3-Hydroxypropionaldehyde acid

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 ambient air, the primary removal mechanism for acrolein is predicted to be reaction with photochemically generated hydroxyl radicals (half-life 15-20 hours). Products of this reaction include carbon monoxide, formaldehyde, and glycolaldehyde. In the presence of nitrogen oxides, peroxynitrate and nitric acid are also formed. Small amounts of acrolein may also be removed from the atmosphere in precipitation. Insufficient data are available to predict the fate of acrolein in indoor air. In water, small amounts of acrolein may be removed by volatilization (half-life 23 hours from a model river 1 m deep), aerobic biodegradation, or reversible hydration to 0-hydroxypropionaldehyde, which subsequently biodegrades. Half-lives less than 1-3 days for small amounts of acrolein in surface water have been observed. When highly concentrated amounts of acrolein are released or spilled into water, this compound may polymerize by oxidation or hydration processes. In soil, acrolein is expected to be subject to the same removal processes as in water. 

Oxidation of aqueous solutions (10% wlw ) of 3-hydroxypropionaldehyde (HPA) in the presence of 3 % Pd/C catalysts at pH 8 produces malonic acid. Complete conversion, with 96.7 % yield, was achieved with large amounts of catalyst (33% wlw Pd relative to HPA) [91]. Starting from 3-hydroxypropionic acid the malonic acid selectivity was 95.4 % at 97 % conversion. In the presence of 5 % Pt/C catalysts (28 % wlw Pt with respect to HPA), aqueous solutions (10% wlw) of 3-hydroxypropionaldehyde were oxidized into 3-hydroxypropionic acid, an intermediate used to prepare pharmaceutical and agricultural products. The best yield, obtained without pH regulation, was 92.9% at 97.2% conversion [92]. 

Degradation and evaporation seem to be the major pathways for acrolein loss in water smaller amounts are lost through absorption and uptake by aquatic organisms and sediments. The half-time persistence of acrolein in freshwater is 38 h at pH 8.6, and 50 h at pH 6.6 degradation is more rapid when initial acrolein concentrations are less than 3000.0 pg/L. Acrolein has a half-time persistence of 2.9-11.3 h at initial nominal concentrations of 20.0 pg/L, and 27.1-27.8h at 101.0pg/L. At pH 5, acrolein reacts by reversible hydrolysis to produce an equilibrium mixture with 92% beta-hydroxypropionaldehyde and 8% acrolein in alkali, the primary reaction is consistent with a polycondensation reaction. Microbial degradation plays a major role in the ttans-formation of aaolein in aquatic systems. In natural waters, acrolein degradation proceeds to carboxylic acid via a microbial pathway beta-hydroxypropionaldehyde is readily biotransformed in about 17.4 days. 

Figure 11.7. Metabolic formation of 1,3-propanediol and 3-hydroxypropionic acid from glycerol through the Intermediate 3-hydroxypropionaldehyde (3-HPA) by some lactic acid bacteria. Acrolein is formed through a chemical dehydration of 3-HPA. Adapted from Sobolov and Smiley (1960), Sllnlnger et al. (1983), and Schiitz and Radler (1984).

Hydroxypropionaldehyde-specific aldehyde dehydrogenase from Bacillus subtilis catalyzes 3-hydroxypropionic acid production in Klebsiella pneumoniae. Biotechnd. Lett, 37 (3), 717-724. 

Sabet-Azad, R., Sardari, R.R., Linares-Pasten, J.A., and Hatti-Kaul, R. (2015) Production of 3-hydroxypropionic acid from 3-hydroxypropionaldehyde by recombinant Escherichia coli co-expressing Lactobacillus reuteri propanediol utilization enzymes. Biore-sour. TechnoL, 180, 214-221. 

Claisse, O. and Lonvaud-Funel, A. (2001) Primers and a specific DNA probe for detecting lactic acid bacteria producing 3-hydroxypropionaldehyde from glycerol in spoiled ciders. J Food Prot 64, 833-837. 

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