Guest-Reaction Driven Cage to Conjoined Twin-Cage Mitosis-Like Host Transformation

We report here a guest-reaction-induced mitosis-like host transformation from a known Pd(4)L(2)cage1to a conjoined Pd(6)L(3)twin-cage2featuring two separate cavities. The encapsulation of 1-hydroxymethyl-2-naphthol (G1), a known ortho-quinone methide (o-QMs) precursor, within the hydrophobic cavity of cage1is found crucial to realize the cage to twin-cage conversion. ConfinedG1molecules within the nanocavity undergo self-coupling dimerization reaction to form 2,2 '-dihydroxy-1,1 '-dinaphthylmethane (G2) which then triggers the cage to twin-cage mitosis. The same conversion also proceeds, in a much faster rate, via the direct templation ofG2, confirming the induced-fit transformation mechanism. The structure of the (G2)(2)subset of 2host-guest complex has been established by X-ray crystallographic study, where cis- to trans- conformational switch on one bridging ligand is revealed.