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Published on: June 21, 2017
Dimethoxyacetaldehyde-N-triftosylhydrazone: Preparation and Carbene Reactivity in Cyclopropanation and Doyle-Kirmse
Yifan Zhang1, Shuang Li2, Hongzhu Chen1
1Department of Chemistry, Northeast Normal University, Changchun 130024, PR China.
Abstract:
Herein, we developed the new, powerful, and easy-to-handle chemical reagent, dimethoxyacetaldehyde-N-triftosylhydrazone (DMHz-Tfs), as a convenient in situ source of dimethoxydiazoethane under mild conditions. We demonstrate the carbene reactivity of DMHz-Tfs in iron-catalyzed cyclopropanation and Doyle-Kirmse reactions, providing access to diverse acetal functionalized cyclopropanes and homoallylic- and allenyl-sulfides at gram-scale with high stereoselectivity. DFT calculations elucidated the involvement of the most stable doublet spin state iron-carbene intermediate over other possible spin states.
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