Propargyl organometallic compounds

Complexes of iron and other metals which are prepared from a allyl or propargyl organometallic compounds and (NC)2C = C(CN)2, SO2, or related unsaturated electrophilic molecules via cycloaddition reactions are important because such complexes may find application in organic synthesis " ... 

The direct substitution of hydroxyl groups can also be extended towards propargylic alcohols. In the presence of FeCl3, a plethora of O-, N- or S-nudeophiles are able to react with substituted propargylic alcohols [17]. Amongst the variety of nucleophiles, allylsilanes occupy an important position since this example resembles a cross-coupling reaction between an organometallic compound and an alcohol (Scheme 7.12) [17]. 

Acetals prepared from chiral diols and carbonyl compounds serve as a chiral synthetic equivalent of aldehydes or ketones. 1,3-Dioxanes synthesized from chiral 2,4-pentanediols are especially useful, and high asymmetric inductions are observed in the Lewis acid promoted reactions of a variety of organometallic compounds. After the removal of the chiral auxiliary by the oxidation and -elimination procedures, optically active alcohols are obtained. Optically active propargylic alcohols and cyanohydrins are synthesized from organosilane compounds, TMS-C CR or TMS-CN in the presence of TiCU (Scheme 24). 1 6-138 Reactive wganometals such as alkyl-lithiums, -magnesiums or -coppers also react with chiral... 

Synthesis of heterocyclic and carbocyclic compounds via alkynyl, allyl, and propargyl organometallic cyclopentadienyl iron, molybdenium and tungsten complexes 00CRV3127. 

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