Enolate–homoenolate equivalents 1 can be prepared in one step by the title reaction. They act as functionalized Z‐γ‐siloxyallyl zinc reagents 2 by undergoing ring opening in the presence of a Lewis acid. Addition of 2 to tosylimines gives vic‐amino alcohols with high diastereoselectivity, presumably due to a fixed conformation resulting from coordination of the metal atom.

Treatment of alpha,beta-unsaturated ketones with an electrophilic site at the gamma-position in the presence of trimethylsilyl cyanide with bis(iodozincio)methane afforded the (Z)-silyl enol ether of the beta-cyclopropyl substituted ketone in good yields. The reaction proceeds by 1,4-addition to form an enolate, and its sequential intramolecular nucleophilic attack to an adjacent electrophilic site. The reaction of gamma-ethoxycarbonyl-alpha,beta-unsaturated ketone and bis(iodozincio)methane in the presence of trimethylsilyl cyanide afforded 1-ethoxy-1-trimethylsiloxycyclopropane derivatives, which can be regarded as the homoenolate equivalent. Additionally, reaction of the obtained homoenolate equivalents with imines give 1-(E)-alkenyl-2-(1-aminoalkyl)alkanols diastereoselectively.

Reactive functionalized enolates that are otherwise difficult to obtain can be prepared in a simple procedure by the treatment of a thiol ester with bis(iodozincio)methane in the presence of a palladium catalyst (see scheme). The terminal zinc enolates thus formed are kinetically controlled and react with a variety of electrophiles, such as aldehydes, ketones, and acyl cyanides. FG=functional group.

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In einem Schritt werden die Enolat‐Homoenolat‐Äquivalente 1 durch die Titelreaktion erzeugt. Durch Ringöffnung in Gegenwart einer Lewis‐Säure entstehen (Z)‐γ‐Siloxyallylzinkreagentien 2, die an Tosylimine addieren und mit hoher Diastereoselektivität vic‐Aminoalkohole liefern. Vermutliche Ursache der Selektivität ist eine durch Koordination des Metallzentrums fixierte Konformation.