Recoverable dyes the concept of photoinitiator catalysts

A recent research direction was focused on the use of the photoredox catalysis (well-known and largely employed in organic synthesis [XIA 15, SHI 10]) in the pol5mierization area where the development of sustainable radical-mediated chemical processes under very soft irradiation conditions can be of interest (see a review in [LAL 14b]). The goal is twofold  

Metal-based Pis have been well-known for many years [CUN 93] in particular, the titanocenes for exposure to visible light sources represent a famous (and even unique) example [ROL 86]. A strong revival of interest 

Dye-based PISs as a source of mediator radicals application to FRPCP 

As known for many years [FOU 12a, XIA 15, LED 78, TEH 10b], in FRPCP ([1.16]-[1.17], [1.41]), the excited dye imdergoes the formation of a radical R that is oxidized by an iodonium salt and generates a cation suitable for the ring opening reaction of epoxides [1.45]. The originally 

Dyes exhibiting a dual radical/cationic behavior application to concomitant radical/cationic photopolymerizations 

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