- Retention Indices and Enthalpies of Sorption of Esters of Neopentyl Glycol on DB-1 Stationary Phase
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Abstract: The logarithmic retention indices and the enthalpies of sorption at the average temperature of an experiment and 298.2 K are determined via gas–liquid chromatography using DB-1 stationary phase for esters of neopentyl glycol and С2–С
- Krasnykh, E. L.,Levanova, S. V.,Lukina, O. D.,Portnova, S. V.
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p. 659 - 661
(2020/04/15)
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- METHOD FOR PRODUCING DIOL HAVING CYCLIC ACETAL SKELETON
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The present invention provides a method for producing a diol having a cyclic acetal skeleton, in which the method include an acetalization reaction step of obtaining a diol having a cyclic acetal skeleton by subjecting raw material hydroxypivalaldehyde and at least pentaerythritol and/or trimethylolpropane to an acetalization reaction under an acid catalyst and the raw material hydroxypivalaldehyde can contain a prescribed amount of at least one impurity selected from the group consisting of formaldehyde, neopentyl glycol, an ester compound having a neopentyl glycol skeleton represented by formula (III), and isobutyraldehyde.
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Paragraph 0157
(2019/02/28)
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- EXTERNALLY MASKED NEOPENTYL SULFONYL ESTER CYCLIZATION RELEASE PRODRUGS OF ACAMPROSATE, COMPOSITIONS THEREOF, AND METHODS OF USE
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Masked nitrogen-substituted and oxygen-substituted neopentyl sulfonyl ester prodrugs of acamprosate, pharmaceutical compositions comprising such prodrugs, and methods of using such prodrugs and compositions thereof for treating diseases are disclosed. In particular, acamprosate prodrugs exhibiting enhanced oral bioavailability and methods of using acamprosate prodrugs to treat neurodegenerative disorders, psychotic disorders, mood disorders, anxiety disorders, somatoform disorders, movement disorders, substance abuse disorders, binge eating disorder, cortical spreading depression related disorders, tinnitus, sleeping disorders, multiple sclerosis, and pain are disclosed.
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Page/Page column 44-45
(2009/04/24)
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- Process for the production of the spiroglycol 3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane
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In the production of spiroglycol by the reaction of pentaerythritol and hydroxypivalaldehyde in water in the presence of an acid catalyst, (A) a total content of amines and amine salts in hydroxypivalaldehyde is reduced to 1.5% by weight or lower; (B) seed crystals are added to the reaction system before initiating the reaction and/or during the reaction in an amount from 1.5 to 30% by weight on the basis of the total feed amount of pentaerythritol, hydroxypivalaldehyde, water, the acid catalyst and the seed crystals, each being fed into the reaction system; (C) the pH of the reaction system is kept from 0.1 to 4.0 from initiation of the reaction to completion of the reaction; and (D) the sum of a maximum theoretical amount of spiroglycol to be synthesized from pentaerythritol and hydroxypivalaldehyde to be fed into the reaction system and an amount of spiroglycol contained in the seed crystals to be added to the reaction system is controlled within a range from 5 to 35% by weight on the basis of the total feed amount. The spiroglycol produced has an increased particle size. By washing the spiroglycol with a basic solution, the heat stability is improved.
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Page/Page column 5
(2008/06/13)
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- Stabilized hydroxypivalaldehyde
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In the method of the invention, hydroxypivalaldehyde (3-hydroxy-2,2-dimethylpropanal) and/or its dimer is stored under solid conditions containing an amount of water. By storing such solid conditions, hydroxypivalaldehyde and/or its dimer is stored for a long period of time without reducing its purity.
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Page/Page column 5
(2008/06/13)
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- Selective mixed Tishchenko reaction via substituted 1,3-dioxan-4-ols
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Monoesters of 1,3-diols can be prepared with the mixed Tishchenko reaction from β-hydroxy aldehydes and another aldehyde. These two aldehydes form a diastereomeric mixture of 1,3-dioxan-4-ol hemiacetal derivatives which can be further converted to monoesters with suitable catalysts. Limitations in the formation and esterification of this hemiacetal intermediate have been investigated in this work and the formation and stability of 1,3-dioxan-4-ols was found to be aldehyde-, temperature-, and solvent-dependent. A new method was developed for selective preparation of monoesters of 1,3-diols with this mixed Tishchenko reaction via 1,3-dioxan-4-ols without any significant side products. During the development of this method a possibility to scale up the reactions to reach a selective and economical process was one of the main targets in this work.
- Toermaekangas, Olli P.,Saarenketo, Pauli,Koskinen, Ari M. P.
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p. 125 - 131
(2013/09/06)
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