Chiral dimers of a chiral pentamethine cyanine dye and of an achiral pentamethine cyanine dye in γ-cyclodextrin as chiral host

Chiral dimers are formed from the chain-substituted chiral pentamethine cyanine dye 1 at low temperatures and from the corresponding unsubstituted achiral dye 2 in γ-cyclodextrin as chiral host; the geometry of both dimers, on the basis of UV–VIS and circular dichroism (CD) spectroscopy, are quite similar corresponding, presumably, to a twisted sandwich.