Corey-House Synthesis

The Corey–House synthesis (also called the Corey–Posner, Whitesides–House reaction and other permutations) is an organic reaction that involves the reaction of a lithium dialkyl cupratewith an alkyl halide to form a new alkane, an organocopper compound and a lithium halide

                                                     R₂CuLi + R'-X → R-R' + RCu + LiX

This reaction occurs in two steps. The alkyl halide is treated with lithium metal, and solvated in ether, which converts the alkyl halide into an alkyl lithium compound, R-Li. The starting R-X can be primary, secondary or tertiary alkyl halide:

R-X + 2Li → R-Li + Li-X

The second step requires the alkyl lithium compound to be treated with cuprous iodide (CuI). This creates a lithium dialkyl cuprate compound. These compounds were first synthesized by Henry Gilman of Iowa State University, and are usually called Gilman reagents in honor of his contributions:

2RLi + CuI → R₂CuLi + LiI

The lithium dialkyl cuprate is then treated with the second alkyl halide, which couples to the compound:

R₂CuLi + R'-X → R-R' + RCu + LiX

If second alkyl halide is not the same as the first, then cross-products are formed.

It is important to note that for this reaction to work successfully, the second alkyl halide must be a methyl halide, benzyl halide, primary alkyl halide or a secondary cyclo alkyl halide. The relative simplicity of this reaction makes it a useful technique for synthesizing organic compounds.