Butyronitrile, hydrogenation

Figure 3.8 Activity of conventional and colloidal Rh/C catalysts, eventually doped with 2% colloidal Ti(0), compared in the butyronitrile hydrogenation test (2d). (Adapted from Bonnemann, H. and Brijoux, W., in Surfactant-Stabilized Nanosized Colloidal Metals and Alloys as Catalyst Precursors/Advanced Catalysts and Nanostructured Materials, Moser, W., Ed., Academic Press, San Diego, 1996, pp. 165-196, Chap. 7. With permission from Elsevier Science.)...

NMR lineshape analysis, 39 376-378 Butyronitrile, hydrogenation over Raney-type nickel catalysts, 36 370... 

The rate of butyronitrile hydrogenation was determined in the trickle phase with a 120-ml tubular reactor using 20 ml of either 3-mm activated tablets or hollow spheres. This hydrogenation was performed at 40 bar hydrogen pressure, 75°C, and at LHSV of 0.6 h" with a 20 wt.% butyronitrile in methanol solution. Butyronitrile conversion and selectivities were determined by GC. 

Figure 2. Activity of Rh/C catalysts in the butyronitrile hydrogenation test.

By using surfactant-stabilized rhodium (5% on charcoal) in the butyronitrile hydrogenation test, we were able to demonstrate that the activity of supported metal colloids was superior to that of conventional salt-impregnation catalysts with the same metal loading (see Fig. 2). Further significant enhancement of the activity was achieved by doping the noble metal precursor with 0.2% colloidal Ti(O). ... 

Tii3-nanoclusters (Fig. 2.8) have been used as powerful activators for heterogeneous noble metal hydrogenation catalysis [9, 130]. In the so-called butyronitrile hydrogenation standard test the activity of surfactant-stabiUzed colloidal rhodium... 

The advantage of the supported colloid-catalyst is demonstrated by comparison of the activity of three Rh-catalysts (5 % on charcoal) in the butyronitrile-hydrogenation-test ... 

Ni/N-CNTs 3.0-3.9 Butyronitrile hydrogenation Higher electron density delivered by nitrogen on the surface of CNTs leading to an enhanced catalytic activity [119]... 

Catalysts show remarkable product variation in hydrogenation of simple nitriles. Propionitrile, in neutral, nonreactive media, gives on hydrogenation over rhodium-on-carbon high yields of dipropylamine, whereas high yields of tripropylamine arise from palladium or platinum-catalyzed reductions (71). Parallel results were later found for butyronitrile (2S) and valeronitrile (74) but not for long-chain nitriles. Good yields of primary aliphatic amines can be obtained by use of cobalt, nickel, nickel boride, rhodium, or ruthenium in the presence of ammonia (4J 1,67,68,69). 

A mixture of 23 parts of the ethyl ester of 4 phenylisonipecotic acid and 15 parts of 2,2-diphenyl-4-bromobutyronitrile in 19 parts of xylene is heated for 24 hours at 100°-120°C and then cooled and filtered to remove the precipitate of the hydrobromide of the ethyl ester of 4-phenylisonipecotic acid. The filtrate is then extracted with dilute hydrochloric acid and the extract is rendered alkaline by addition of concentrated aqueous potassium hydroxide and extracted with ether. This ether extract is treated with gaseous hydrogen chloride. The resulting precipitate is collected on a filter. The hydrochloride of the ethyl ester of 2,2 diphenyl-4-(4 -carboxy-4 -phenyl-1 -piperidino) butyronitrile thus obtained melts at about 220.5-222°C. See Meperidine hydrochloride for synthesis of 4-phenyl-isonipecotic acid ethyl ester. 

Synthesis (Cavalla and White (Wyeth), 1969 1969 Bradley 1980 Kleemann et al. 1999) By condensation of 2-(m-methoxyphenyl)butyronitrile with ethyl 4-iodobutyrate by means of NaNH2 in liquid NH3 to give ethyl 5-cyano-5-(m-methoxyphenyl)heptanoate, which is cyclized by hydrogenation with H2 over Raney Ni in cyclohexane to yield 6-ethyl-6-(m-methoxyphenyl)hexahydro-2H-azepin-2-one this ketone is reduced with LiAIH4 in THF to 3-ethyl-3-(m-methoxyphenyl)hexahydro-IH-azepine, which in turn, is reductively methylated with HCHO, H2 and Pd/C in ethanol to give 1-methyl-3-ethyl-3-(m-methoxyphenyl)-hexahydro-1H-azepine, and finally demethylated by refluxing with 80% HBr to yield a racemic mixture of the final product. 

To promote the activity and selectivity of Raney nickel catalysts, alloying of the starting Ni-Al alloy with metal was often used. For instance, Montgomery (ref. 4) prepared catalysts by activating ternary alloy powders of Al (58 wt %)-Ni (37-42 wt %) - M (0.5 wt %) where M = Co, Cr, Cu, Fe and Mo. All promoted catalysts tested were more active than the reference catalyst, in hydrogenation of butyronitrile. Molybdenum was the most effective promoter. With Cr or Ti, hydrogenation of isophtalonitrile on Raney nickel occurred at lower optimum temperature than with non activated nickel (ref. 5). It was shown that addition of Ti or Co to Raney nickel suppressed the formation of secondary amine (ref. 6). 

Fig. 17.12 Evolution of hydrogen from a double phase system. The aqueous solution (8.0 ml) contained 2 M potassium bromide and Ti02 powder (120 mg). The n-butyronitrile solution (1.7 ml) contained DDHQ (1.0 x 10-3 M). During the photocatalytic reaction, only the aqueous phase was photoirradiated. The inset shows the spectral change of the n-butyronitrile solution by photoirradiation for 1500 min, indicating that DDHQ was converted into DDQ.

Hydrogenation of aliphatic nitriles over platinum metal catalysts often results in ex-tensive formation of secondary and tertiary amines. For example, hydrogenation of butyronitrile over Rh-C in water at 100-125°C and 2.76-4.14 MPa H2 gave a mixture of 51.5% of butylamine and 48.5% of dibutylamine, while in hydrogenation with addition of ammonia (167 mol% based on butyronitrile) dibutylamine was formed quantitatively. Under similar conditions the hydrogenations with Pd-C and Pt-C gave tributylamine in yields exceeding 95%.7... 

H—C may be assumed to be in the range of 4—5 kJ/mol. Moreover, Saum has own that the remarkable increase of the boiling point of nitriles, as compared with hydrocarbons of the same size, is nearly the same for normal, secondary, or tertiary butyronitrile since the increase of boiling point is evidently due to association, and since tertiary butyronitrile does not have a hydrogen at the a-carbmi atom, hydrogen bonding can be excluded as the cause of the association. 

Acrylonitrile is a colourless liquid with a boiling point of 77-3 C and is sparingly soluble in water. It polymerizes readily in aqueous solution in the presence of a suitable catalyst such as benzoyl peroxide, azo-2-2 -di-iso-butyronitrile, or ferrous sulphate and hydrogen peroxide. Polymerization... 

Hydrogenation of butyronitrile derivative 6 over platinum oxide in acidic medium yields quinolizidine 7, by reduction of the pyridine ring first and piperidone derivative 8 by reduction of the cyano group ... 

The chlorination of the surface can also be achieved by a controlled radical process at moderate temperatures. To this end, thionyl chloride is reacted in suspension with the previously hydrogenated nanodiamond in the presence of AIBN (azo-bis-iso-butyronitrile. Figure 5.33). A surface covering of ca. 3.5mmolg is attained, which almost comes up to a complete monolayer (Figure 5.34). 

BUTYRONITRILE (109-74-0) Forms explosive mixture with air (flash point 79°F/26°C oc). Contact with steam or hot surfaces forms hydrogen cyanide gas. Exothermic reaction with strong acids (liberating hydrogen cyanide gas) or strong oxidizers. May accumulate static electrical charges may cause ignition of its vapors. 

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