19) As was discussed in class, a toluenesul fonate is an excellent leaving group. In reaction A shown below, the product shows the addition of an acetate with inversion at the stereocenter where the tosylate (-OTS) was previously attached. The use of radiolabeled oxygens in the acetic acid shows incorporation of the radiolabels at the inverted stereocenter When reaction B was carried out, the product shows the addition of an acetate, although with retention of configuration at the stereocenter where the tosylate (-OTs) was previously attached. Furthermore, the radiolabeled acetic acid shows the production of two regioisomers of the product in a 50:50 ratio. OTs A ACOH ..... „OTs B ACOH Explain (1) why only one isomer is produced in reaction A and (2) why the stereochemistry of that isomer is trans. Explain (3) why trans-isomers are also produced in reaction B and (4) also explain how the radiolabeled oxygens end up scrambled between the two possible regioisomers. You may use pictures to answer these four questions but you may not exceed 35 words total for all of your answers. (think, draw, then write).

19) As was discussed in class, a toluenesul fonate is an excellent leaving group. In reaction A shown below, the product shows the addition of an acetate with inversion at the stereocenter where the tosylate (-OTS) was previously attached. The use of radiolabeled oxygens in the acetic acid shows incorporation of the radiolabels at the inverted stereocenter When reaction B was carried out, the product shows the addition of an acetate, although with retention of configuration at the stereocenter where the tosylate (-OTs) was previously attached. Furthermore, the radiolabeled acetic acid shows the production of two regioisomers of the product in a 50:50 ratio. OTs A ACOH ..... „OTs B ACOH Explain (1) why only one isomer is produced in reaction A and (2) why the stereochemistry of that isomer is trans. Explain (3) why trans-isomers are also produced in reaction B and (4) also explain how the radiolabeled oxygens end up scrambled between the two possible regioisomers. You may use pictures to answer these four questions but you may not exceed 35 words total for all of your answers. (think, draw, then write).

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter24: Catalytic Carbon-carbon Bond Formation

Section: Chapter Questions

Problem 24.36P

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