36528-28-6Relevant articles and documents
Investigations of cylindrical reaction cavities from ordered phases of alkyl alkanoates and their influence on some Norrish-Yang and photo-fries reactions
Baldvins, Jon E.,Cui, Changxing,Weiss, Richard G.
, p. 726 - 734 (2007/10/03)
The Norrish-Yang photochemistry of three isomeric p-alkyl alkanophenones (p-propyl nonadecanophenone, p-pentyl heptadecanophenone and p-octyl tetradecanophenone) and the photo-Fries reactions of 2-naphthyl myristate have been investigated in the ordered (layered) phases of three isomeric alkyl alkanoates. Comparisons of photoproduct selectivity for irradiation of one substrate in the isotropic and ordered phases of one host ester provide information concerning the influence of the cylindrically shaped reaction cavities on the relative motions and conformational changes necessary to convert the reactants to products. Comparisons of photoproduct distributions from one substrate in comparable phases of two or more esters provide details concerning the "wall stiffness" and importance of functional group interactions of the reaction cavities. Finally, comparisons using one substrate and two ordered phases of the same ester indicate the role of wall stiffness on photoproduct selectivity. The results show that the course of the photochemical reactions can be controlled effectively within the ordered media and provide an indication of how to design and select ordered media to effect other photochemical transformations selectively.
Fat Hydrolysis and Esterification by a Lipase from Humicola lanuginosa
Omar, Ibrahim Che,Nishio, Naomichi,Nagai, Shiro
, p. 2153 - 2160 (2007/10/02)
The hydrolysis and esterification by a thermostable lipase from Humicola lanuginosa No. 3 were investigated.Both reactions occurred readily at temperatures between 45-50 deg C.Esterification by the enzyme with glycerol was observed to be specific towards fatty acids with carbon numbers of C12-C18.Lauric acid esters with different alcohols such as primary alcohols, terpene alcohols, etc., were also synthesized readily.Esterification by the enzyme was adversely affected by the water content (optimum, ca. 7percent), however, the hydrolysis rate increased rapidly with increasing water content (optimum, ca. 60percent).The enzyme showed increased activity in organic solvent-aqueous reaction systems.Nevertheless, hydrolysis in complete organic phase reactions was found not to be feasible.Hydrolysis at a higher temperature (50 or 55 deg C) in a solvent free phase was almost the same as that in organic solvent-aqueous phase reactions.The components of glycerides varied considerably during hydrolysis, whereby esterification resulted in a higher quantity of mono- and diglycerides (about 40percent), compared to in the case of hydrolysis, for which the value was about 10-20percent.
