Synthesis and conformations of phosphine- and phosphinite-derivatized resorcinarenes

The synthesis of resorcinarene derivatives with four or eight alkynyldiphenylphosphine or diphenyl phosphinite functional groups is reported. The tetraphosphinite derivatives have effective C-2v symmetry and have the potential to adopt two different boat conformations in which the arene groups with phosphinite substituents are horizontal or vertical. A method for the determination of the solution-state conformation of the resorcinarene skeleton using correlated H-1 and C-13 NMR data is reported, and the boat conformation of one tetraphosphinite compound in the solid state has been determined crystallographically.