Miscellaneous Hydrogenations

Hydrogenation of nitro compounds can be achieved with [ HCo(CN)-,[ as catalyst however, in many cases (especially with nitroarenes), products of reductive dimerization, i.e., azo and hydrazo compounds, are formed instead of the expected amino derivatives [12]. Ketoximes and oximes of 2-oxo acids are hydrogenated to amines [142], 2-Amino acids can be prepared in high yields by reductive animation of 2-oxo acids in an aqueous NH3 solution (Eq. 41) [143], 

Catalytic hydrogenation of chloronitroaromatics is often accompanied by dehalo-genation. Importantly, in DMSO-containing water, the [Pd(OAc)2] +TPPTS catalyst hydrogenated 5-chloro-2-nitrophenol to 5-chloro-2-aminophenol with outstanding selectivity [168]. 

Anilines can be obtained from nitroarenes under water-gas shift (WGS) conditions (Eq. 42). 

In most cases such reactions are conducted in strongly alkaline aqueous solutions [144] or in the presence of amines [145, 146], [Rh6(CO)16], [Rh12(CO)30]2 and [Rh5(CO)15], formed in situ in the reaction mixture, are among the most active catalysts [147]. However, addition of a strong base to solutions of [Rh(CO)4] (with K+, Cs+, or (PPh3)2N+ cation) diminishes the catalytic activity in the hydrogenation of nitrobenzene to aniline with CO + H20 [148]. Recently it was disclosed that the catalysts prepared from PdCl2 and TPPTS or multiply-sulfonated BINAP 

A similarly selective reduction of nitroarenes was achieved under WGS conditions by using [ Ru3(CO)12] in the presence of certain amines, such as diisopropylamine, piperidine, dibutylamine, and triethylamine [146]. Importantly, the latter reaction yielded no unwanted H2 as by-product from a concomitant WGS reaction. 

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A hst of 74 GLS reacdions with hterature references has been compiled by Shah Gas-Liquid-Solid Reactions, McGraw-HiU, 1979), classified into groups where the solid is a reactant, or a catalyst, or inert. A hst of 75 reactions made by Ramachandran and Chaudhari (Three-Phase Chemical Reactors, Gordon and Breach, 1983) identifies reactor types, catalysts, temperature, and pressure. They classify the processes according to hydrogenation of fatty oils, hydrodesulfurization, Fischer-Tropsch reactions, and miscellaneous hydrogenations and oxidations. 

After learning that we could achieve the same results as the Japanese by using stabilized lignin tar as the pasting oil, we made a number of miscellaneous hydrogenation runs. The results of some of these are shown in Table II. 

Miscellaneous Reactions. Sodium bisulfite adds to acetaldehyde to form a white crystalline addition compound, insoluble in ethyl alcohol and ether. This bisulfite addition compound is frequendy used to isolate and purify acetaldehyde, which may be regenerated with dilute acid. Hydrocyanic acid adds to acetaldehyde in the presence of an alkaU catalyst to form cyanohydrin the cyanohydrin may also be prepared from sodium cyanide and the bisulfite addition compound. Acrylonittile [107-13-1] (qv) can be made from acetaldehyde and hydrocyanic acid by heating the cyanohydrin that is formed to 600—700°C (77). Alanine [302-72-7] can be prepared by the reaction of an ammonium salt and an alkaU metal cyanide with acetaldehyde this is a general method for the preparation of a-amino acids called the Strecker amino acids synthesis. Grignard reagents add readily to acetaldehyde, the final product being a secondary alcohol. Thioacetaldehyde [2765-04-0] is formed by reaction of acetaldehyde with hydrogen sulfide thioacetaldehyde polymerizes readily to the trimer. 

The most frequentiy used halo alkylating agents are aldehydes and hydrogen haUdes, haloalkyl ethers, haloalkyl sulfides, acetals and hydrogen haUdes, di- and polyhaloalkanes, haloalkenes, haloalcohols, haloalkyl sulfates, haloalkyl -tosylates, and miscellaneous further haloalkyl esters. Haloalkylations include halomethylation, haloethylation, and miscellaneous higher haloalkylations. Under specific conditions, bis- and polyhaloalkylation can also be achieved. 

Miscellaneous. Hydrochloric acid is used for the recovery of semiprecious metals from used catalysts, as a catalyst in synthesis, for catalyst regeneration (see Catalysts, regeneration), and for pH control (see Hydrogen-ION activity), regeneration of ion-exchange (qv) resins used in wastewater treatment, electric utiUties, and for neutralization of alkaline products or waste materials. In addition, hydrochloric acid is also utilized in many production processes for organic and inorganic chemicals. 

Miscellaneous Reactions. Ahyl alcohol can be isomerized to propionaldehyde [123-38-6] in the presence of sohd acid catalyst at 200—300°C. When copper or alumina is used as the catalyst, only propionaldehyde is obtained, because of intramolecular hydrogen transfer. On the other hand, acrolein and hydrogen are produced by a zinc oxide catalyst. In this case, it is considered that propionaldehyde is obtained mainly by intermolecular hydrogen transfer between ahyl alcohol and acrolein (31). 

Miscellaneous Reactions. The A/-hydrogen atom of diphenylamine is reactive and readily replaced by deuterium by treating with C2H OD. The addition of acid cataly2es the exchange of the hydrogen atoms on the ring system (11). 

Miscellaneous Derivatives. Other derivatives of toluene, none of which is estimated to consume more than ca 3000 t (10 gal) of toluene aimuaHy, are mono- and dinitrotoluene hydrogenated to amines ben2otrich1 oride and chlorotoluene, both used as dye intermediates / 7-butylben2oic acid from / 7-butyltoluene, used as a resin modifier dodecyltoluene converted to a ben2yl quaternary ammonium salt for use as a germicide and biphenyl, obtained as by-product during demethylation, used in specialty chemicals. Toluene is also used as a denaturant in specially denatured alcohol (SDA) formulas 2-B and 12-A. 

Miscellaneous Reactions. Epoxy compounds yield chlorosubstituted carbonates (45). The reaction of chloroformates with hydrogen peroxide or metal peroxides results in the formation of peroxydicarbonates that are used as free-radical initiators of polymerization of vinyl chloride, ethylene, and other unsaturated monomers (46,47). 

Miscellaneous. 1,1,1-Trichloroethane reacts with olefins, CH2=CRR, in the presence of P(0)[(NCH2)]3 and FeCl2 at 130°C, to give compounds of the type CH2CCl2CH2CRR Cl (61). Fluorination of 1,1,1-trichloroethane with anhydrous hydrogen fluoride at 144°C gives both... 

Heating a mixture of tetrachloroethane vapors and chlorine over active charcoal at 400°C gives carbon tetrachloride and hydrogen chloride (125). Miscellaneous. Air oxidation of 1,1,2,2-tetrachloroethane under ionizing radiation gives dichloroacetyl chloride (117). Contact of... 

Miscellaneous Reactions. Ethylene oxide is considered an environmental pollutant. A study has determined the half-life of ethylene oxide ia the atmosphere (82,83). Autodecomposition of ethylene oxide vapor occurs at - 500° C at 101.3 kPa (1 atm) to give methane, carbon monoxide, hydrogen, and ethane (84—86). 

The increasing ranges of pressure and temperature of interest to technology for an ever-increasing number of substances would necessitate additional tables in this subsection as well as in the subsec tion Thermodynamic Properties. Space restrictions preclude this. Hence, in the present revision, an attempt was made to update the fluid-compressibihty tables for selected fluids and to omit tables for other fluids. The reader is thus referred to the fourth edition for tables on miscellaneous gases at 0°C, acetylene, ammonia, ethane, ethylene, hydrogen-nitrogen mixtures, and methyl chloride. The reader is also... 

In the chemical process industry molybdenum has found use as washers and bolts to patch glass-lined vessels used in sulphuric acid and acid environments where nascent hydrogen is produced. Molybdenum thermocouples and valves have also been used in sulphuric acid applications, and molybdenum alloys have been used as reactor linings in plant used for the production of n-butyl chloride by reactions involving hydrochloric and sulphuric acids at temperatures in excess of 170°C. Miscellaneous applications where molybdenum has been used include the liquid phase Zircex hydrochlorination process, the Van Arkel Iodide process for zirconium production and the Metal Hydrides process for the production of super-pure thorium from thorium iodide. 

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