Photochemistry of 2‑Nitroarenes: 2‑Nitrophenyl-α-trifluoromethyl Carbinols as Synthons for Fluoroorganics

Facile
synthesis of a new series of 2,2′-bis­(trifluoroacetyl)
azoxybenzene derivatives and trifluoromethylated benzo­[c]­isoxazoline systems, along with trifluoroacetyl nitrosobenzene derivatives
was achieved by solvent controlled photolysis of appropriate 2-nitrobenzyl
alcohols. Corresponding photoactive 2-nitrobenzyl chromophore plays
a distinct role in this photosynthetic process, while, quite unprecedented,
pertinent fluoromethyl substitution leads to high value fluoromethylated
products, whose direct access is not feasible by common synthetic
protocols. The significance of fluorine and fluoroalkyl substitution
and its prominent biological effects makes this new photochemical
approach an important discovery in synthetic methodology. Plausible
mechanistic pathways involved in the formation of the products during
steady-state photolysis are further established by picosecond laser
flash photolysis experiments.