Organic Chemistry I Exam 2 Makeup 101906

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					                              Organic Chemistry I
                               Exam 2 Makeup
                                   10/19/06
                 Print Name:
                               Last                       first

                 Signature:

Instructions Please initial each of the following on this checklist:

          Check to make sure that you have 10 pages including this one, the two
          blank pages, and a periodic table.
          You may use models. A calculator is not necessary.
          Put your name on this page and the next page.
          Remove the periodic table and cover your paper with it during the exam.
          Answer all parts of the questions. Circle all of your answers.

          Answer all parts of the questions.
          If you have written anything on another page and you would like it to be
          considered as part of your answer, indicate where the rest of the answer is
          located.

          Provide the title of your Organic chemistry book. If you do this and initial
          all of the lines, you will receive one point.




                                                                                  1
                                    CHEM 321
                                Organic Chemistry I
                                     Exam 2
                                     10/20/06
Name:
Part I. Short Answer – (49 total number points) Answer all parts for the following
questions

1) (7 points) Answer the following parts pertaining to the compound depicted below:




                                          O

   a) Put a star on the atoms, which are sp2-hybridized.
   b) Put a circle around the atoms, which are sp-hybridized.
   c) For the remaining carbon atoms, what is their hybridization?


2) (3 points total) Which of the following molecules can exist as cis/trans (E/Z) isomers?
Circle the compound, which do. If there is a stereogenic carbon, put a star on it.

        (a) (CH3) 2C=CHCH2CH2CH(CH3)CH2CH2OH


        (b) (CH3)2C=CHCH2CH2C(CH3)=CHCH2OH


3) (3 points each/total 9 points) Name the following compounds:




                   OH




                                                                                         2
4) (1 point each/total 4 points) Circle the group, which is most acidic in the following
compounds:

                                 O-H                                 O-H

                                                H-O                        Cl
                      O-H                                   Cl


                                S-H                                  O-H

                                               H-O
                     O-H                                   Cl    F


5) (1 point each/ total 3 points) What are the conjugate acids for the compounds below?
Show all lone pair electrons and put charges on the correct atoms.

       a) H2O                                b) NH3                             c) CH3OH


6) (1 point each/ total 3 points) What are the conjugate bases for the compounds below?
Show all lone pair electrons and put charges on the correct atoms.

       a) H2O                                b) NH3                             c) CH3OH




7) (1 point each/19 total points) For each statement, circle the appropriate words to
make the statement correct. More than one word may be correct.

a) Hexahelicene is (achiral, chiral or meso) compound.



b) 2,3-Pentadiene is (achiral, chiral or meso) compound.



c) 1,2-Propadiene is (achiral, chiral or meso) compound.


d) One conformational stereoisomer of (R,R) trans-dichlorocyclohexane converts to (R,R;
RS; SR; or SS) trans-dichlorocyclohexane via a chair flip.


                                                                                           3
Continued 7) For each statement, circle the appropriate words to make the
statement correct. More than one word may be correct.

e) The torsional strain in planar cyclohexane is (higher, lower, or the same) compared to
planar cyclopentane.


f) The ring strain of cyclopropane is (higher, lower, or the same) as compared to planar
cyclobutane.


g) The heat of formation in the standard states of cyclohexane is (more than, less than or
the same) than that of cyclopentane.


h) The heat of combustion in the standard states of cyclohexane is (more than, less than
or the same) than that of cyclopentane.


i) The planar structure of cis-1,2-dimethylcyclohexane is (achiral, chiral or meso)
compound.


j) The relationship between the chair interconversion of 1,1-dimethylcyclohexane are that
they are (conformational enantiomers, conformational diastereomers, or identical).


k) The relationship between the chair interconversion of cis-1,2-dimethylcyclohexane are
that they are (conformational enantiomers, conformational diastereomers, or identical).


l) The relationship between the chair interconversion of trans-1,2-dimethylcyclohexane
are that they are (conformational enantiomers, conformational diastereomers, or
identical).


m) The relationship between the chair interconversion of cis-1,3-dimethylcyclohexane
are that they are (conformational enantiomers, conformational diastereomers, or
identical).


n) The relationship between the chair interconversion of trans-1,3-dimethylcyclohexane
are that they are (conformational enantiomers, conformational diastereomers, or
identical).




                                                                                        4
Continued 7) For each statement, circle the appropriate words to make the
statement correct. More than one word may be correct.

o) The relationship between the chair interconversion of cis-1,4-dimethylcyclohexane are
that they are (conformational enantiomers, conformational diastereomers, or identical).


p) The relationship between the chair interconversion of trans-1,4-dimethylcyclohexane
are that they are (conformational enantiomers, conformational diastereomers, or
identical).


q) (2 points) Propanol is (aprotic, protic, apolar, and/or polar) solvent.


r) The inversion of Compound A is (higher, lower or the same) compared to the energy of
inversion of Compound B.
              N

                                              N


        Compound A                       Compound B




Part 2 (51 points) Answer all parts for the following reactions.
8) (9 points) Star the chiral (stereogenic centers) in the compound (cortisone) below.
Then, assign chirality (R or S) to each of those centers.
                                             OH
                                     O
                                 CH3
                     O                    OH
                     CH3     H

                         H       H
        O




                                                                                         5
9) (16 points) Given any inorganic materials including D2O but excluding lithium,
provide the synthetic pathway for the conversion depicted below (7 points). For every
step, you must show the mechanism (9 points).
                D
                            from




10) (10 points) Provide the 3-D structure (3 points) of the product and mechanism (5) for
the reaction below. Give the HOMO/LUMO for the reaction (2 points). Star the chiral
centers and identify R/S.
       CH3CDTBr           +        NaCN
            (R)




                                                                                        6
11) (16 points) Draw all of the possible chair forms and stereoisomers for trans-1-
isopropyl-2-methylcyclohexane and trans-1-isopropyl-3-methylcyclohexane. State the
relationships between the isomers, state the relationships between their flipped isomers,
label R/S if applicable (for all chiral centers), and specify their stability.




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