五-旋光异构习题及答案

第五章旋光异构4下列化合物中哪个有旋光异构体？如有手性碳，用星号标出。指出可能有的旋光异构体的数目。a.CH3CH2CHCH3Clb.CH3CH=C=CHCH3c.CH3d.e.OHOHf.CH3CHCHOHCOOHCH3g.HOOHh.OCH3i.j.CH3答案：a.CH3CH2CHCH3Cl(2个)b.**CH3CH=C=CHCH3(2个)c.CH3*(2个)d.e.OHOH(无)(无)f.CH3CHCHOHCOOHCH3***(22=4个)g.HOOH(无)h.OCH3(2个)i.(2个)j.CH3(无)**5下列化合物中，哪个有旋光异构？标出手性碳，写出可能有的旋光异构体的投影式，用R，S标记法命名，并注明内消旋体或外消旋体。a.2－溴代－1－丁醇b.α,β－二溴代丁二酸c.α,β－二溴代丁酸d.2－甲基－2－丁烯酸答案：a.CH2CH2CH2CH3OHBrCH2OHHBrCOOHHBrCOOHHBrCH2CH3(R)(2R,3R)CH2OHBrHCH2CH3(S)b.HOOCCHCHBrCOOHBr(meso-)COOHHBrCOOHBrHCOOHBrHCOOHHBr(2S,3S)c.H3CCHBrCHCOOHBrCOOHHBrCH3HBrCOOHBrHCOOHBrHCOOHHBrCOOHBrH(2S,3R)(2R,3S)(2S,3S)(2R,3R)COOHBrHCH3HBrd.CH3C=CHCOOHCH3(无)7分子式是C5H10O2的酸，有旋光性，写出它的一对对映体的投影式，并用R,S标记法命名。答案：COOHHCH3CH2CH3(R)COOHH3CHCH2CH3(S)C5H10O28分子式为C6H12的开链烃A，有旋光性。经催化氢化生成无旋光性的B，分子式为C6H14。写出A，B的结构式。答案：Π=1C6H12ACH2=CHCHCH2CH3*CH3BCH3CH2CHCH2CH3CH39（+）－麻黄碱的构型如下：CH3HNHCH3C6H5HHO它可以用下列哪个投影式表示？C6H5HOHCH3HNHCH3CH3HNHCH3C6H5HOHC6H5HOHHCH3NHCH3C6H5HOHHH3CNHCH3a.b.c.d.答案：b10指出下列各对化合物间的相互关系（属于哪种异构体，或是相同分子）。a.b.c.d.COOHCH3CHCH2CH3HCH3CCOOHCH2CH3COOHHCH3C2H5COOHH3CC2H5HOHCH3HOHHCOOHCOOHHHOCH3HOHHHOOCOHCH3OHHCOOHHOHHCH3HOe.CH3HOHCH3CH3HHCH2OHf.HCOOHCOOHHHHCOOHHOOCg.HHCOOHHHCOOHHOOCHOOCh.CH2OHHOHCH2OHCH2OHHOHCH2OH答案：a.相同(对映体)b.相同c.非对映异构体d.非对映异构体e.构造异构体（官能团位置异构）f.相同g.顺反异构h.相同11如果将如（I）的乳酸的一个投影式离开纸面转过来，或在纸面上旋转900，按照书写投影式规定的原则，它们应代表什么样的分子模型？与（I）是什么关系？COOHHOHCH3(I)答案：(I)COOHHOHCH3(R)纸面上旋转90oOHHOOCCH3H(S)离开纸面旋转COOHHOHCH3(S)(对映异构)(对映异构)