Question

19-26 thanks!

PART 3: 2,3-BUTANEDIOL CH-CH(OH)-CH(OH)-CH, mirror images, not superimposable Build as many models of 2,3-butanediol as you can. First, attach two carbons with a single bond. To each carbon add one carbon, one hydrogen, and one oxygen. To complete the structure, Ti the remaining hydrogen atoms. Remember, a model is not different if it is completely superimposable on one already constructed! 13. How many stereochemically different models are possible for 2,3-butanediol? 14. What characteristic does one of these models have that makes it different? 15. What stereochemical name is given to structures that contain chiral carbons but also contain a plane of symmetry? Draw its Fischer Projection formula. 16. How are the remaining (different structures related to each other: enantiomers, diastereomers, or identical? 17. Draw the Fischer Projection Formulas for each model in #16 (again orient the carbon chain up and down). Are the mirror images "superimposable?" 18. Interchange any two of the groups located at one of the chiral centers on one of the models in #16. What is the stereochemical relationship of the resulting structure with the one that used to be its mirror image? Will this 'new' model be "optically active?" Why or why not? PART 4: 2,3-DICHLOROPENTANE CH-CH(CI)-CH(CI)-CH,CH, Build a model of 2,3-dichloropentane. Start with two carbons, attached via a single bond. Add a hydrogen, a chlorine, and a carbon atom to the first carbon and add a hydrogen, a chlorine and an ethyl group (-CH-CH) to the other carbon. Your partner should build another model which has a different configuration (R & S) at each chiral (stereogenic) carbon. 19. How are the two models of 2,3-dichloropentane related: enantiomers, diastereomers, or identical? 20. How many chiral carbon atoms does 2,3-dichloropentane contain? How many "optical isomers" are theoretically possible? 21. Draw the Fischer Projection Formula for each model constructed and assign the R and S configurations. (Again orient the carbon chain up and down and remember, since there are

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Answer 1

Part - y 2,3 -Dichloropentane 14) y denotes Chiral Carbon Model 1 Model 2 (1 E 10 A spiny hridised Courbon, which four atoms or groups of atoms should be ef uie entirely different , [xy J2 plane t i CH ÇAS LE Enantiomora) Music Non-1 DÉMhe. Mirror Image, but Sefuerimposable I Symmetry By taking minor Image of Model I Configuration (R/3) about each Chiral Carbon will be different .. Enantiomers The two Models of 2,3-dichloropentane will be adith I have no symmetry whatsoever. as they are enteri Be splatsiotery osoba tond (20) Since In 2,3 - Dichloropent ane, there are - centre/ Carben, This No. of optical isomers 2 Chiral possible = 2 = 2* 2 noot Chirad T =4. Centre H , Do Numbering in decreasing order of Atomic Number 12 ] clockwire (R) 1327] Antichockarral e (Provided least priority group must go away from &H (25,38) Viewer ( fisher's assumption - Vertical lines are gring into the plane White Horizontal lines are coming out of the Plane) -

Morror Image a son a los & R, 33 Het LLLLL enantiomenic mistere / Racemuz Minhena Equimolar minhure will result i n no optical actin's to enternal compensation to Racenie Minture are oftically inactive (equinolas misture) Switch about 1 Choral 23.6 Carbon) 24. RH نااااالللللللل TH و ا ا Car, 3R) enantiomers Chr .) Non Mirror image a diperimposable (25, 35)

structures past (24) chuchure H 1. I-m , I TV 2-1 ao 0 Diastereomens 1 ( Same Structure with not related by mirror Images) 026) structural formula of the compounds is same but the compounds are not related by a mirror image Duey mayo Though, all would be optically active as all compounds are Choral (asymmetric in nature), 13203 clockwire (R) provided 2 the leart gemonity group't i 027) . Esch gering away from the viewer. (R)- 2 - hydrony butinad (R- enantiomer) TOH H)191111

sov jetçcho ho CO CPO 발 R-Z -hadrozybetimal or the use After Photobromination, 2 Chiral Carbous are present . so no. of Stereochemically differents isomers = 2h no. of Chical - Carben 722Y. CHO 태이 optically active # 94 Here for E BB 32H 3CM3 (GR, 35) 129,38) a Nem- superimpotable Mirror Image - Enantiomen Switch about this - Chiral Carben W C CHO na co Ho (5) on BmSL-M ele) _ Br. ! Image 023) E-H palon -Superimposable morror 9 ( Enantiomem) on Narthing - iron Chen still has & Configuration stell optically active. ہے۔