Acetone hydrogen cyanide reaction with

Synthesis of methyl methacrylate is fundamental to the production of the transparent plastic polymethyl methacrylate (PMMA), and is estimated at over two million metric tons per year. The monomer is most commonly synthesized via the well-established Acetone Cyanohydrin (ACN) process, as shown below, based on easily available raw materials such as, acetone, hydrogen cyanide, methanol and sulfuric acid. Reaction of acetone and hydrogen cyanide yields acetone cyanohydrin as an intermediate, which is then reacted with excess amount of concentrated sulfuric acid, followed by thermal cracking to form methacrylamide sulfate. The methacrylamide sulfate intermediate is then further hydrolyzed and esterified with aqueous methanol to form methyl methacrylate. 

Methacrylic acid can also be produced by a variety of processes including oxidation of ethylene, propylene, and isobutylene. The most common commercial process for making methacrylic acid is the acetone cyanohydrin (ACN) process. The feedstocks for this process are acetone, hydrogen cyanide, and sulfuric acid. The acetone and HCN are reacted under alkaline conditions to produce the cyanohydrin. Reaction of the cyanohydrin with sulfuric acid ultimately produces methacrylamide sulfate, hydrolysis of which produces methacrylic acid. Methyl methacrylate can be made either by esterifying the acid or directly by reacting the amide sulfate with methanol. 

Ethylene Cyanohydrin. This cyanohydrin, also known as hydracrylonitnle or glycocyanohydrin [109-78-4] is a straw-colored Hquid miscible with water, acetone, methyl ethyl ketone, and ethanol, and is insoluble in benzene, carbon disulfide, and carbon tetrachloride. Ethylene cyanohydrin differs from the other cyanohydrins discussed here in that it is a P-cyanohydrin. It is formed by the reaction of ethylene oxide with hydrogen cyanide. 

The reaction of 17-keto steroids with hydrogen cyanide (or acetone cyanohydrin) to form a mixture of the 17-cyano-17-hydroxy compounds, followed by dehydration and reaction with methyl Grignard reagent, is one of the earliest methods for the conversion of androstanes to pregnanes. 

The use of acetone cyanohydrin (in an exchange reaction) instead of alcoholic hydrogen cyanide affords even higher yields of 17-cyanohydrins and the former reagent has the added advantage of reacting quantitatively and essentially selectively with the 17-ketone of androst-4-ene-3,17-dione. Sodium hydroxide promotes the exchange reaction in some cases. 

The formation of adducts of enamines with acidic carbon compounds has been achieved with acetylenes (518) and hydrogen cyanide (509,519,520) (used as the acetone cyanohydrin). In these reactions an initial imonium salt formation can be assumed. The addition of malonic ester to an enamine furnishes the condensation product, also obtained from the parent ketone (350,521). 

Hydrogen cyanide is a reactant in the production of acrylonitrile, methyl methacrylates (from acetone), adiponitrile, and sodium cyanide. It is also used to make oxamide, a long-lived fertilizer that releases nitrogen steadily over the vegetation period. Oxamide is produced by the reaction of hydrogen cyanide with water and oxygen using a copper nitrate catalyst at about 70°C and atmospheric pressure ... 

A very efficient and universal method has been developed for the production of optically pue L- and D-amino adds. The prindple is based on the enantioselective hydrolysis of D,L-amino add amides. The stable D,L-amino add amides are effidently prepared under mild reaction conditions starting from simple raw materials (Figure A8.2). Thus reaction of an aldehyde with hydrogen cyanide in ammonia (Strecker reaction) gives rise to the formation of the amino nitrile. The aminonitrile is converted in a high yield to the D,L-amino add amide under alkaline conditions in the presence of a catalytic amount of acetone. The resolution step is accomplished with permeabilised whole cells of Pseudomonas putida ATCC 12633. A nearly 100% stereoselectivity in hydrolysing only the L-amino add amide is combined with a very broad substrate spedfidty. 

The aqueous solution contains a-morpholinoisobutyronitrile in the form of its hydrochloride. It is formed by condensation of morpholine with the acetone and hydrogen cyanide formed in the nitration reaction. It is because of this side reaction that the excess amine is employed. 

Acetone cyanohydrin nitrate will not nitrate amines with branching on the carbon a to the nitrate group. For these substrates the use of ethyl nitrate and lithium bases is favoured. a-Aminonitriles are frequently observed as impurities under the reaction conditions because of the slow decomposition of acetone cyanohydrin nitrate to hydrogen cyanide and acetone. The need for an excess of amine during these reactions is wasteful and only practical if this component is cheap and widely available. Other cyanohydrin nitrates are less efficient N-nitrating agents. ... 

The only method used in the U.S. for the production of methyl methacrylate is the acetone cyanohydrin process. Acetone cyanohydrin (from the reaction of acetone with hydrogen cyanide) is reacted with sulfuric... 

Acetone cyanohydrin is manufactured by the direct reaction of hydrogen cyanide with acetone catalyzed by base, generally in a continuous process. 

All initiators are potentially explosive compounds and must be stored and handled with care. 2,2 -AIBN is obtained from the reaction of acetone with potassium cyanide and hydrazine hydrochloride. As shown in equation 17.51, the reaction produces hydrogen cyanide and hydrazine. The latter reacts with acetone forming acetone dihydrazone, which reacts with... 

The most frequently used method for the preparation of isoquinoline Reissert compounds is treatment of an isoquinoline with acyl chloride and potassium cyanide in water or in a dichloromethane-water solvent system. Though this method could be successfully applied in a great number of syntheses, it has also some disadvantages. First, the starting isoquinoline and the Reissert compound formed in the reaction are usually insoluble in water. Second, in the case of reactive acyl halides the hydrolysis of this reaction partner may became dominant. Third, the hydroxide ion present could compete with the cyanide ion as a nucleophile to produce a pseudobase instead of Reissert compound. To decrease the pseudobase formation phase-transfer catalysts have been used successfully in the case of the dichloromethane-water solvent system, resulting in considerably increased yields of the Reissert compound. To avoid the hydrolysis of reactive acid halides in some cases nonaqueous media have been applied, e.g., acetonitrile, acetone, dioxane, benzene, while utilizing hydrogen cyanide or trimethylsilyl cyanide as reactants instead of potassium cyanide. 

Methacrylic acid has been used for the synthesis of polyfmethyl methacrylate). It has been synthesized industrially via a reaction of acetone with hydrogen cyanide (12, 17, 330, 331). However, the process produces ammonium bisulfate and uses the toxic hydrogen cyanide. Recently, an alternative, a two-step oxidation of isobutylene, has been developed. The first step is the oxidation of isobutylene to methacrolein, and the second is the oxidation of methacrolein to methacrylic acid ... 

Hydrogen cyanide, a by-product of acrylonitrile manufacture, has its primary use in the manufacture of methyl methacrylate by reaction with acetone. 

As an example of this effect, the equilibrium constant for the reaction of acetone with hydrogen cyanide is 32, whereas the equilibrium constant for a similar reaction of acetophenone is 0.77 ... 

Linder typical conditions the reaction of acetone with hydrogen cyanide (K = 32) has most of the reactants converted to the product at equilibrium. This allows the cyanohydrin to be obtained in acceptable isolated yield (78%). In contrast, the amount of cyanohydrin product that is present at equilibrium in the reaction of acetophenone (K = 0.77) is too low for the reaction to be synthetically useful unless some method is used to drive the equilibrium toward the product. 

Ruthenium(II) Treatment of [Ru(NH3)5(OH2)]2+ or [Ru(NH3)5(acetone)]2+ with L or [RuCl(NH3)5]2+ with zinc amalgam in the presence of L yields [RuL(NH3)5]2+ (L = acetonitrile, benzonitrile,358 substituted benzonitrile,196 358 359 acrylonitrile,360 hydrogen cyanide,36,37 ethyl cyano-formate,361 dicyanamide, malononitrile, substituted malononitrile, tricyanomethanide,362 4-cyano-l-methylpyridinium196). Reaction of a hundred-fold excess of RCHO (R = Ph, Me) with [Ru(NH3)6]2+ under alkaline conditions yields [Ru(NH3)sNCR]2+.363-365 The likely mechanism of this reaction is given in Scheme 12. An alternative route to nitrile complexes is by reaction of [Ru(NH3)sOH2]2+ with aldoximes, e.g. RMeC=NOH, to afford [Ru(NH3 )5 (NCMe)]2 + and... 

The reaction of carbon nucleophiles with the electron-deficient carbon of a carbonyl group represents one of the major ways of making C--C bonds. The addition of hydrogen cyanide to acetone to form the cyanohydrin g 3,15) was one of the first reactions to be studied mechanistically. The reversible reaction leads to the cyanohydrin in which the cyano group may be further modified by hydrolysis to a carboxylic acid or by reduction to an amine. 

The formation of enamines from acyclic methyl ketones is often complicated by reaction of the enamine with the ketone. In a cleverly devised process, Ahlbrecht first converted acetone to a cyatwamine, which is then transformed into the enamine by potassium r-butoxide induced loss of hydrogen cyanide (equation 9). ... 

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