Direct Access to 4,5<i>-</i>Disubstituted [2.2]Paracyclophanes by Selective<i>ortho</i>-Halogenation with Pd-Catalyzed C-H Activation
作者:Joshua J. P. Kramer、Ceylan Yildiz、Martin Nieger、Stefan Bräse
DOI:10.1002/ejoc.201301723
日期:2014.2
A palladium-catalyzed protocol for the halogenation of [2.2]paracyclophanes by C–Hactivation is described, and ortho selectivity is achieved with an O-methyloxime directing group. Bromination and iodination of the sterically demanding [2.2]paracyclophane proceed in good yields with inexpensive and readily available N-halosuccinimides. Deprotection of the O-methyloximes yields ortho-halogenated aldehydes