Industrial process for the conversion

Alcohols and carboxylic acids also readily add to metal-activated alkenes2 and industrial processes for the conversion of ethylene to vinyl acetate, vinyl ethers and acetals are well established. However, very little use of intermolecular versions of this chemistry with more complex alkenes has been developed. In... 

SCHEME 2. Antibioticos industrial process for the conversion of Cephalosporin C in fermentation broths to 7-ACA. 

An important industrial process for the conversion of organic precursors to fully fluorinated derivatives (perfluo-rocarbon compounds) is the Simons Process. The Simons Process [1-9] uses an electrochemical cell to oxidize per-hydro-organic materials, at a nickel anode, to their perfluoro-relatives. The electrolyte for that process is liquid anhydrous hydrogen fluoride in which sodium fluoride, or other ionizing solutes, are dissolved (the latter, to provide for electrical conductance). 

Scheme IX. 1. Industrial process for the conversion of cyclohexane to adipic...

It is important that chemical engineers master an understanding of metabolic engineering, which uses genetically modified or selected organisms to manipulate the biochemical pathways in a cell to produce a new product, to eliminate unwanted reactions, or to increase the yield of a desired product. Mathematical models have the potential to enable major advances in metabolic control. An excellent example of industrial application of metabolic engineering is the DuPont process for the conversion of com sugar into 1,3-propanediol,... 

Development of the industrial process for electrochemical conversion of acrylonitrile to adiponitrile led to extensive investigation into the mechanism of the dimerization process. Reactions of acrylonitrile radical-anion are too fast for investigation but the dimerization step, for a number of more amenable substrates, has been investigated in aprotic solvents by electrochemical techniques. Pulse-radiolysis methods have also been used to study reactions in aqueous media. 

More comprehensive discussions of considerations relevant to the development of viable industrial processes for the catalytic conversion of epoxides and C02 are included in the reviews of Keurentjes and coworkers [67], and Luinstra [68]. 

Oxidative dehydrogenation of alcohols is a new approach in the development of industrial processes for the synthesis of aldehydes and ketones [103-105], In this regard, the technologically most suitable is the method of acetaldehyde synthesis in the presence of melted vanadium oxide, alkaline metals with promoting additives, alkaline metal sulfates or chlorides as catalysts [105], The target product yield equals 65.9% per used alcohol at 69.2% conversion. The disadvantage of the method is the relatively low yield of the target product... 

An important goal is, therefore, to develop effective methods for catalytic oxidations with dioxygen, under mild conditions in the liquid phase. Two substrates which are often chosen as models for alkane oxidations are cyclohexane and adamantane. Cyclohexane is of immense industrial importance as its oxidation products - cyclohexanone and adipic acid - are the raw materials for the manufacture of nylon-6 and nylon-6,6. Adamantane is an interesting substrate as the ratio of oxidation at the secondary versus the tertiary C-H bonds is used as a measure of radical versus nonradical oxidation pathways. Industrial processes for the oxidation of cyclohexane, to a mixture of cyclohexanol and cyclohexanone, generally involve low conversions (under 10%). Even at such low conversions, selectivities are modest (70-80%) and substantial amounts of overoxidation products, mostly dicarboxylic acids, are formed. 

Enzymatic Kinetic Resolution of N-Acyl Amino Acids Coupled with Racemization by N-Acyl Amino Acid Racemase Acylases are enzymes hydrolysing the N-acetyl derivatives of amino acids. They require the free carboxylate for activity and have long been used for the kinetic resolution of amino acids. The unreacted enantiomer is usually racemized in a separate step by treatment with acetic anhydride. While acylases from hog kidney have an L-specificity, bacterial acylases with L- and D-specificity of various origins have been isolated and used for the kinetic resolution of N-acetyl amino acids. An industrial process for the production of L-Met and other proteinogenic and non-proteinogenic L-amino acids such as L-Val, L-Phe, L-Norval, or L-aminobutyric acid has been established. Currently, several hundred tons per year of L-methionine are produced by this enzymatic conversion using an enzyme membrane reactor [46]. 

Efficient processes for the conversion of 2,2-dichloro-l,3-benzodioxole to the 2,2-difluoro analogue have been the subject of industrial interest and generally involve treatment with a metal fluoride and a catalyst in sulfolane <84GEP3315147, 87GEP3642256, 91euP423009>. The 2,2-difluoro compound can also be prepared from the thione (12) by reaction with NIS and Bu N H2F3 <94SL251>. 

In the industrial utilization of this process for the conversion of carbon monoxide to carbon dioxide with formation of an equivalent amount of hydrogen, catalysts of iron promoted with oxides of cerium, aluminum, etc., are employed.64... 

The hydrolysis of aliphatic and aromatic nitriles into amides and/or carboxylic acids is an area of rapidly increasing interest. Already the Nitto Chemical Industry Co. Ltd. has developed a large-scale process for the conversion of acrylonitrile into acrylamide using Rhodococcus cells (see Section 6.7.2). Many other organisms, as well as the nitrilases, nitrile hydratases and amidases derived from them, can effect similar conversions. It is interesting to note that for dinitriles, only one of the nitrile groups... 

---