Self-Assembly of Rings, Catenanes, and a Doubly Braided Catenane Containing Gold(I): The Hinge-Group Effect in Diacetylide Ligands

Reaction of the flexible dialkynyldigold(I) precursors X(4‐C6H4OCH2CCAu)2 with 1,4‐bis(diphenylphosphino)butane gave complexes of formula [{[μ‐X(4‐C6H4OCH2CCAu)2][μ‐(Ph2PCH2CH2CH2CH2PPh2)]}n]. The complexes exist as 25‐membered ring compounds with n=1 when X=O or S, as [2]catenanes with n=2 when X=CH2 or CMe2, and as a unique doubly braided [2]catenane, containing interlocked 50‐membered rings with n=4 when X=cyclohexylidene. These compounds form easily and selectively by self‐assembly; reasons for the selectivity are also discussed. A unique doubly braided [2]catenane (see figure), as well as simple rings or singly braided [2]catenanes, form easily and selectively by self‐assembly on reaction of a flexible dialkynyldigold(I) precursor [X(4‐C6H4OCH2CCAu)2] with 1,4‐bis(diphenylphosphino)butane. The hinge group X determines the preferred topological isomer.