MS 4637 - Sacramento City College Chem 420 Unit 8 Alkenes (I)

MS 4637 - Sacramento City College Chem 420 Unit 8 Alkenes (I)

Description: Please do the following Mendelset problems, and problems 1-38 in Ch. 11 of Second Language.
Also do problems 39-42 of Ch 11, writing out a plausible electron pushing mechanism in each case.

Total Problems: 8

  1. Problem # 335

    Carbocations aren't very stable and so don't last very long after they are formed.

    Use curved arrows to show:

    a) how a carbocation reacts with a halide ions to form an alkyl halide.

    b) how a carbocation reacts with water to form an alcohol.

    c) how a carbocation reacts with a base to form an alkene.

  2. Problem # 348

    For the reaction below, draw the structures of the carbocation intermediate and the final product.

  3. Problem # 518

    The alcohol below is protonated and contains an oxygen with a positive charge. Using curved arrows, show the two "legal moves" that result in a neutral oxygen.

  4. Problem # 519

    Let's work through an elimination reaction. Draw the structures for each of the species in the three boxes below (protonated thiol, carbocation, and alkene). Also draw curved arrows to show electron movement. 

  5. Problem # 333

    Let's go over how a carbocation can form from an alcohol.

    Write in the curved arrows to show the formation of the protonated alcohol, and water acting as a leaving group to form a carbocation.

  6. Problem # 319

    For a molecule to undergo an E2 reaction, the leaving group and the beta-proton must be in an anti-coplanar conformation (one atom straight up, the other straight down). Based on this, which compound undergoes E2 reaction with KOtBu faster? Why?


  7. Problem # 341

     Predict the product(s) of the reaction below, and used curved arrows to show a mechanism.

  8. Problem # 531


    E2 elimination reactions require anti-coplanar geometry. (note: some textbooks call this anti-periplanar).
    Let's work through an E2 reaction, and rotate the molecule eblow into an anti-coplanar geometry to predict the product of this E2 reaction.