C/ CI CI pair B The disubstituted cyclohexanes in pair B are: enantiomers. diastereomers. ○ identical. Consider the disubstituted cyclohexane structures in pair A. Cl CI CI pair A C/ The disubstituted cyclohexanes in pair A are: identical. diastereomers. enantiomers.

(8) Consider the compound trans-1,3-di-tert-butylcyclohexane. a. Draw the two chair conformers expected for the compound. b. What is the most stable conformer of the compound? Draw it if it is not already drawn.

Q2: Drawn are four isomeric dimethylcyclopropanes. a. How are the compounds in each pair related (enantiomers, diastereomers, constitutional isomers): A and 8; A and C; B and C, Cand D? b. Label each compound as chiral or achiral. c. Which compounds, alone, would be optically active? d. Which compounds have a plane of symmetry? e. Which of the compounds are meso compounds? f. Would an equal mixture of compounds C and D be optically active? What about an equal mixture of B and C?

Drawn are four isomeric dimethylcyclopropanes. a.How are the compounds in each pair related (enantiomers, diastereomers, constitutional isomers): A and B; A and C; B and C; C and D? b.Label each compound as chiral or achiral. c.Which compounds alone would be optically active? d.Which compounds have a plane of symmetry? e.How do the boiling points of the compounds in each pair compare: A and B; B and C; C and D? f.Which of the compounds are meso compounds? g.Would an equal mixture of compounds C and D be optically active? What about an equal mixture of B and C?

Classify each attached pair of compounds as stereoisomers or conformations: (a) X and Y; (b) X and Z.

When two six-membered rings share a C—C bond, this bicyclic system is called a decalin. There are two possible arrangements: trans-decalin having two hydrogen atoms at the ring fusion on opposite sides of the rings, and cis-decalin having the two hydrogens at the ring fusion on thesame side.a.Draw trans- and cis-decalin using the chair form for the cyclohexane rings. b.The trans isomer is more stable. Explain why.

a. What hydrocarbon with molecular formula C4H10 forms only two monochlorinated products? Both products are achiral. b. What hydrocarbon with the same molecular formula as in part a forms three monochlorinated products? One is achiral and two are chiral.

Drawn are four isomeric dimethylcyclopropane. a. How are the compounds in each pair related (enantiomers, diastereomers,constitutional isomers): A and B; A and C; B and C; C and D?b. Label each compound as chiral or achiral.c. Which compounds, alone, would be optically active?d. Which compounds have a plane of symmetry?e. Which of the compounds are meso compounds?f. Would an equal mixture of compounds C and D be optically active? Whatabout an equal mixture of B and C?g. How many stereogenic centers are there for each compound?

Question 32 Label the following pairs as identical or enantiomers or geometric isomers or constitutional isomers: a. 1,1-dibromocyclobutane and 1,2-dibromocyclobutane b. CI- and Ci or:om CH3 CH3 & C. a.: constitutional isomers; b: identical; c: enantiomers a: geometric isomers; b: enantiomers; c: identical a: geometric isomers; b: diastereomers; c: geometric isomers a: diastereomers; b: enantiomers; c: diasteroemers

Compound 1 Br Bri НІ T ... H The correct IUPAC names are: Compound 2 H Br Br I.. H Br The compounds are diastereomers not isomeric enantiomers identical constitutional isomers Compound 1: (2R, 3R)-1,2,3-tribromobutane, Compound 2: (2S, 3R)-1,2,3-tribromobutane Compound 1: (2R, 3S)-1,2,3-tribromobutane, O Compound 1: (2R,3R)-1,2,3-tribromobutane, Compound 2: (2S,3S)-1,2,3-tribromobutane Compound 2: (2R, 3R)-1,2,3-tribromobutane O Compound 1: (2S,3S)-1,2,3-tribromobutane, Compound 2: (2R,3S)-1,2,3-tribromobutane