Assignment 1 For each of the following, draw reasonable resonance structures, including at least the two most stable

Assignment 1

0. For each of the following, draw reasonable resonance structures, including at least the two most stable. Indicate the relative stability of those you have drawn. Indicate the hybridization of any nonhydrogen atom. Draw the resonance hybrid structure!

1. Using Newman projections, draw a torsional energy diagram (like we have in the slide show) for rotations around the red bond. Draw a new structure for every 60 degree rotation.

2) In the following cyclopentanes, build a model and show the most unstable (highest energy, highest steric interaction) conformation, and the lowest (there may be many ties here, so just draw one).

3) Draw the two chair conformations for the following molecules. Indicate which is preferred.

a)                                            b)                                                            c)                                            d) 

4. Discuss briefly with drawings why 6 membered rings are preferred to 5 and 7, and why 4 and 3 membered rings are so strained.
5. Using orbital Linear Combination of Atomic Orbital diagrams (just for the relevant atoms), explain using hyperconjugation, resonance, and induction, how the following alkenes are polarized (where the electron density is, where the partial + and – belong).

6. Draw the mechanism, using curly arrows to predict the product of the reaction of the above alkenes with HBr.

7. Draw a reaction co-ordinate diagram for the above reactions. Also draw the reaction curve the reaction would take to react the “wrong” way.

8. Predict the product of the above reactions with HCl (catalytic) in water.
9. Show the mechanism and predict the product of the following reactions: