J. Cossy et al. / Tetrahedron Letters 43 (2002) 7083–7086
7085
Table 2.
the attack of diisopropylamine led to 19 in 88% yield
Table 1, entries 9 and 10). Interestingly, when epoxide
was treated with hexamethyldisilazane (HMDS), the
amino alcohol 20, in which the secondary hydroxy
group was protected as a silyl ether, was isolated in
Acknowledgements
(
1
C.H. thanks the CNRS and Rhodia for a grant.
74% yield (Table 1, entry 11).
References
1
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2
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2
13
the corresponding amino alcohols 22–24 (Table 1,
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any solvent and, under these conditions, the amino
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entries 2 and 7).
2
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7
3
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reaction was performed without any solvent (Table 2,
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1
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In summary, we have discovered a novel, mild and
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4
15,16
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solvent in excellent yield. Furthermore, when LiNTf is
2
used instead of Lewis acids, the work-up is easier as no
emulsion was formed.