Chem 634Professor FoxExam 1Fall 20073 hoursYour Name___________________a1. Provide conditions for the following transformations. Mechanistic details are not required. 4 points each)bcOCO2MeOCO2MeCO2MeCO2MeHOONEt21. BuLi2. NaH3.Br4. H+1. LDA, HMPA2. MeI1)MgBr2)OMeOMeNMe2a2. Indicate whether the reactions below would proceed as indicated. Provide a brief but detailed explanation. If the product does not proceed as shown, indicate the structure of the product(s) that would be formed instead of (or in addition to) the product that is drawn (4 points each). bcNO: Baeyer Villiger proceeds with retentionxOAcOOOOAcmCPBAHO1) KH2)PhBrHOPhNO: would give a mixture of C and O alkylationHOAlso formedPhtBu OLiAlH4tBu OHxNO: LAH delivers hydride from axial face togive the equatorial alcoholtBu OHtBuOH15 points OCO2Me2 Mn(OAc)3, HOAcOCO2MeH3. Provide a detailed arrow pushing mechanismOCO2MeHH+OCO2MeHMn–OAcAcOOAcOCO2MeMnAcOOAcOCO2MeOCO2MeOCO2MeOCO2MeHelectron transferto Mn(OAc)3OCO2MeH+HOCO2MeH4. This question has two parts, both of which deal with the reaction below:a. Provide an arrow pushing mechanism for the reaction above. For this part of theproblem, it is not necessary to explain the stereochemical aspects of the reaction. Justpush the arrows and show how the final product is formed. (10 points)MeOHcat. NaHEtMe EtNHCCl3O+C NCl3CMeOHcat. NaHEtMe EtNHCCl3O+C NCl3CMeO–EtNaHC NCl3CMeOEtN–CCl3MeOEtHMeOEtNHCCl3Me EtNHCCl3O4. This question has two parts, both of which deal with the reaction below:b. Provide a detailed model with explains all of the stereochemical aspects(stereocenters and alkene stereochemistry). (10 points)MeOHcat. NaHEtMe EtNHCCl3O+C NCl3CMeOEtNHCCl3NHOCCl3MeEtNHOCCl3MeEtHHMe EtNHCCl3OClaisen via Chair TS16 points OOH5. Provide a multistep synthesis starting from AANtBuI1)2) H3O+OMgBrOHCrO3, H+OFelkin productLiiBu3BHOH1) H2NtBu2) EtMgBr–HOOOHMeOΔno reactionOHOHMeOHO12ΔHOHOHOMeOH3LiAlH46. Compound 1 does not react when heated. However, reduction of the lactone gives 2, which rearranges to 3 upon heating.a) provide an arrow pushing mechanismHHOHOHOMeOHOOMeOHO1ΔOOMeOHOΔHOHOHOMeOHH3b) provide a stereochemical model that explains why 1 does NOT undergo a Cope rearrangment.2c) provide a model that explains the stereospecificity in the formation of 3.HOMeOOHHOMeO OHOHOHMeOHO2single bond rotations's-cis'HOHOHOMeOHH3Compound 2 can rotate single bonds to adopt a 'single bond cis' conformation,which can undergo the Cope rearrangement to produce cis-single bonds.Cope rearrangement of 1 would produce a cyclic molecule with two trans-bonds. The product would be excessively strained. Because of the lactoneconstraint, 1 cannot adopt a conformation that would lead to cis double
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