Geometric isomer

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403221 ??????????????????

• ??. ??. ??????? ???????
• ??????????? ??????????????
• ??????????????????????

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??????????????????
Geometric isomer
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Geometric isomers ????????

• ????????????????????? sp2-C ??????????????????
• ???????????????????????? sp2-C
• ???????????????? --gt cis-
• ???????????? --gt trans-

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Geometric isomers ????????
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Geometric isomers ????????

• ????????????????????? sp2-C ??????????????????
• ?????????????????? sp2-C ???????????????
• ????????? priority ?????????????? sp2-C
• ???????????????? --gt Z- (Zusammen)
• ???????????? --gt E- (Entgegen)

E-2-chloro-2-pentene
Z-2-chloro-2-pentene
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E-2-pentene
Z-2-pentene
Z-3-chloro-3-hexene
E-3-chloro-3-hexene
E-1-bromo-1-chloro-2-fluoroethene
Z-1-bromo-1-chloro-2-fluoroethene
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??????????????? ???????????????????????

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• ??????????????????????????????????????????????????
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• ???????????????????????? ?????????????????????????
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???????????????

• 1. Dehydrohalogenation ??????????????? R-X

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• ????????????????? dehydrohalogenation ??? E2
• ??? KOH ??????????? (alcoholic KOH)
  NaOC2H5/C2H5OH, NaOCH3/CH3OH
• NaNH2/ NH3
• ???????????
• ?????????? C2H5OH, CH3OH

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Saytzeff rule ??????????????? dehydrohalogenation
?????????????????????? alkene ???????????????????
??????????????
???????????? alkene R2CCR2 gt R2CCHR gt R2CCH2
gt trans-RCHCHR gt cis-RCHCHR gt RCHCH2 gt H2CCH2
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• 2. Dehalogenation ??? vicinal dihalide

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3. Dehydration ???????????? R-OH
?????????????
??????????????????? dehydration 3o gt 2o gt 1o
R-OH
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• 4. Reduction ??????????

Lindlars catalyst Pd/CaCO3 ?????????? Pd/BaSO4
???? Ni2B (P-2) ?????
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??????????????????

• Addition

1. Hydrogenation
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• 2. Electrophilic addition
• 2.1 addition of HX

Electrophile (E) reagent ????????????????
????????????????? ??????????????????????????????
?????
Markovnikov addition H ???????? electrophile
??????????? C ????? H ???????
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• ?????????????

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• 2.2 addition of H2SO4

2.3 addition of H2O
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• 2.4 addition of X2

????????????? (anti-addition)
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• 2.5 addition of X2 H2O

???????????????? anti-addition Markovnikov
(Br, Cl ???? electrophile)
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?????????????
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• 2.6 addition of alkene (dimerization)

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• 2.7 addition of free radical (HBr peroxide)

????????????? (??????? anti-Markovnikov)
Br. radical ???? electrophile ??????????? C ?????
H ???????
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• 2.8 hydroboration - oxidation

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• 3. Oxidation
• 3.1 hydroxylation

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• 3.2 ozonolysis

??????????????????????????????????? alkene
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• ?????????
• ???????????????????? a-pinene, A, B, C
• ?????????????????????????
• propene ??? propane
• 1-bromopropane ??? propane
• t-butyl alcohol ??? 2-methylpropane
• 2-bromobutane ??? 1-bromobutane