title: Dialkyl Phosphite-Initiated Cyclopropanation of α,β-Unsaturated Ketones Using α-Ketoesters or Isatin Derivatives.
abstract: Efficient cyclopropanation of α,β-unsaturated ketones using α-ketoesters or isatin derivatives is reported. The cyclopropanation reaction occurs via a cascade transformation that starts with addition of deprotonated dialkyl phosphite to the keto groups of α-ketoesters or isatin derivatives, followed by [1,2]-phosphonate/phosphate rearrangement to generate α-phosphonyloxyenolate intermediates, which are trapped by α,β-unsaturated ketones via Michael addition/ring closure. This protocol was used to synthesize tetra-substituted cyclopropanes with a 1,2-cis-1,3-trans configuration in high yield with excellent diastereoselectivity.
authors.affiliation: Key Laboratory of Plant Resources and Chemistry of Arid Zones, Xinjiang Technical Institute of Physics & Chemistry, Chinese Academy of Sciences , Urumqi 830011, China.|University of Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Deng
authors.initials: D
authors.lastname: Yin
authors.affiliation: Key Laboratory of Plant Resources and Chemistry of Arid Zones, Xinjiang Technical Institute of Physics & Chemistry, Chinese Academy of Sciences , Urumqi 830011, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.affiliation: Key Laboratory of Plant Resources and Chemistry of Arid Zones, Xinjiang Technical Institute of Physics & Chemistry, Chinese Academy of Sciences , Urumqi 830011, China.
authors.forename: Chong-Dao
authors.identifier: 0000-0001-8968-0134
authors.initials: CD
authors.lastname: Lu
authors.affiliation: Key Laboratory of Plant Resources and Chemistry of Arid Zones, Xinjiang Technical Institute of Physics & Chemistry, Chinese Academy of Sciences , Urumqi 830011, China.
authors.forename: Yan-Jun
authors.initials: YJ
authors.lastname: Xu