Phản ứng thế nucleophil của Pyridin
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Cơ chế phản ứng thế Nucleophilic của
Pyridine
Reaction occurs by addition of the nucleophile to the
C=N bond, followed by loss of halide ion
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18.7 Fused-Ring Heterocycles
Quinoline, isoquinoline, and indole are fused-ring
heterocycles, containing both a benzene ring and a
heterocyclic aromatic ring
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Quinoline and Isoquinoline
Quinoline and isoquinoline have pyridine-like nitrogen
atoms, and undergo electrophilic substitutions
Reaction is on the benzene ring rather than on the
pyridine ring
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Indole
Has pyrrole-like nitrogen (nonbasic)
Undergoes electrophilic substitution at C3 of the
electron-rich pyrrole
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Purine and Pyrimidine
Pyrimidine contains two pyridine-like nitrogens in a
six-membered aromatic ring
Purine has 4 N’s in a fused-ring structure. Three are
basic like pyridine-like and one is like that in pyrrole
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