FULL PAPERS
Insight into the Mechanism and Stereochemistry of the Transformations
silica gel (5:1 n-hexane/EtOAc). To isolate cyclopropanols
a–h, hexane (4–5 mL) was added first to precipitate major
[10] a) Y. A. Konik, D. G. Kananovich, O. G. Kulinkovich,
manuscript in preparation; b) Y. A. Konik, D. G. Kana-
novich, O. G. Kulinkovich, unpublished results.
[11] a) E. A. Matiushenkov, N. A. Sokolov, O. G. Kulinko-
vich, Synlett 2004, 77–80; b) D. H. Churykau, V. G. Zi-
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2008, 64, 1536–1538.
6
part of TADDOL from the reaction mixture, and then crys-
tals of TADDOL were collected by filtration and washed
with hexane. The residue, after evaporation of the solvent,
was chromatographed on silica gel (hexane/EtOAc or ben-
zene/EtOAc) to give cyclopropanols cis-6a–h as colorless
liquids.
[
13] See, for example: a) T. J. Boyle, D. L. Banes, J. A. Hep-
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1, 1112–1126; b) P. J. Walsh, Acc. Chem. Res. 2003, 36,
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Acknowledgements
nometallics 2004, 23, 127–134; d) K.-H. Wu, Y.-Y. Kuo,
C.-A. Chen, Y.-L. Huang, H.-M. Gau, Adv. Synth.
Catal. 2013, 355, 1001–1008.
Support from the Ministry of Education and Research of Es-
tonia (Grant No SF0140060s12), the EU Regional Develop-
ment Fund (3.2.0101.08–0017), and NSERC Canada (Discov-
ery Grant program) are acknowledged. One of us (O.G.K.) is
deeply grateful to the administration of Tallinn University of
Technology for the invitation and hosting of two years of re-
search (2011–2013) as a visiting professor.
[
[
14] W.-S. Sheen, H.-M. Gau, Inorg. Chim. Acta 2004, 357,
2
279–2284.
1
15] The ethyl group in EtMgBr shows in H NMR spec-
trum as a system of methyl triplet and methylene quar-
tet at d=1.61 and d=À0.12 ppm, respectively (see the
Supporting Information).
[
16] The broadening of the isopropoxide signals occurs due
to their intermolecular exchange, which is verified by
positive cross peaks in 2D NOESY spectrum (see the
Supporting Information).
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Adv. Synth. Catal. 0000, 000, 0 – 0
ꢁ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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