Isobutyraldehyde—continued

Isomorphous replacement in isotactic polyaldehydes was shown by A. Tanake, Y. Hozumi, K. Hatada, S. Endo, and R. Fujishige (42). These authors studied the binary polymer systems formed by acetaldehyde, propionaldehyde, n-butyraldehyde, iso-butyraldehyde and w-heptanal. All the copolymers are crystalline over the whole range of compositions. In the case of binary copolymers of acetaldehyde, propionaldehyde and K-butyraldehyde the unit cells have the same tetragonal space group UJa, with the same chain axis (4.8 A), while the dimensions of the a axis change continuously as a function of the copolymer composition. In the case of copolymers of isobutyraldehyde with other aldehydes, the continuous variation of the lattice constants a and c were observed. 

Other aliphatic aldehydes have been identified and quantitatively measured in various brandies (31, 32). These include small amounts of formaldehyde, propionaldehyde, isobutyraldehyde, isovaleraldehyde, furfural, etc. Furfural is a normal component of pot-still distillates, but its presence in continuous still brandies is negligible before aging in wood. 

SAMPLE SOLUTION (a) Don t be fooled by the fact that the common name is isobutyraldehyde. The longest continuous chain has three carbons, and so the base name is propanal. There is a methyl group at C-2 thus the compound is 2-methyl-propanal. 

A mixture of 288 g (4 mols) of isobutyraldehyde, 288 g of methanol was cooled to 10°C and 170 g (2 mols) of 36.6% formalin containing 8.5 g (3% based on isobutyraldehyde) of sodium hydroxide was added dropwise over a 55 minute period to produce alpha,alpha-dimethyl-beta-hydroxy-propionaldehyde. The mixture was stirred for an additional 2 hours at 10-15°C and then contacted with acetic acid to neutralize the catalyst. The excess isobutyraldehyde and methanol were stripped off at a kettle temperature of 50°C at 25 mm. To the residual a,a-dimethyl-beta-hydroxypropionaldehyde a mixture of 260 ml of methanol and 2 g (0.75%) sodium cyanide was added and the solution cooled to 10°C before adding 59.4 g (2.2 mols) of hydrogen cyanide dropwise over a 35 minute period to produce a,y-dihydroxy-p,p-dimethylbutyronitrile. The mixture was stirred at 10°C for one hour period and then contacted with acetic acid to neutralize the catalyst before stripping off the excess methanol to a kettle temperature of 45°C at 18 mm. The crude cyanohydrin was then hydrolysed by heating with 4 mols of concentrated hydrochloric acid at 80°C for 2 hours, then diluting with an equal volume of water and heating at 100°C for an additional 8 hours. The aqueous mixture was extracted continuously with ethylene dichloride. The solvent was... 

In continuation to our studies with molecular oxygen as the primary oxidant[8], we now report metal phthalocynanine catalyzed oxidation of sulphides to sulphones and olefins to epoxides by dioxygen-isobutyraldehyde system under ambient conditions (Scheme-1). 

N-Phenyl-S-chloroisothiocarbamoyl diloride added drop wise during 2 hrs. at 25-30° with water-cooling to a stirred soln. of isobutyraldehyde in dry ether, stirring continued 2 hrs., the crude dry intermediate (Y 96.5%) warmed to 50° until vigorous HCl-evolution starts, and the resolidified mixture stored in vacuo over solid KOH 4-chloro-2-oxo-5,5-dimethyl-3-phenylthiazolidine (Y 81%). F. e. and reactions of the products s. G. Ottmann, G. H. Hofmann, and H. Hooks, Jr., Synthesis 1969, 136. 

The recent work of Laddha and Smith (51), who used a technique developed by Colburn and Welsh (19), is most illuminating since it presents data on the individual phase resistances. In this procedure two pure liquids of limited solubility are contacted in the absence of a third solute, and the approach to saturation of each phase can be calculated in terms of the individual resistances. The operation is analogous to contacting a pure gaswithapure liquid instudies, whereby gas-film resistances alone are obtained. Laddha and Smith used isobutyraldehyde and 3-pen-tanol Avith water in a 2-in.-diameter tower and were able to obtain data for all but the pure aldehyde film. The dispersed-phase coefficients are shown in Fig. 10.25 as a function of dispersed-phase rate. In two of the cases, where the continuous-phase rate was relatively low, the coefficients appear to depend upon dispersed phase rate only. In the third, the influence of higher continuous-phase rates on dispersed-phase hold-up and interfacial... 

To a stirred solution of HN3 in chloroform (40 mL, 7.3%, 68 mmol) at 0 °C was added freshly distilled isobutyraldehyde (4.33 g, 60 mmol). To the mixture was added dropwise cyclohexylisocyanide (5.45 g, 50 mmol) with continued ice-cooling. The mixture was then kept below 20 °C for the next three days at which point the solid was collected and then recrystallized from cyclohexane to give tetrazole 75 (9.54 g, 85%). 

An aq. soln. of glycine, ca. 0.05 mole of cupric sulfate, and 4 moles of Na-carbonate treated with ca. 8 moles of isobutyraldehyde, refluxed 30 hrs. with efficient stirring, more aldehyde added, and refluxing continued ca. 0.5 hr. until most of the blue color of the cupric ions is discharged -hydroxy-leucine. Y 67%. F. e. s. T. T. Otani and M. Winitz, Arch. Biochem. Biophys. 102, 464 (1963) with the amino acid Gu-chelate and KOH cf. H. Mix and F.-W.Wilcke, H. 337, 40 (1964). 

General procedure for Evans titanium aldol reactions (e.g., 14 41) TiCE (1.1 equiv) is added dropwise to a 0.2-M solution of 1.0 equivalent of the imide in CH2CI2 at —78 C under N2, giving a yellow slurry. After 2 minutes, 1.2 equivalents of EtN(/-Pr)2 is added dropwise, and the resulting deep red solution is stirred at —78 C under N2 for 1.5 hours. After the dropwise addition of isobutyraldehyde (1.2 equiv), stirring is continued at —78 C for 1.5 hours. The reaction is terminated by addition of 1 1 v/v of saturated aqueous NH4CI, the mixture is warmed to ambient temperature, and the product is isolated by a conventional extraction. 

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