Problem Set #4, 5.12 Spring 2003 Due Monday, March 10, 4pm 4pts. 1. a) Label each pair as enantiomers, diastereomers, or same molecule. b) Label each stereocenter with its R or S configuration. Pair 1: F Br \ / C / \ H D and F D \ / C / \ H Br Enantiomers Pair 2: HO CH3 \ / C / \ Br OH and HO Br \ / C / \ OH CH3 Enantiomers Pair 3: Cl Cl \ / C / \ H H and Cl Cl \ / C / \ H H Same molecule (ring flip) Pair 4: Ph H OH \ / \ C / \ / H3C R CH3 and H H OH \ / \ C / \ / H3C Ph CH3 Diastereomers (front = S, back = S) 2. a) Label each molecule as chiral or achiral. b) Label each stereocenter with its R or S configuration. c) Label all of the meso compounds. Molecule 1: H | H---C---H | H Chiral Molecule 2: N / \ H H Achiral Molecule 3: Me | Me--C--Me | S Achiral (Meso) Molecule 4: Et | C=O | Me Achiral Molecule 5: Br | Br--C--Br | Br Chiral Molecule 6: CH3 | H---C---CH3 | CH3 3. a) There are three different constitutional isomers of dichlorocyclopentane. Draw them. Cl Cl \ / C / \ Cl Cl Cl | C-C-Cl | | C C Cl | C-C-Cl | | C C b) There are seven different stereoisomers of dichlorocyclopentane. Draw all of them. c) Label each stereocenter as R or S. d) Label each structure as chiral or achiral. e) Label any meso compounds. Cl Cl \ / C / \ Cl Cl achiral (meso) Cl Cl \ / C / \ Cl Cl achiral (meso) Cl Cl \ / C / \ Cl Cl chiral Cl Cl \ / C / \ Cl Cl chiral Cl Cl \ / C / \ Cl Cl chiral Cl Cl \ / C / \ Cl Cl chiral Cl Cl \ / C / \ Cl Cl chiral