Ethyl chloride coupling

Higher ethyl chloride efficiency is claimed for a process utilising a hydrocarbon diluent coupled with stepwise addition of sodium hydroxide (80). Product work-up includes distillation to remove residual unreacted ethyl chloride, added diluent, methanol, and diethyl ether neutralization of excess sodium hydroxide washing in water to remove salts drying and grinding. 

It is likely that ethyl chloride, formed as an intermediate upon the interaction of ethanol with HCI (the latter originates from coupling 1,3-diketones with TeCl4), plays an important role. This conclusion is con-... 

Fig. 24. Schematic effect of dihedral angle the magnitude of the coupling constant for vicinal protons, Ji,2i or the half-wave potentials for the reduction of cyclic vicinal dibromides (polarographio debromination), A = — JBj/2 (volts vs. S.C.E.) or A = 2D2, the sum of the squares of the displacement of the atoms in dehydrochlorination of ethyl chloride by PLM.

As a final point, consider the observed behavior of the major product yields with increasing ethyl chloride decomposition (Figure 7). The dichlorobutane yield is essentially constant with an increase in the absorbed radiation dose, while the ethane yield rises sharply and the ethylene-acetylene product is substantially reduced. These observations suggest the occurrence of additional reaction processes other than those already suggested. Also, the fact that the ethane increase is not matched by the ethylene decrease indicates that these two phenomena are not necessarily coupled. The most likely explanation is that ethylene is attacked by Cl atoms,... 

Exploration of alkaline earth/metal oxide catalysts and other metal/metal oxide catalysts has been continued at Union Carbide. As an example, after over 350 hours of methane coupling with a 5 wt% barium carbonate on titanium oxide (with ethyl chloride in the feed gas), a C2 yield of 22%, a Cj selectivity of 58%, and an ethylene/ethane ratio of 8 1 were obtained. The coupling catalysts were comparable in selectivity, activity, and Cj yield to the better literature catalysts, but provide hundreds of hours of stable operation in the oxidation of methane to Cj s. These catalysts require the presence of a small amount of halides, either as a catalyst component or as a periodic or continuous additive to the catalyst. The chloride appears to serve three distinct roles, resulting in suppression of carbon dioxide formation, increased rates to Cg products, and higher ethylene-to-ethane product ratios. There have been numerous other recent reports. 

The CuCN 2LiBr solution was cooled to -40°C and transferred into the LiNap with a cannula. The solution was stirred for 5 min. The active copper solution was warmed to -35°C and charged with ethyl 4-bromobutyrate (1.95 mmol). For aryl halides the solution was warmed to 0°C, immediately charged with the aryl halide, and allowed to mix for 1 h. The solution was stirred for 10 min and was ready to use for acid chloride couplings or conjugate additions. 

Alkylation of phenol couplings is commonly practiced in dye chemistry to eliminate the acid/basic sensitivity of the dye. In addition to o-alkylation with ethyl chloride, dimethyl-sulfate and diethylsulfate are used. The latter is preferred to the toxic dimethylsulfate. 

The ester 870 is prepared by the cross-coupling of the chloroformate 869 with an organotin reagent. Some chloroformates are easily decomposed by a Pd catalyst, and hence the reaction should be carried out by slow addition of the chloroformates. Similarly, the amide 872 is prepared by the reaction of the carbamoyl chloride 871 [742]. The coupling of alkylcopper with ethyl chloroformate catalyzed by Pd affords esters[743]. 

Piperazine, N-alkylation with benzyl chloride, 42, 19 Piperazine, 1-benzyl-, 42,19 Piperidine, addition to ethylene, 43, 45 as catalyst for Claisen-Schmidt condensation, 41, 40 Piperidine, 1-ethyl-, 43, 45 Piperidine, 1-(2-naphthyl)-, 40,74 Pivalic acid, oxidative coupling to a,a,-a, a -tetramethyladipic add, 40, 92... 

Ethyl acetate is an oxygenated solvent widely used in the inks, pharmaceuticals and fragrance sectors. The current global capacity for ethyl acetate is 1.2 million tonnes per annum. BP Chemicals is the world s largest producer of ethyl acetate. Conventional methods for the production of ethyl acetate are either via the liquid phase esterification of acetic acid and ethanol or by the coupling of acetaldehyde also known as the Tischenko reaction. Both of these processes require environmentally unfriendly catalysts (e.g. p-toluenesulphonic acid for the esterification and metal chlorides and strong bases for the Tischenko route). In 1997 BP Chemicals disclosed a new route to produce ethyl acetate directly from the reaction of ethylene with acetic acid using supported heteropoly acids... 

Diazotised 5-aminotetrazole is unstable under the conditions recommended for its use as a biochemical reagent. While the pH of the diazotised material (the cation of which contains 87% nitrogen) at 0°C was being reduced to 5 by addition of potassium hydroxide, a violent explosion occurred [1], This may have been caused by a local excess of alkali causing the formation of the internal salt, 5-diazoniotetrazolide, which will explode in concentrated solution at 0°C [2], The diazonium chloride is also very unstable in concentrated solution at 0°C. Small-scale diazotisation (2 g of amine) and susequent coupling at pH 3 with ethyl cyanoacetate to prepare ethyl 2-cyano-(l//-tetrazol-5-ylhydrazono)acetate proceeded uneventfully, but on double the scale a violent explosion occurred [3], The importance of adequate dilution of the reaction media to prevent explosions during diazotisation is stressed [4]. 

The procedure described is essentially that of Ballard and Dehn.1 Stilbene has also been prepared by reduction of desoxy-benzoin,20 benzaldehyde,23 and benzil 2o-2c by dehydrogenation of ethyl benzene,30 toluene,30- 33- 3, and bibenzyl 33-3alkaline reduction of phenylnitromethane,40 phenylnitroacetonitrile,40 and desoxybenzoin 43 by distillation of benzyl sulfone,50 benzyl sulfide,60-63 calcium cinnamate,5 cinnamic acid,5d phenyl cinna-mate,6e-6/ and diphenyl fumarate ie by dehydrohalogenation of a,a -dichlorobibenzyl60 and benzyl chloride 63 by dehalogenation of a,a,c/,a -tetrachlorobibenzyl70 and benzal chloride 73 by the coupling of cinnamic acid and phenyldiazonium chloride 8 by de-... 

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