Broad Functionalization of Deep-Cavity Cavitands by Directed ortho Metalation

Abstract The endo- and exo-rim positions of deep-cavity cavitand 1 were functionalized by directed ortho metalation (DoM) procedures. A range of electrophilic quenchers led to hosts with ester, phenol and thioether functionality. In each case, a combination of host pre-organization and reaction control resulted in far fewer products than the theoretical sixty-nine. In addition to the nature of the lithiate, functionalization patterns were also dependent on the electrophile, with a general trend that the non-carbon electrophiles examined gave higher degrees of substitution. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)