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Organic Chemistry I Test 2 Extra Mechanism Practice Problems Note: In each of these cases, I am asking you to draw the mechanism for the product shown. In some cases where both elimination and substitution may occur, there may be another product in addition to the one shown. And in cases where elimination is happening, there may be an additional structural isomer that could form. Regardless, you should be able to draw the mechanism for how the product that IS shown would have actually formed.

1.

2.

3.

4.

5.

6.

Br

ONa

O

OK

BrH HO

OBr

OH

Heat

HS

Br S

Br

OK

OK

BrH

T

T

T

SN2: No intermediates

SN1: 3 steps1. Cation formation2. Cation Capture3. Loss of proton

Mech explains changes in:1. Bonds2. Lone pairs3. Formal charges

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7.

8.

9.

10.

OH

BrH

Br

OH

Heat

O Br2, hv O

Br

BrBr2, hv

T

T

T

E1:1. Cation formation2. Loss of a neighbor H

Radical Bromination:1. Abstract H using Br radical2. Attach Br to carbon radical

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In these problems, both predict the major product and draw the mechanism for its formation. If you expect both substitution and elimination to occur, draw both (bit if there is more than one alkene isomer possible, just draw the one that would form to greater extent,) and draw the mechanism for both. ASSUME ANYTHING THAT STARTS CHIRAL IS OPTICALLY ACTIVE TO START.

1.

2.

3.

4.

5.

6.

BrSNa

OK

BrH

HO

BrH

NaO

BrH3C

DH

HO

BrH3C

DH

BrHD

ONaOH

T

T

T

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7.

8.

9. 10.

11.

HBr

HD

ONaOH

BrHD

OH2O

Br2, hv

Br2, hv

T

T

T