In this tutorial review, we discuss how recycling and stability advantages alone are frequently not sufficient to justify the effort necessary to immobilize chiral complexes unless additional advantages are found. Nanostructured solids with well-controlled surfaces and pores may act as nanoreactors, hindering or even blocking some of the reaction channels, and hence modifying the stereochemical result of the reaction. The use of support effects to improve or change the enantioselectivity is emerging as an interesting field, whose understanding might allow, in the near future, the design of chiral ligands better adapted to this strategy.
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Structures and Properties of Axially Chiral (2E,4E,6Z,8Z)-Nona-2,4,6,8-Tetraenoate Derivatives Highly Substituted by Aryl groups.
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