Facile preparation of cyclopropanes from 2-iodoethyl-substituted olefins and 1,3-dihalopropanes with zinc powder
Daisuke Sakuma and Hideo Togo*
*Department of Chemistry, School of Science and Engineering, Waseda
University, Shinjuku, Tokyo 169-8555, Japan, Email: togofaculty.chiba-u.jp
D. Sakuma, H. Togo, Tetrahedron, 2005, 61, 10138-10145.
DOI: 10.1016/j.tet.2005.07.103
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Abstract
Efficient, simple, cheap, and environmentally benign preparations of cyclopropanes were achieved. One method is based on a 3-exo-trig cyclisation of various electron-deficient 2-iodoethyl-substituted olefins with zinc powder in a mixture of t-butyl alcohol and water, and the other on a 3-exo-tet cyclisation of various 1,3-dihalopropanes with zinc powder in ethanol.
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proposed reaction pathway
Key Words
Cyclopropanes, 3-exo-trig, 3-exo-tet, Zinc
ID: J72-Y2005-3120