32581-75-2Relevant academic research and scientific papers
Selective Mono- and Polymethylene Homologations of Copper Reagents Using (Iodomethyl)zinc Iodide
Sidduri, AchyuthaRao,Rozema, Michael J.,Knochel, Paul
, p. 2694 - 2713 (2007/10/02)
A wide range of unsaturated aryl-, alkenyl-, alkynylcopper compounds can be selectively homologated by a methylene unit using (iodomethyl)zinc iodide or bis(iodomethyl)zinc.These reactions allow the generation of mixed allylic zinc-copper compounds which can be efficiently trapped with carbonyl compounds.An application to a general preparation of functionalized α-methylene-γ-butyrolactones is described.The homologation of alkynylcoppers with (iodomethyl)zinc iodide allows a one-pot preparation of propargylic copper reagents which in the presence of a carbonyl compound provide various homopropargylic alcohols in excellent yields.In the absence of an electrophile, a clean quadruple methylene homologation of alkynylcoppers occurs to furnish dienic copper reagents.The homologation of other types of copper reagents is also possible, and carbanions at the α-position to amines as well as homoenolates of aldehydes or ketones can also be prepared by this method.
