1Chem 634Professor FoxExam 1October 12, 20043 hoursYour Name___________________2a1. Provide reagents for the following transformations. More than one step may be required. Mechanistic details are not needed. (five parts; 3 pts each)bChem 634 Exam 1 Your Name___________________ OPhOTMSPhOtBuOHtBucOOCO2Me3d1. (continued)eChem 634 Exam 1 Your Name___________________ O NEt2OO NEt2OTMSOOHO2C4a2. Predict if each of the following reactions would proceed as written. If you feel that the reactionwould proceed, simply write “will proceed as written”.If you feel that the reaction would not proceed as written, provide a brief but detailed explanation, and indicate the structure of the product(s) that would be formed instead of (or in addition to) the product that is drawn (3 points each). bChem 634 Exam 1 Your Name___________________ HOΔOtBuOPh2CuLitBuOHthen H+Ph5c2. (continued). dChem 634 Exam 1 Your Name___________________ EtOOMe2CuLithen H+EtMeCO2MeNCO2MeNΔ6Chem 634 Exam 1 Your Name___________________ 3. Identify the type of selectivity for each reaction. Circle the correct answer. 2 pts each. CHOEtMgBrOHEtvsOHEtchemoselectivityregioselectivitydiastereoselectivityenantioselectivity.achemoselectivityregioselectivitydiastereoselectivityenantioselectivity.bchemoselectivityregioselectivitydiastereoselectivityenantioselectivity.cchemoselectivityregioselectivitydiastereoselectivityenantioselectivity.d1) BH32) H2O2OHHOvsPhCHOEt2ZnMeNOHEtOHEtOHvsLiAlH4HOH3COHOHH3COvsHOH3COH74a. Propose a structure for intermediate A. Propose an arrow pushing mechanism for theformation of A and B. For this part of the problem, it is not necessary to explain thestereochemical aspects of the reaction. Just push the arrows and show how the finalproduct is formed. (9 pts)Chem 634 Exam 1 Your Name___________________ PhPhOOMgBr2 equivOPhPhAH3O+B84b. Propose a model that explains the diastereoselectivity of the reaction (6 pts)Chem 634 Exam 1 Your Name___________________ PhPhOOMgBr2 equivOPhPhAH3O+B95 (a) Write a detailed mechanism for the reaction below. (8 pts)Chem 634 Exam 1 Your Name___________________ IOCH3Pd(PPh3)4PhB(OH)2Na2CO3O12H3CPh105 (b) Unlike the reaction of 1 to 2, the reaction of 3 does not give the analogous product 5. Instead, product 4 is obtained. Write a mechanism for the formation of 4, and explain why 5 is not obtained. (7 pts)Chem 634 Exam 1 Your Name___________________ IOCH3Pd(PPh3)4PhB(OH)2Na2CO3O12H3CPh IOHPd(PPh3)4PhB(OH)2Na2CO3Onot formed35HPhC9H8O411Chem 634 Exam 1 Your Name___________________ 6 a. Propose a structure for intermediate A. Propose an arrow pushing mechanism for theformation of A and B. For this part of the problem, it is not necessary to explain thestereochemical aspects of the reaction. Just push the arrows and show how the final product isformed. (8 points)NClONOAK2CO3BC12H22NOCl12Chem 634 Exam 1 Your Name___________________ 6b. Provide a detailed model that explains the diastereoselectivity of the reaction. Whatconclusion can you make about the stereoselectivity of the enolization event? (7 points)NClONOAK2CO3B13Chem 634 Exam 1 Your Name___________________ 7. Outline a multistep synthesis using any materials with 6 carbons or less (20 points)HHMeMeOH14Chem 634 Exam 1 Your Name___________________ 7.
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