in Figures 4-4 and 4-7 (Karty). Draw a full rotational energy profile (add E values in kJ/mol on y-axis) drawing each eclipsed and staggered conformation as Newmann projections i.e. 60° rotations for complete rotation about the C1-C2 bond. E (kJ/mol) 0° 360 °

5. Assume that the types of strain in the rotation about the C1-C2 bond in 1,2-dibromopropane have the following values. •Torsional strain = 20 kJ/mol •Steric strain between two Br substituents gauche = 13 kJ/mol •Steric strain between two Br substituents eclipsed = 16 kJ/mol •Steric strain between Br and CH3 substituents gauche = 8 kJ/mol •Steric strain between Br and CH3 substituents eclipsed = 10 kJ/mol. (a) Perform a conformational analysis about the C1-C2 bond, analogous to the diagram in Figures 4-4 and 4-7 (Karty). Draw a full rotational energy profile (add E values in kJ/mol on y-axis) drawing each eclipsed and staggered conformation as Newmann projections i.e. 60° rotations for complete rotation about the C1-C2 bond. E (kJ/mol) 0° 360 °

Pushing Electrons

4th Edition

ISBN:9781133951889

Author:Weeks, Daniel P.

Publisher:Weeks, Daniel P.

Chapter3: Mechanisms

Section: Chapter Questions

Problem 125EQ

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