Pon de relay: A convenient and efficient synthesis of alkene‐functionalized furansfromcyclopropenes, which proceeds through an isomerization/olefination cascade sequence under copper–palladium relaycatalysis, has been developed (see scheme).
Pon de relay:已经开发了一种方便有效的方法,从环丙烯中合成烯烃官能化的呋喃,该过程在铜-钯中继催化下通过异构化/烯化级联序列进行(参见方案)。
Catalytic Enantioselective Hydroboration of Cyclopropenes
作者:Marina Rubina、Michael Rubin、Vladimir Gevorgyan
DOI:10.1021/ja034210y
日期:2003.6.1
2,2-Disubstituted cyclopropyl boronates have been synthesized with high degrees of diastereo- and enantioselectivity via the rhodium-catalyzed asymmetric hydroboration of 3,3-disubstituted cyclopropenes. A strong directing effect of ester and alkoxymethyl substituents has been demonstrated. The directing effect was found to be necessary in achieving high degrees of enantiomeric induction. Selected
Simple Large-Scale Preparation of 3,3-Disubstituted Cyclopropenes: Easy Access to Stereodefined Cyclopropylmetals via Transition Metal-Catalyzed Hydrometalation
作者:Vladimir Gevorgyan、Michael Rubin
DOI:10.1055/s-2003-44368
日期:——
3-Disubstituted cyclopropenes have been readily prepared in a multigram scale via two different methods: (1) dehydrohalogenation of bromocyclopropanes, and (2) Rh-catalyzed addition of carbenoids to trimethylsilylacetylene followed by desilylation. Highly diastereoselective Pd-catalyzed hydrostannation and highly enantioselective Rh-catalyzed hydroboration of 3,3-disubstituted cyclopropenes afforded useful
Glycolates or glycinates derived from diversely substituted secondary cyclopropenylcarbinols have been involved for the first time in an Ireland–Claisenrearrangement. This reaction allows an efficient and stereoselective access to highly functionalized alkylidenecyclopropanes possessing an α-hydroxy or α-amino acid subunit, which in turn are valuable precursors of substituted cyclopropanes by diastereoselective
Synthesis of bicyclo[3.1.0]hexanes by (3 + 2) annulation of cyclopropenes with aminocyclopropanes
作者:Bastian Muriel、Alec Gagnebin、Jerome Waser
DOI:10.1039/c9sc03790j
日期:——
We report the convergent synthesis of bicyclo[3.1.0]hexanes possessing an all-carbon quaternary center via a (3 + 2) annulation of cyclopropenes with cyclopropylanilines. Using an organic or an iridium photoredox catalyst and blue LED irradiation, good yields were obtained for a broad range of cyclopropene and cyclopropylaniline derivatives. The reaction was highly diastereoselective when using difluorocyclopropenes