Allylic tin(IV)-tin(II) chloride-acetonitrile as a novel system for allylation of carbonyls or imines
作者:Makoto Yasuda、Yoshihiro Sugawa、Akihiro Yamamoto、Ikuya Shibata、Akio Baba
DOI:10.1016/0040-4039(96)01285-3
日期:1996.8
Effective allylation of aldehydes, ketones and imines was accomplished by allylic tributyltins 1 in the presence of SnCl2 in an acetonitrile solution. In this reaction system. Sn(IV)Sn(II) transmetallation must play a key role, generating the allylictin(II) reagents as a novel reacting species. Acetonitrile effectively promoted the transmetallation to give anti-adducts in the reaction with cinnamyltin
Reactions and characterization of allylic and related zirconium reagents (allenic and γ-alkoxyallylic zirconiums) generated by treatment of allylic and/or propargylic ethers with a zirconocene-butene complex (“Cp2Zr”) are described.
Diastereoselective synthesis of (Z)- and (E)-homoallylic alcohols using a Pd-catalyzed three-component reaction of 3-(pinacolatoboryl)allyl benzoates, aldehydes, and aryl stannanes was developed, which provides an alternative method for the allylboration of aldehydes using α,γ-diaryl-substituted allylboronates. Both sets of reaction conditions enable access to either (Z)- or (E)-homoallylic alcohols
Stereoselective [2,3]-Sigmatropic Rearrangements of Unstabilized Nitrogen Ylides
作者:Robert E. Gawley、Kwangyul Moon
DOI:10.1021/ol071188v
日期:2007.8.1
The steric course of the [2,3]-rearrangement of several unstabilized nitrogen ylides has been investigated. The reactions proceed cleanly through an anti transition state, affording modest to good yields of a single diastereomer of the product. In two examples containing an N-cinnamyl group, a competing [1,2]-rearrangement affords a minor product.
Pd-Catalyzed Three-Component Reaction of 3-(Pinacolatoboryl)ally Acetates, Aldehydes, and Organoboranes: A New Entry to Stereoselective Synthesis of (<i>Z</i>)-<i>anti</i>-Homoallylic Alcohols
作者:Yoshikazu Horino、Ataru Aimono、Hitoshi Abe
DOI:10.1021/acs.orglett.5b01244
日期:2015.6.5
Pd-catalyzed three-component reaction of 3-(pinacolatoboryl)allyl acetates, aldehydes, and organoboranes is described. The reaction is initiated by the formation of an allylic gem-palladium/boryl intermediate, which then undergoes allylation of aldehydes by allylboronates followed by a coupling reaction of in situ generated (Z)-vinylpalladium acetates with organoboranes to provide the (Z)-anti-homoallylic