Abstract:
:The aim of this work was to establish structure-reactivity relationships between chiral aggregates (micelles, vesicles, and "pseudo-micelles" of amphiphilic dendrimers) and asymmetric induction. In water, micelles or vesicles formed with sugar-headed surfactants gave less than 10% ee in the reduction of prochiral ketones by NaBH(4), in contrast with dendrimers bearing the same types of sugar moieties, which gave more than 50% ee under the same reaction conditions. Moreover, in the presence of neoglycodendrimers in THF we have been able to improve reduction of prochiral ketones to give very high stereoselectivity, near 100% in many cases. Comparison of these results suggests that to improve high stereoselectivity it is necessary to work with rigid, well-organized colloidal objects. Copyright 2000 Wiley-Liss, Inc.
journal_name
Chiralityjournal_title
Chiralityauthors
Rico-Lattes I I,Schmitzer A,Perez E,Lattes Adoi
10.1002/1520-636X(2001)13:1<24::AID-CHIR5>3.0.CO;2subject
Has Abstractpub_date
2001-01-01 00:00:00pages
24-28issue
1eissn
0899-0042issn
1520-636Xpii
10.1002/1520-636X(2001)13:1<24::AID-CHIR5>3.0.CO;2journal_volume
13pub_type
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