Chem 634 February 10, 2004Pre-Problem Set Prof. Fox1. Assign all stereochemistry (R or S; E or Z)HCH3CHOCH2BraOHBrOOClClcdbt-But-But-But-But-But-BuOHBrBrOH2. For each pair, which is more stable?abc3. Indicate the relationship for each pair below: enantiomers, diastereomers, or mesoHOCH3HHHOCH3HCH3OHOHHCH3abHOOHHO OHSS S RBrBrBrBrt-But-Bu4) For each pair, indicate which is more stable. Use a clear picture to explain why5. Provide a detailed arrow pushing mechanism for the following reactionBrO OHHHBu3SnHAIBN6. Draw Newman projections for the staggered and eclipsed forms of n-butane. Give therelative energies of all of the eclipsed and staggered conformers.7. Gauche butane is ~ 0.8 kcal/mol higher in energy than anti butane. The A-strain of amethyl group on cyclohexane is ~1.7 kcal/mol. Use Newman projections to explain therelationship in detail.BrONaSMe8) Provide a mechanismSMeO9) The reaction below is an SN2 process. However, the absolute configurations of the starting material and products are both R. Explain. (Hint: this is a trick question).SOSHOBrNaH(R)(R)12) Provide a detailed explanationBrBrXbutNaOtBuNaOtBu10) Which reaction is faster (A or B)? Why?HOHBrBrA BOH BrHBr11) Which reaction is faster (A or B)? Why?EtEtHOHOHBrABHBrBrEtEtBr13 ) Provide a detailed arrow pushing mechanism.HOTscatalytic
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