Stereoselective Rhodium-Catalyzed Arylzincation of Terminal Allenes

terminal allenes - three-component reaction - arylzincation - rhodium

Significance

<P>A novel efficient rhodium-catalyzed multicomponent reaction using an arylzinc iodide, a monosubstituted allene and an electrophile (E⁺) is reported. With acetonitrile and imines or aldehydes as electrophiles the use of Barbier-type conditions furnished the best yields. The reaction is highly diastereoselective, and thus allowed the synthesis of a stereodefined skipped polyene.</P>

Comment

<P>Multicomponents allow an easy one-pot access to molecular complexity. Multicomponent reactions involving allenes have recently attracted increased attention due to their efficiency. The high stereoselectivity of this reaction makes it a very valuable tool for modern synthesis.</P><P> Review: S. Ma Chem. Rev. 2005, 105, 2829-2871.</P>