Angewandte
Communications
Chemie
The ATH of 1k and 1l needed EtOAc as a cosolvent to
In conclusion, we have presented a new, efficient, and
achieve the maximum diastereo- and enantioselectivities, and
the latter required a higher catalyst loading (S/C = 500) for
complete conversion (for a comprehensive study see the
Supporting Information). Here as well, the five-membered
benzofused cyclic ketones (1i–n) outperformed their six-
membered cyclic higher homologues (1o–t). And for the 4-
chromanone-derived substrate 1r, minimizing the side-prod-
uct formation necessitated the use of S/C = 100.
practical ansa-RuII-catalyzed enantio- and diastereoselective
ATH to the carbinols 2 and 3. The latter are formed by an
unprecedented double ATH/DKR in the case of CF3C(O)-
substituted benzofused cyclic ketones. The present method-
ology definitely expands and enriches the area of fluorine
research, and the generated compounds, having excellent
enantiopurity, may be further elaborated to increase molec-
ular complexity.
Moreover, access to the complementary syn diols syn-3
was demonstrated on two representative cases starting from
the stereopure monoalcohols 2 and resorting to the antipode
ent-D for the ATH of the aroyl function (Scheme 3). Thus, the
Acknowledgments
This work was supported by the Slovenian Research Agency
(grant P1-0242), and by the French-Slovenian research
collaboration Proteus. We are also grateful to Dr. Michel
Stephan from PhosPhoenix SARL, France, for very helpful
discussions and for providing ruthenium catalysts.
Keywords: alcohols · asymmetric catalysis · enantioselectivity ·
kinetic resolution · ruthenium
How to cite: Angew. Chem. Int. Ed. 2016, 55, 5294–5298
Angew. Chem. 2016, 128, 5380–5384
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96.5:3:0.5:0; > 99.9% ee) and (1R,2R,1’S)-3i (d.r. =
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Angew. Chem. Int. Ed. 2016, 55, 5294 –5298
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