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Ministry of Education, Science, Sports, and Culture,
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. (a) Pique, C.; Fahndrich, B.; Pfaltz, A. Synlett 1995,
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1
2. Enantioselectivity of intermolecular cyclopropanation
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catalyst: (E)-3-Cinnamyl a-diazoacetate (0.1 mmol, 20.2
mg) was placed in a Schlenk tube and the tube was
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3
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. Park, S.-B.; Murata, K.; Matsumoto, H.; Nishiyama, H.
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(
25°C) and the solvent was removed in vacuo. The crude
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residue was chromatographed on silica gel using hexane
and ethyl acetate as eluent to give bicyclic lactone (13 mg)
in 75% yield. The ee of the product was determined by
GLC analysis using CHIRAL b-DEX column operated
at 160°C.
1
6
7
8
. Rh (4S-MPPIM)4 has been reported to be an efficient
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2
catalyst for intramolecular cyclopropanation of 2-alkenyl
a-diazoacetates of various substitution patterns: Doyle,
.
.