Hull Exam 3 Review Flashcards
Out, in, endo, exo: which have the same stereochem (both wedge or both dash)?
Out & endo, in & exo
Diels-Alder retrosynthesis: when you see an EWG what does it have to be?
Endo
Reactant: phenol
Reagent: H2CrO4
Product:
p-benzoquinone (know what it looks like)
Reactant: phenol
Reagents: K2CrO4, H2SO4
Product:
p-benzoquinone (know what it looks like)
Reactant: hydroquinone (know what it looks like)
Reagents: K2CrO4, H2SO4
Product:
p-benzoquinone (know what it looks like)
Reactant: 2-hydroxyphenol
Reagents: K2CrO4, H2SO4
Product:
ortho-quinone (know what it looks like)
Reactant: 1°, 2°, or 3° (not 4°) benzylic C
Reagents: H2CrO4, 🔺
Product:
Benzylic C replaced by COOH
Reactant: benzene
Reagents: Cl2, FeCl3
or Br2, FeBr3
or Br2, AlBr3
Product:
Chlorobenzene + HCl
or bromobenzene + HBr + FeBr3
Reactant: benzene
Reagents: HNO3, H2SO4
Product:
Nitrobenzene (NO2) + H2O
Reactant: benzene
Reagents: SO3, H2SO4
Product:
Benzene with SO3H on it
Reactant: benzene
Reagents: RCl, AlCl3
Product:
Benzene-R + HCl
When does Friedel-Crafts Alkylation and Acylation fail?
When meta directors are on the benzene ring
Strongly activating o,p-directors
-NH2, -NHR, -NR2, -OH, -OR
Moderately activating o,p-directors
-NH-ketone
-NH-carbonyl-Ar
-O-ketone
-O-carbonyl-Ar
Weakly activating o,p-directors
-R, -phenyl
Weakly deactivating o,p-directors
-F, -Cl, -Br, -I
Moderately deactivating m-directors
-aldehyde
-ketone
-COOH
-COOR
-CONH2
-SO3H
-CN
Strongly deactivating m-directors
-NO2, -NH3+, -CF3, -CCl3
Reactant: nitrobenzene
Reagents: Fe/HCl
Product:
NH2 replaces NO2
Reactant: nitrobenzene with ketone at meta position
Reagents: Pd-C, H2
Product:
Simultaneously reduces NO2 to NH2 and chops off double bond O
Reactant: chlorobenzene
Reagents: NaNH2, NH3(l)
Product(s):
LG leaves, benzene w/ NH2 where LG was or adjacent to where it was (through benzyne intermediate)
Reactant: chlorobenzene
Reagents: NaOH, H2O, 300 psi
Product(s):
LG leaves, benzene w/ OH where LG was or adjacent to where it was (through benzyne intermediate)
Reactant: chlorobenzene
Reagents: Na2CO3, H2O, 🔺, 300 psi
Product(s):
LG leaves, benzene w/ OH where LG was or adjacent to where it was (through benzyne intermediate)
Reactant: chlorobenzene
Reagents: NaOH, H2O, 300 °C then HCl work-up
Product(s):
LG leaves, benzene w/ OH where LG was or adjacent to where it was (through benzyne intermediate)
Reactant: 2,4-dinitrochlorobenzene
Reagents: NH2NH2
Product:
HN-NH2 replaces Cl
Reactant: 2,4-dinitrochlorobenzene
Reagents: NaOMe
Product:
-OMe replaces Cl
Reactant: 4-nitrobromobenzene
Reagents: CN
Product:
CN replaces Br
Reactant: 1,3-dinitrobenzene saturated with chlorines
Reagent: NaN3 (excess)
Product:
N3 replaces chlorines that are o,p- to the NO2s or ortho to both
Reactant: 2,4-dinitrochlorobenzene
Reagents: 1. Na2CO3, H2O, 100 °C
2. HCl, H2O
Product:
OH replaces Cl
Reactant: 2,4-dinitrochlorobenzene
Reagents: NaCN
Product:
CN replaces Cl
Rank the groups from most EDG to most EWG
EDG
-NR2
-OMe
-tBu, -Me
-H
-Br, -Cl
-COOEt
-CF3
-NO2
EWG
Reactant: nitrobenzene
Reagents: H2/Pd
Product:
NH2-benzene
Reactant: NH2-benzene
Reagent: HNO2
Product:
N2+ -benzene
Reactant: N2+ -benzene
Reagent: H2O
Product:
Phenol
Reactant: phenol
Reagent: ClCOR (acid chloride)
Product:
Benzene-O-COR
Reactant: benzene-N2+
Reagents: HBr, CuBr
Product:
Bromobenzene
