Pseudomacrocycles

Figure 3 Photoregulation of polymer-pseudomacrocycle interconversion in a 9(n = 3) + H3N+ — (CH2)6 — NH+ system the circle indicates benzo-18-crown-6.

Replacement of the interhgand hydrogen bonds in the pseudomacrocyclic complex [Pt(R,5 -L1217)2] with electrophilic boron-containing bridges affords macro-cyclic complexes pPt(R,5 -L1218)] similar to those from oxime nickel(II) complexes (Eq. 5.6) [11]. 

Switching of helicity of a Cu+ complex unit in a pseudomacrocycle 7 Cu was achieved by achiral Na binding (Scheme 1.3). Equilibrium between non-helical and helical forms effectively shifts to the helical form upon Na binding. This unique helicity control provides a new strategy for controlling helical sense because an aehi-ral guest Na regulates the chiral structures. 

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