Metal - Free Multiple Carbon - Carbon and Carbon - Hydrogen Bond Activations Via Charge-Switching Mechanism in Unstrained Diindolylmethanes
Vellekkatt Jamsheena, Chikkagundagal K. Mahesha, M. Nibin Joy, and Ravi S. Lankalapalli*
A phenyliodine (III) diacetate (PIDA) mediated umpolung reactivity of the tertiary amines with suitably sub-stituted ortho-hydroxybenzyl and phenyl groups is exploited to facilitate ortho-C(sp2)-H functionalization to afford diaryl ethers. The presence of an ortho-CHO and secondary amine functionalities in the resulting diaryl ether, generated in situ, were utilized for synthesis of dibenzoxazepines and dibenzoxazepinones. Mild conditions and relative broad substrate scope, and potential for further diversification of the diaryl ethers are highlights of this methodology.
Organic Letters, 2017, 19, 6614–6617.