On November 16, 2017, Mpampos, Konstantin; Andersson, Thomas published a patent.Application In Synthesis of 2-Methyl-2-propylpropane-1,3-diol The title of the patent was Process for the production of a mixture of 2,2-dialkyl-1,3-propanediols by aldol reaction and subsequent crossed Cannizzaro reaction of formaldehyde with 2-methylpropanal and at least one other 2-alkylalkanal. And the patent contained the following:
The invention is related to a process for the production of mixed 2,2-dialkyl-1,3-propanediols by aldol reaction and subsequent crossed Cannizzaro reaction characterized in, that formaldehyde in presence of a strong base is subjected to aldol reaction and subsequent Cannizzaro reaction with 2-methylpropanal and at least one other 2-alkylalkanal at a molar ratio formaldehyde to 2-methylpropanal and the at least one other 2-alkylalkanal of 2-2.2:1, that 2-methylpropanal and the at least one other 2-alkylalkanal are present in a weight ratio of between 1:99 and 99:1, such as between 60:40 and 95:5, and that the process yields a mixture of 2,2-dimethyl-l,3- propanediol and at least one other 2,2-dialkyl-1,3-propanediol. The invention provides the major advantage of obtaining a ready for use diol mixture in high yield in a single reactor/production plan in the absence of any cross-aldol coupling of the substrate aldehydes, allowing the mixture to be supplied as such thus reducing the number of compounds necessary to store and/or ship by the producer and/or end user and reducing the number of and investments in reactors/production plants. For example, a reactor was charged with the specified amount of water, formaldehyde and 2-ethylhexanal and the mixture was under stirring adjusted 20° over a period of 10 min, after the 10 min, charging of sodium hydroxide commenced followed by charging of the 2-methylpropanal with a minute delay, the total charging time was 30 min, the temperature was set to increase from 20° to 30° during the same period, the temperature was after completed charging of reactants increased to 60° over a period of 15 min followed by stirring at the temperature for a further 30 min, the resulting reaction mixture was, after completed reaction, cooled to < 30° and pH was adjusted by addition of formic acid, the reaction mixture was then recovered, purified and analyzed. Following the above procedure a reaction solution containing 11.2 parts by weight of 2-ethylhexanal, 96.2 parts by weight of 2-methylpropanal, 187.6 parts by weight of 48% aqueous formaldehyde, 125.2 parts by weight of 50% aqueous sodium hydroxide and 670.0 parts by weight of water was subjected to aldol reaction and subsequent Cannizzaro reaction. 1084.5 parts by weight of a reaction mixture were, after completed reactions, isolated and the pH was adjusted to 5.5 by addition of 11.2 parts by weight of formic acid, the synthesis resulted, after recovery and purification, in a 2,2-dimethyl-1,3- propanediol yield of 97.2% and a 2-butyl-2-ethyl-1,3-propanediol yield of 96.6%, the amount of unreacted aldehydes was determined to be < 0.1% of 2-methylpropanal, < 0.1% of 2-ethylhexanal and 1.4% of formaldehyde. The experimental process involved the reaction of 2-Methyl-2-propylpropane-1,3-diol(cas: 78-26-2).Application In Synthesis of 2-Methyl-2-propylpropane-1,3-diol
The Article related to dialkylpropanediol production methylpropanal alkylpropanal aldol addition cannizzaro reaction, dimethylpropanediol butylethylpropanediol preparation methylpropanal ethylhexanal formaldehyde sodium hydroxide and other aspects.Application In Synthesis of 2-Methyl-2-propylpropane-1,3-diol
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