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Cyanides alkynes: acidic hydrogen

Hydrocyanation is the formal addition of hydrogen cyanide to alkenes. alkynes, and dienes to yield nitriles. These reactions can be catalyzed by various copper, cobalt, nickel and palladium catalysts modified with phosphanes and phosphites and/or Lewis acids. Hydrocyanation of carbonyl groups in aldehydes and ketones is covered in Section D.l.3.7. [Pg.389]

CHLORCYAN (506-77-4) CNCl C-N-CL Noncombustible gas. Violent polymerization can be caused by chlorine or moisture. Violent reaction with alcohols, alkenes, and alkynes (violent exothermic reaction) acids, acid salts, amines, strong alkalis, olefins, strong oxidizers. Contact with acid forms toxic hydrogen cyanide gas. Mixtures with benzene or cyanogen halides yield hydrogen chloride. In cmde form, this chemical trimerizes violently if catalyzed by traces of hydrogen chloride or ammonium chloride, forming cyanuric chloride. Alkaline conditions will convert this chemical to... [Pg.227]

The synthetic utility of oxazoles as azadienes was further advanced when Grigg and co-workers reported that the Diels-Alder reactions of oxazoles with alkynes provided furans via a tandem Diels-Alder retro-Diels-Alder sequence. Thus 5-ethoxy-4-substituted oxazoles 119 reacted with dimethyl acetylenedicar-boxylate in cold ether to yield 2-ethoxy-3,4-furandicarboxylic acid dimethyl ester 121 in >50% yield (Fig. 3.33). In this case, the intermediate cycloaddition adduct 120 extrudes a molecule of hydrogen cyanide or a nitrile derived from the C-4 substituent of the oxazole, via a retro-Diels-Alder reaction to provide a substituted... [Pg.436]


See other pages where Cyanides alkynes: acidic hydrogen is mentioned: [Pg.641]    [Pg.721]    [Pg.722]    [Pg.758]    [Pg.334]    [Pg.385]    [Pg.481]    [Pg.389]    [Pg.231]    [Pg.240]    [Pg.289]    [Pg.7]    [Pg.151]    [Pg.16]    [Pg.27]    [Pg.351]    [Pg.141]    [Pg.266]   
See also in sourсe #XX -- [ Pg.2 , Pg.3 , Pg.4 , Pg.5 , Pg.7 ]

See also in sourсe #XX -- [ Pg.2 , Pg.3 , Pg.4 , Pg.5 , Pg.7 , Pg.11 ]




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Acid cyanides

Alkynes acidic hydrogen

Alkynes acidity

Alkynes hydrogenation

Cyanides hydrogen cyanide

Hydrogen cyanid

Hydrogen cyanide

Hydrogen cyanide acidity

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