2- ETHYLHEXANAL

MIBK is a flammable, water-white Hquid that boils at 116°C. It is sparingly soluble in water, but is miscible with common organic solvents. It forms an a2eotrope with water as shown in Table 2. Condensation of MIBK with another methyl ketone can produce ketones containing 9—15 carbons. For example, condensation with acetone produces diisobutyl ketone, and self-condensation of two MIBK molecules produces 2,6,8-trimethyl-4-nonanone [123-17-1]. Condensation with 2-ethylhexanal gives 1-tetradecanol (7-ethyl-2-methyl-4-undecanol), avaluable surfactant intermediate (58). 

Reaction of 2,4-diorgano-l,3-diols, such as 2-ethylhexane-l,3-diol, with TYZOR TPT in a 2 1 molar ratio gives the solvent soluble titanate complex, TYZOR OGT [5575-43-9] (4) (73). If the reaction is conducted in an inert solvent, such as hexane, and the resultant slurry is treated with an excess of water, an oligomeric hydrolysis product, also solvent-soluble, is obtained (74). 

Ethylhexanal, the reduced aldol condensation product of //-butyraldehyde, is converted into 2-ethylhexanoic acid [149-57-5] which is converted primarily into salts or metal soaps. These are used as paint driers and heat stabili2ers for poly(vinyl chloride). 

Additional evidence that a dynamic equilibrium exists between an enamine, N-hemiacetal, and aminal has been presented by Marchese (41). It should be noted that no acid catalysts were used in the reactions of aldehydes and amines discussed thus far. The piperidino enamine of 2-ethylhexanal (0.125 mole), morpholine (0.375 mole), and p-toluene-sulfonic acid (1.25 x 10 mole) diluted with benzene to 500 ml were refluxed for 5 hr. At the end of this time the enamine mixture was analyzed by vapor-phase chromatography, which revealed that exchange of the amino residue had occurred in a ratio of eight morpholine to one piperidine. Marchese proposed a scheme [Eqs. (4), (5) and (6)] to account for these... 

The n-butyraldehyde is treated with a 2 per cent w/w aqueous sodium hydroxide and undergoes an aldol condensation at a conversion efficiency of 90 per cent. The product of this reaction, 2-ethylhexanal, is separated and then reduced to 2-ethylhexanol by hydrogen in the presence of a Raney nickel catalyst with a 99 per cent conversion rate. In subsequent stages of the process (details of which are not required), 99.8 per cent of the 2-ethylhexanol is recovered at a purity of 99 per cent by weight. 

Ethylhexan-1 -ol is a useful building block for the pharmaceutical, food, cosmetic and chemical industries. The reduction of 2-ethylhex-2-enal to CS )-2-ethylhexan-l -ol by baker s... 

Huang, Y., Zhang, F. and Gong, Y. (2005) A convenient approach to (S)-2-ethylhexan-l-ol mediated by baker s yeast. Tetrahedron Letters, 46, 7217-7219. 

Commercially available 2-ethylhexanal (Eastman practical grade) is purified by fractional distillation b.p. 163-163.2°/atm., no 1.4133. Other aldehydes are conveniently prepared by the Rosenmund reduction.2 If the aldehyde is relatively unstable toward autoxidation,3 a catalytic amount (0.5-1.0 g.) of hydroquinone is added with the aldehyde-bromo ester solution. 

Pd supported overlarge-pore tridimensional acidic zeolites such as HFAU are the more active and selective catalysts for the synthesis of bulkier ketones. Thus, in a 0.2% Pd-HFAU catalyst, yield and selectivity from cyclohexanone of 23 and 75% can be obtained in cyclohexylcyclohexanone synthesis. Furthermore, the S5mthesis of aldehydes can only be made selective by joining the hydrogenating metaUic sites (Pd) to basic sites (instead of acidic sites). Thus, 2-ethylhexanal, which is a component of perfumes and fragrances, can be synthesized with high yield and selectivity (64 and 91%, respectively) on a PdKX zeolite. Much lower yields and selectivities are obtained over nonzeolitic materials, such as Pd/MgO. 

Synonyms BRN 1730777 1,2-Dimethylhexane EINECS 209-660-6 2-Ethylhexane 5-Methyl-heptane NSC 24845. 

The oxidation of 2-ethylhexan-l-ol to 2-ethyl-hexanal by the Oppenauer oxidation with aliphatic aldehydes such as acetaldehyde, propionaldehyde, and isobutyr-aldehyde has been investigated with gas-phase reactants and MgO as the catalyst (196). Reaction with propionaldehyde was found to be an effective synthetic route for 2-ethylhexanal preparation, whereas with acetaldehyde and isobutyraldehyde a gradual catalyst deactivation in a flow reactor was observed. 

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