NIR Photocleavage of the Si–C Bond in Axial Si-Phthalocyanines
- 4 September 2014
- journal article
- research article
- Published by American Chemical Society (ACS) in The Journal of Physical Chemistry A
- Vol. 118 (45), 10587-10595
- https://doi.org/10.1021/jp505656e
Abstract
The use of light-triggered photolysis provides a powerful tool for unique syntheses and for applications that require remote operation such as drug delivery or molecular switches. Here, we describe the photochemistry of a recently developed alkylsilicon phthalocyanine Pc 227, which undergoes an exchange of the alkyl ligand for a ligand derived from the solvent when the axial Si–C bond is photolyzed in a solvent with low-energy visible light. In this work with methanol as the solvent, we investigate the formation of the methoxy analogue of the therapeutic drug Pc 4, (termed Pc 233) upon irradiation. Using steady-state spectroscopy and characterization of the photoproducts, the competing pathways between direct ligand exchange on the central silicon atom and delocalization of the radical produced by homolysis on the phthalocyanine ring is observed. The delocalized radical intermediate is quite long-lived. At long times this intermediate decomposes without significant formation of Pc 233. The results of this investigation provide insights into recent work utilizing Pc 227 for drug delivery applications and for future work on the use of phthalocyanines as long-wavelength phototriggers.Keywords
This publication has 29 references indexed in Scilit:
- Near Infrared Light‐Triggered Drug Generation and Release from Gold Nanoparticle Carriers for Photodynamic TherapySmall, 2014
- Silicon Based Nanocoatings on Metal Alloys and Their Role in Surface EngineeringSilicon, 2010
- Synthesis of high-purity alkylsilanesTheoretical Foundations of Chemical Engineering, 2007
- A clearer vision for in vivo imagingNature Biotechnology, 2001
- Stereochemical Control in Organic Synthesis Using Silicon-Containing CompoundsChemical Reviews, 1997
- Uses of Silicon-Containing Compounds in the Synthesis of Natural ProductsChemical Reviews, 1995
- NEW PHTHALOCYANINE PHOTOSENSITIZERS FOR PHOTODYNAMIC THERAPYPhotochemistry and Photobiology, 1993
- Fast formation of methyl radical from methylaquocobaloxime as studied by time-resolved optical and ESR techniquesThe Journal of Physical Chemistry, 1990
- Vinylsilane- and alkynylsilane-terminated cyclization reactionsChemical Reviews, 1986
- Bond dissociation energy values in silicon-containing compounds and some of their implicationsAccounts of Chemical Research, 1981