Three-Way Chemodivergent Derivatization of Non-Activated 2-Arylphenyl Benzyl Ethers.

A thermally controlled rare chemodivergent mechanistic trifurcation has been found through experimental and computational efforts. Notably, one of the available paths in this three-way mechanism allows for an unprecedented dearomatization reactivity of non-activated 2-arylphenyl benzyl ethers under very mild thermal conditions after Csp-H bond functionalization through α-lithiation, bringing easy access to regioselectively functionalized dearomatized benzochromene scaffolds via anionic dearomatization enabled by carbolithiation of a non-activated aromatic ring. A [1,2]-Wittig rearrangement and a benzyl migration reaction complete the available product alternatives. Moreover, a delicate but useable balance within this reaction path manifold permits steering the reactivity toward each of the three possible products. A kinetically-, thermodynamically- and quantum tunneling-controlled path can be selected to afford one of its three possible products by only tuning reaction time and temperature.