full conversion was reached (ESI). Nevertheless, these results
show that the extremely high selectivity of CALB towards
1
-phenyl-ethanol moiety is retained on the periphery of den-
drimers. Furthermore, the chiral code of the dendrimer periph-
ery directly correlates to a chemical reaction yield using an
enantioselective catalyst. We envisage that this concept can be
employed to program reactivity into otherwise indistinguishable
molecules.
The Dutch Polymer Institute (DPI #684) and Netherlands
Organisation for Scientific Research (NWO 700.57.016) are
gratefully acknowledged for financial support. AH is a Science
Foundation Ireland Stokes Senior Lecturer (07/SK/B1241).
Financial support from the NSF (CHE-0957492) and the
MRSEC Program DMR-0520415 (MRL-UCSB) is greatly
acknowledged.
Fig. 2 Specific optical rotation of dendrimers functionalised with
different ratios of 2R : 2S.
1
2
THF in the presence of vinyl acetate. A control experiment
confirmed that under these conditions CALB cannot hydrolyse
the dendrimer. The extent of the esterification of the secondary
alcohol groups as a function of chiral composition was quanti-
Notes and references
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˜
(
˜
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872 Chem. Commun., 2011, 47, 9870–9872
This journal is c The Royal Society of Chemistry 2011