Subphthalocyanine encapsulated within MIL-101(Cr)-NH2 as a solar light photoredox catalyst for dehalogenation of α-haloacetophenones

Abstract

Subphthalocyanine has been incorporated into a robust metal–organic framework having amino groups as binding sites. The resulting SubPc@MIL-101(Cr)-NH₂ composite has a loading of 2 wt%. Adsorption of subphthalocyanine does not deteriorate host crystallinity, but decreases the surface area and porosity of MIL-101(Cr)-NH₂. The resulting SubPc@MIL-101(Cr)-NH₂ composite exhibits a 575 nm absorption band responsible for the observed photoredox catalytic activity under simulated sunlight irradiation for hydrogenative dehalogenation of α-haloacetophenones and for the coupling of α-bromoacetophenone and styrene. The material undergoes a slight deactivation upon reuse. In comparison to the case of phthalocyanines the present study is one of the few cases showing the use of subphthalocyanine as a photoredox catalyst, with its activity derived from site isolation within the MOF cavities.