Beta-hydroxypropionaldehyde

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... 

PROBABLE FATE photolysis photooxidation m atmosphere, photooxidation half-life in air 3.4-33.7 hrs, reacts with photochemically produced hydroxyl radicals with a half-life of 0.001 hr oxidation occurs slowly hydrolysis not an important process volatilization principle transport mechanism, expected to volatilize quickly from dry soil, volatilization half-life from a model river 10 days sorption not an important process biological processes biotrans-formation occurs, biodegradation is slow at low concentrations reversible hydration to beta-hydroxypropionaldehyde, half-life 21 days... 

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. 

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