CHEMISTRY 241AEXAM 3 McGrathApril 4, 2001Name: Key ID#: There is scratch paper at the end of the exam,as well as a periodic table.1. ( 24 )2. ( 12 )3. ( 32 )4. ( 12 )4. ( 20 )B ( 2 )Total (102)GOOD LUCK!Bonus ( 2 pts): If the earth were a solid sphere, how many steps would ittake to walk around the equator (to the nearest order of magnitude)?YOU SHOULD HAVE 6 PAGES!!!1. ( 24 pts) Draw the principle organic product in each of the following reactions. Indicateall stereoisomers formed where appropriate. (McMurray 7.39b, 9.62b, 8.25a,8.26b, 8.24b, cf8.33)(a)(b)(c)(d)(e)(f)NaNH2NH31. OsO42. NaHSO3Br2CH2Cl2H3CCH3Br2(2 equiv.)BrCH3LiNH3HgSO4H2SO4H2OOHOHBrBrBrBrH3CCH3Br BrBr BrCH3CH3O2. ( 12 pts) When 4-penten-1-ol is treated with aqueous Br2, a cyclic bromo ether isformed, rather than the expected bromohydrin. Propose a mechanism, using curvedarrows to show electron movement. (This is not a synthesis problem! The ONLYreagents you can use are those above and below the arrow as shown!) (McMurray7.48)H2C CHCH2CH2CH2OHBr2H2OOCH2BrBrBrBrH CH2CH2CH2OHH HOBrH2CHHBrBr3. ( 32 pts) Provide sequences of reactions to carry out the following transformations fromthe indicated starting materials. You may use any inorganic reagents as well as organiccompounds of three carbons or less. More than one step will be needed. Give thenecessary reagents for each individual step. Give the product of each individual step.(a) (McMurray 8.32)CH3CH2CH2CH2C CH???H HCH3CH2CH2CH2CH3H HCH3CH2CH2CH2C CCH3CH3HCH3CH2CH2CH2H1. NaNH2/NH32. CH3IH2LindlarCH2I2Zn(Cu)(b)CH3CH2CH2C CCH2CH2CH3CH2CH2CH3HCH3CH2CH2H1. NaNH2/NH32. CH3CH2CH2IH2LindlarBr2CH2Cl2CH3CH2CH2C CH???CH3CH2CH2CH2CH2CH3BrBrHH(c) Provide the structures of all stereoisomers of the indicated final products above that areformed as a result of your synthetic sequence.For part (a): For part (b):CH3CH2CH2CH2CH2CH3BrBrHHCH3CH2CH2CH2CH2CH3BrBrHHH HCH3CH2CH2CH2CH3H HH HCH3CH2CH2CH2CH3H H4. ( 12 pts) (a) Penicillin V is an important broad spectrum antibiotic. Unfortunately,pencillin antibiotics are becoming less and less potent as new strains of bacteriabecome resistent. It has the structure shown directly below. Label each stereogeniccenter clearly and unambiguously as either R or S. (6 pts) How many enantiomersof penicillin V are possible? (3 pts) How many diastereomers? (3 pts) (McMurray9.41)NSNCH3HH HCH3HOOCOCOOHR RSPossible enantiomers: __1__ Possible diastereomers: __6__5. ( 20 pts) Determine whether the two structures in each of the following pairs representconstitutional isomers, stereoisomers, , or are identical. Indicate your choicenext to each pair. If stereoisomers, are they enantiomers or diastereomers?Diastereomers(a) (b)HO HH OHHO OHH HOH OH(e)(d)(e)BrClHCH3ClCH3HBrOH OHOHOHOHOHEnantiomers