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Nitriles Vilsmeier-Haack reaction

The Vilsmeier-Haack reaction of electron-rich carbocyclic aromatic compounds (Ar—H) with chloromethyleneiminium salt (1) gives aldehyde derivatives (Ar—CHO), generally in good yield. The intermediate iminium salt (cf. salt 5 Scheme 1) can be treated with hydroxylamine to obtain nitrile derivatives (Ar—CN). Benzene and naphthalene are not sufTiciently electron rich to participate in the Vilsmeier-Haack reaction, but polycyclic hydrocarbons, such as anthracene, do react. Benzene and naphthalene derivatives that possess an electron-releasing substituent (—OMe,—SMe,—NMe2, etc.) af-... [Pg.779]

Alkylation of pyrroles proves to be problematic because the usual Lewis acid catalysts initiate polymerization. The Vilsmeier-Haack formylation, however, leads to the formation of pyrrole-2-carbaldehyde in good yield. The Houben-Hoesch acylation (reaction with nitriles in the presence of hydrogen chloride) provides 2-acylpyrroles ... [Pg.89]


See other pages where Nitriles Vilsmeier-Haack reaction is mentioned: [Pg.271]    [Pg.222]    [Pg.646]    [Pg.222]    [Pg.646]    [Pg.222]    [Pg.468]    [Pg.335]    [Pg.24]    [Pg.171]    [Pg.243]    [Pg.285]    [Pg.329]    [Pg.327]   
See also in sourсe #XX -- [ Pg.2 , Pg.789 ]

See also in sourсe #XX -- [ Pg.789 ]

See also in sourсe #XX -- [ Pg.789 ]

See also in sourсe #XX -- [ Pg.2 , Pg.789 ]

See also in sourсe #XX -- [ Pg.789 ]




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Haack Reaction

Nitriles reactions

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Vilsmeier-Haack

Vilsmeier-Haack reaction

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