Page 980 - Advanced Organic Chemistry Part A - Structure and Mechanisms, 5th ed (2007) - Carey _ Sundberg
P. 980

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     964                    charges from MP4SDQ/6-31G + ZPE computations. Analyze the computational
                            output in order to answer the following questions:
     CHAPTER 10
     Concerted Pericyclic
     Reactions
                                    +   CH 2  C  O              O   or           or
                                                                         O                O
                                                          1, [2 + 4]    2, [2 + 2]    3, [2 +2]



                           a. In very broad terms, why is the [2 + 2] product 2 favored over the other
                              possible products? Draw a reaction potential energy diagram to illustrate your
                              conclusion.
                           b. More specifically, why is product 2 preferred to product 3? What structural
                              features account for this preference?
                           c. What structural features of TS 1 make it less favorable than TS 2?
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