anti-hydromagnesiation of aryl alkynes was established using 1 : 1 molar combination of sodium hydride (NaH) and magnesium iodide (MgI2) without the aid of any transition metal catalysts. The resulting alkenylmagnesium intermediates could be trapped with a series of electrophiles, thus providing facile accesses to stereochemically well-defined functionalized alkenes. Mechanistic studies by experimental
Studies on the zirconium-mediated alkyne–aldehyde coupling reactions: a facile synthesis of stereodefined allylic alcohols and (Z)-2-en-4-yn-1-ols
作者:Shenghai Guo、Hao Zhang、Feijie Song、Yuanhong Liu
DOI:10.1016/j.tet.2006.12.051
日期:2007.2
An improved zirconium-mediated alkyne–aldehyde cross-coupling reaction has been achieved to afford the stereodefined (Z)-allylic alcohols or 3-iodinated allylicalcoholsselectively via protonolysis or iodinolysis of the corresponding five-membered oxazirconacycles. This method has also been successfully applied to the synthesis of (Z)-enynols through cross-coupling reactions of three different components