Towards an Effective Synthesis of Difunctionalized Heptacyclo [6.6.0.0 2,6 .0 3,13 .0 4,11 .0 5,9 .0 10,14 ]tetradecane: Ligand Effects on the Cage Assembly and Selective C−H Arylation Reactions

Abstract

Abstract A series of strong π‐acceptor polyfluorinated and dicationic chelating phosphines have been synthesized and evaluated in the Rh‐catalysed dimerization of norbornadiene (NBD) into its thermodynamically more stable dimer, heptacyclo[6.6.0.02,6.03,13.04,11.05,9.010,14] tetradecane (HCTD). While dicationic ligands direct the dimerization towards HCTD, by the use of neutral polyfluorinated ancillary ligands endo‐endo‐heptacyclo [8.4.0.02,12.03,8.04,6.05,9.011,13]tetradecane (BINOR−S) is selectively obtained. In addition, a selective Pd‐catalysed arylation at position C8 of the HCTD framework is achieved by the use of a picolylamide directing group previously attached at C1. Theoretical calculations have been performed to understand the origin of that regioselectivity. image