Tuning the structure and the properties of dithiafulvene metalla-assembled tweezers

A M2L2 metalla-macrocycle constructed through coordination driven self-assembly from the Pd(dppf)OTf2 complex (dppf = 1,1′-bis(diphenylphosphino)ferrocene) and an electron-rich 9-(1,3-dithiol-2-ylidene)fluorene bis-pyridyl ligand is depicted. This molecular tweezer exhibits a cavity able (i) to promote dimerization upon oxidation and (ii) to bind an electro-deficient substrate with a high association constant. Those properties are compared with those of a previously described regioisomer.