Unsaturated Fatty Alcohol Derivatives as a Source of Substituted Allylzirconocene

Abstract

From A to Z: Allylzirconocenes have been easily prepared in a one‐pot procedure through a tandem allylic CH activation–β‐elimination reaction from unsaturated fatty alcohol and ether starting materials (see scheme). The reaction proceeds rapidly under mild condition and is insensitive to the length of the carbon tether between the double bond and the alcohol moiety.

Chain Walking of Allylrhodium Species Towards Esters During Rhodium‐Catalyzed Nucleophilic Allylations of Imines

“…The migration of metal centers along carbon chains occurs in several important reactions. [1][2][3][4][5][6][7] Many of these migrations take place by b-hydride elimination and hydrometalation sequences,i nw hich the direction of travel is controlled by thermodynamics,aligand, or an earby functional group. With few exceptions, [4b-f] these migrations involve simple alkylmetal species.The ability to chain walk ametal together with as econd functional group has significant synthetic opportunities,b ut this mode of reactivity remains largely underdeveloped.…”

Metal‐Catalyzed Remote Functionalization of ω‐Ene Unsaturated Ethers: Towards Functionalized Vinyl Species

“…Among several possibilities to address this issue, the ability of a transition‐metal complex to undergo a rapid “metal‐walk” along a hydrocarbon chain to functionalize the terminus position has proven to be a valuable strategy to build molecular complexity (Scheme b) . In this context, we reported the zirconocene‐mediated transformation of unsaturated fatty‐acid alcohol derivatives ( 1 ), through successive allylic C−H bond activations followed by an irreversible β‐alkoxide elimination reaction, into substituted allylzirconocene species ( 2 ; Scheme c) . We then extended this concept to the selective preparation of stereodefined dienylzirconocene species ( 4 ) from ω‐ene enol ether derivatives ( 3 ), and to the acyclic bifunctionalized products 6 through a combined zirconium chain walk and selective ring opening of ω‐ene cyclopropanes ( 5 ) .…”

A Zirconium Promenade - An Efficient Tool in Organic Synthesis

“…2) lead to the corresponding allylzirconocene derivatives in good isolated yields after hydrolysis (Scheme 8). 18 The stereochemistry of the initial double bond has no effect on the isomerization-elimination processes, since Z-or E-double bonds can be used indifferently (compare eq. 2 and eq.…”