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Ketones, reaction with aluminum borohydride

Given the structure or name of an aldehyde or ketone, write an equation for its reaction with the following nucleophiles alcohol, cyanide ion, Grignard reagent or acetylide, hydroxylamine, hydrazine, phenylhydrazine, 2,4-dinitrophenylhydrazine, primary amine, lithium aluminum hydride, and sodium borohydride. [Pg.161]

The expected reactions of the cyano group attached to triazine ring carbon with amine, alcohol, and azide nucleophiles have been described <90NKK396>. Reduction of ketone to alcohol with sodium borohydride <88HCA712> and trichloromethyl groups to methyls with lithium aluminum hydride are also reported <86MI 6l2-02>. [Pg.601]

With less hindered hydride donors, particularly sodium borohydride and lithium aluminum hydride, cyclohexanones give predominantly the equatorial alcohol. There has been less agreement about the factors that lead to this result. The equatorial alcohols are, of course, the more stable of the two isomers. The stereochemistry of hydride reduction is determined by kinetic control, but it was argued that the relative stability of the equatorial alcohol might be reflected in the transition state and be the dominant factor when no major steric problems intervened. The term product development control was introduced to indicate this explanation of the reaction stereochemistry. A number of objections were raised to this idea, primarily on the basis of the Hammond principle. The common hydride reductions are exothermic reactions with low activation energies. The transition state should resemble starting ketone and reflect little of the structural features that are present in the product, so that it is difficult to see why product stability should determine the product composition. [Pg.135]

In the general context of donor/acceptor formulation, the carbonyl derivatives (especially ketones) are utilized as electron acceptors in a wide variety of reactions such as additions with Grignard reagents, alkyl metals, enolates (aldol condensation), hydroxide (Cannizzaro reaction), alkoxides (Meerwein-Pondorff-Verley reduction), thiolates, phenolates, etc. reduction to alcohols with lithium aluminum hydride, sodium borohydride, trialkyltin hydrides, etc. and cyloadditions with electron-rich olefins (Paterno-Buchi reaction), acetylenes, and dienes.46... [Pg.212]

If other reactive moieties are present a cyclopropanecarbonyl compound can be converted to the corresponding cyclopropylalkane using various conditions. Thus, 3,4-benzotricy-clo[4.3.1.0 ]dec-3-en-2-one yielded 3,4-benzotricyclo[4.3.1.0 ]dec-3-ene in excellent yield on treatment with sodium in liquid ammonia. di-l-Methylcyclopropane-l,2-dicarboxylic anhydride underwent a similar reaction to afford isomeric lactones on treatment with lithium aluminum hydride or sodium borohydride in tetrahydrofuran. On the other hand, ionic hydrogenation (triethylsilane in trifluoroacetic acid and water) of cyclopropyl phenyl ketone gave a complex reaction mixture and very little benzylcyclopropane. ... [Pg.1767]

Aldehydes and ketones can be reduced using sodium borohydride or lithium aluminum hydride. The reaction is base-initiated with hydride ion as the nucleophile. One mole of sodium borohydride or lithium aluminum hydride reduces four moles of aldehyde or ketone the reaction mixture is then acidified to produce the neutral alcohol. [Pg.258]


See other pages where Ketones, reaction with aluminum borohydride is mentioned: [Pg.438]    [Pg.293]    [Pg.62]    [Pg.347]    [Pg.911]    [Pg.315]    [Pg.150]    [Pg.147]    [Pg.438]    [Pg.2]    [Pg.476]    [Pg.2013]    [Pg.210]    [Pg.293]    [Pg.86]    [Pg.952]    [Pg.953]    [Pg.438]    [Pg.325]    [Pg.1239]    [Pg.625]    [Pg.87]    [Pg.470]    [Pg.271]    [Pg.79]    [Pg.170]    [Pg.1197]    [Pg.18]    [Pg.170]    [Pg.414]    [Pg.170]    [Pg.79]    [Pg.131]    [Pg.25]    [Pg.79]    [Pg.111]    [Pg.236]    [Pg.1792]    [Pg.170]    [Pg.268]    [Pg.336]    [Pg.401]    [Pg.336]   
See also in sourсe #XX -- [ Pg.329 ]




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Reaction with ketone

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