Macrocycles 2-3 are synthesized by reacting 2,4-dihydroxybenzophenone with
alpha,alpha'-dibromo-p-xylene and then 1,6-diiodohexane. Photoirradiation o
f 2 yields a new type of cyclophane 5 containing two benzo[b]furan rings vi
a intramolecular delta-hydrogen abstraction. X-Ray analysis shows that 5 ha
s a rectangular cavity of ca. 5.9 Angstrom x7.6 Angstrom. (C) 2000 Elsevier
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