Accession Number : ADA254708
Title : Synthetic and Mechanistic Studies on Zinc Tetrabenzporphyrins.
Descriptive Note : Final rept. May 91-Aug 91,
Corporate Author : ARMY NATICK RESEARCH DEVELOPMENT AND ENGINEERING CENTER MA
Personal Author(s) : Cullen, John W ; Remy, David E
Report Date : Aug 1992
Pagination or Media Count : 19
Abstract : Tetrabenzporphyrins have been reported to possess very high values for third-order nonlinear optical susceptibility (Chi-3). The preparation of meso substituted zinc tetrabenzporphyrins (TBP's) from isoindole, zinc acetate and aldehydes is described. The scope of the reaction is discussed with regard to several aromatic aldehydes used for the synthesis. Benzaldehydes with electron withdrawing gave little or no product, and sterically hindered aldehydes gave low yields of TBP's that were only partially substituted in the positions. Poor yields in these cases are discussed in terms of charge transfer interactions or steric factors in the reactions. A mechanism for the formation of TBP's under these conditions is presented and discussed. The mechanism involved initial condensation of isoindole and the aldehyde to form an isoindolidene which then oligimerizes and cyclizes. Then oxidation to form the fully conjugated TBP. In the oxidation, the aldehyde is proposed to function as a hydride acceptor. Plans for future research in this area are discussed. Tetrabenzporphyrins, Porphyrins, Metalloporphyrins, Nonlinear Optical Materials, Oxidation, Eye Protection.
Descriptors : *HYDRIDES , *SYNTHESIS , *CHARGE TRANSFER , *ZINC , *PROTECTION , *EYE , OPTICAL MATERIALS , CONDENSATION , PORPHYRINS , BENZALDEHYDES , ALDEHYDES , ELECTRONS , OXIDATION , ACETATES , TRANSFER , LIGHT TRANSMISSION
Subject Categories : Biochemistry
Laminates and Composite Materials
Distribution Statement : APPROVED FOR PUBLIC RELEASE