The mechanistic details of a reported allylation reaction are investigated by means
of Stern–Volmer experiments and nanosecond transient absorption spectroscopy. Both
reference substrates, i.e., an allylic chloride and a trifluoroacetamide, are inefficient
quenchers but large quenching rate constants are observed upon the addition of Ni(COD)2 and a bisoxazoline ligand. The large quenching rate constants and absence of observable
photoproducts are consistent with a mechanism that operates by energy transfer between
the excited-state iridium photosensitizer and the nickel complex.
Key words
photoredox - energy transfer - mechanism - iridium - transient absorption - quenching
- Stern–Volmer