Communications
The Diels–Alder reactivity of “calixarene-like” metal
complexes supported by the ligands H2L1 and H2L2 has been
described. The reaction between the coordinated sorbinate
coligand and acrylonitrile is controlled by the binding cavity
of the complexes and is highly regioselective. The new
method is currently only applicable to dienes with anchoring
carboxylate groups, but expansion of this approach to a
general concept for the control of the regioselectivity of
Diels–Alder reactions between unsymmetrical dienes and
dienophiles appears to be in reach. We are currently probing
the possibility whether the rate of these transformations can
be enhanced by enlarging the binding pocket of the com-
plexes.
Received: February 23, 2005
Revised: October 4, 2005
Published online: November 22, 2005
Keywords: binuclear complexes · calixarenes ·
.
Diels–Alder reaction · regioselectivity · synthetic methods
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