Question

age 7 19. The reaction of CH, CH, CCH, CH, with H,/Ni forms a. pentane. b. one particular chiral pentanol. c. an equimolecular mixture of two chiral pentanols . d. one achiral pentanol. e. no product. 20. The p-orbital of a methyl radical carbon, CH,, Contains how many electrons? a. 1 b. 2 e. 3 d. 4 e. 0 21. (2R, 35)-2,3-Dichlorobutane and (25, 3R) -2,3-dichlorobutane are: a. enantiomers b. diastereomers e. identical d. conformational isomers e. constitutional isomers 22. Which reaction must take place with retention of configuration at the stereocente r? OB a. Ci CH, CCH, Br + HC1 CH, CCH, Br сHF св, снсн, он + РC1, b. — сн, снсн, C1 CH, P CH2 F O 10 CH, CHCH, OH (CH,C)20 CH, CHCH, 0CH, + CH, COHI CH, F d. More than one of these e. None of these 23. Which is a meso compound? a. (2R, 3R)-2,3-Dibromobutane b. (2R, 3S)-2, 3-Dibromopentane c. (2R, 4R)-2, 4-Dibromopentane d. (2R, 4S)-2, 4-Dibromopentane e. None of these

Answer 1

| OH 3. , -CH, Lă– cu, “CH, P./oi , HC-CH, -CN KH-CH, Achiral . Ans: @ - 20 CH₂ I- - Ans: @ CH3 He for $#me Her с 2 CH3 Same Ans: (22, 3s) (25, 30) 애 V thel H.C - ċ-CHy Br G-CH₂ Br CH,F CH₂F () racimic CH3 -CH-CH, 01+ . tpa, - CH₂F HC - CH SNZ -> A -CH-CH-C). no Chanx - CH₂ F in stereo Obrasch with Chemistry takes place relentim. Ang @ : ii bic c) Jaz SH3 # Ans (20.45)-2,4-dibromo pentane. C43