Investigations of cylindrical reaction cavities from ordered phases of alkyl alkanoates and their influence on some Norrish-Yang and photo-fries reactions

Article abstract of DOI:10.1111/j.1751-1097.1996.tb09622.x

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.