Synthesis of novel asymmetrically substituted phthalocyanines
type: CreativeWork
description: Phthalocyanines are among the more promising second generation photosensitizers for photodynamic therapy. Our research group has consistently shown that the more amphiphilic of these compounds display improved biological properties as photosensitizers for photodynamic therapy. However, synthetic approaches towards such asymmetrically substituted amphiphilic phthalocyanines are quite limited. As such, we have examined different methodologies for imparting amphiphilicity to phthalocyanine-based photosensitizers. Boron subphthalocyanines are the lower homologs of phthalocyanines and the reactivity of boron subphthalocyanines allows them to react with 1,3-diiminoisoindolines in a Kobayashi ring expansion reaction to give 3:1 asymmetrically substituted phthalocyanines. While several literature examples demonstrate that this protocol can lead to a mixture of substituted phthalocyanine products, the ring expansion reaction of halogenated boron subphthalocyanines in the current study has proven to proceed smoothly to selectively produce the desired 3:1 asymmetrically substituted products. Fluorinated photosensitizers have been previously demonstrated to have interesting properties for PDT and a series of 3:1 asymmetrically substituted dodecafluorinated phthalocyanines have been synthesized by the Kobayashi ring expansion reaction of (dodecafluorosubphthalocyaninato)boron(III) bromide. The asymmetry in these lipophilic compounds improves the photodynamic efficiency of these photosensitizers compared to previously examined symmetrically substituted fluorinated phthalocyanine derivatives. The chemical versatility of aryl iodides, in particular towards palladium-catalyzed reactions, allows for the controlled addition of novel functionality to 3:1 asymmetrically substituted iodinated phthalocyanines prepared by the Kobayashi ring expansion reaction of iodinated boron subphthalocyanines. Palladium-catalyzed reactions have thus been employed in the preparation of new amphiphilic a…
abstract: Phthalocyanines are among the more promising second generation photosensitizers for photodynamic therapy. Our research group has consistently shown that the more amphiphilic of these compounds display improved biological properties as photosensitizers for photodynamic therapy. However, synthetic approaches towards such asymmetrically substituted amphiphilic phthalocyanines are quite limited. As such, we have examined different methodologies for imparting amphiphilicity to phthalocyanine-based photosensitizers. Boron subphthalocyanines are the lower homologs of phthalocyanines and the reactivity of boron subphthalocyanines allows them to react with 1,3-diiminoisoindolines in a Kobayashi ring expansion reaction to give 3:1 asymmetrically substituted phthalocyanines. While several literature examples demonstrate that this protocol can lead to a mixture of substituted phthalocyanine products, the ring expansion reaction of halogenated boron subphthalocyanines in the current study has proven to proceed smoothly to selectively produce the desired 3:1 asymmetrically substituted products. Fluorinated photosensitizers have been previously demonstrated to have interesting properties for PDT and a series of 3:1 asymmetrically substituted dodecafluorinated phthalocyanines have been synthesized by the Kobayashi ring expansion reaction of (dodecafluorosubphthalocyaninato)boron(III) bromide. The asymmetry in these lipophilic compounds improves the photodynamic efficiency of these photosensitizers compared to previously examined symmetrically substituted fluorinated phthalocyanine derivatives. The chemical versatility of aryl iodides, in particular towards palladium-catalyzed reactions, allows for the controlled addition of novel functionality to 3:1 asymmetrically substituted iodinated phthalocyanines prepared by the Kobayashi ring expansion reaction of iodinated boron subphthalocyanines. Palladium-catalyzed reactions have thus been employed in the preparation of new amphiphilic a…
author: Sharman, Wesley Milton
language: en
date published: 2005
date modified: 2026-07-27T21:07:39Z
provider: Université de Sherbrooke
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Université de Sherbrooke

PropertyValue
property ID: Handle
value: https://hdl.handle.net/11143/4220