Cyclophanes pyrenophanes

Systematic analysis of stabilities of cyclic dimeric pseudorotaxanes, generated from complementary homoditopic molecules, has been shown<99ACIE143, 99CC789> A new class of water-soluble cyclophanes, pyrenophane, capable of encompassing a neutral cavity has been constructed<99JA14S2>. 

Polycyclic aromatic hydrocarbons can be bent by bridging in a similar fashion. Two recent examples of such [n]cyclophanes are azulenophane 116 [77] and 1,8-dioxa[8](2,7)pyrenophane 117 [78]. X-ray structure analysis revealed an angle of 3.7° between the azulene ring planes, whereas the pyrene moiety is bent by nearly 90°. 

The [2.2](2,7)pyrenophane (450) has been formed in six stages from 5,3-dimethyl[2.2]metacyclophane, and the hexaoxa[6.6.6](l,3,5)cyclophane (451) made in the same number of steps from phloroglucinol... 

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