Iodomethylzinc iodide is the active reagent in the

Simmons–Smith reaction The Simmons–Smith reaction is an organic reaction, organic cheletropic reaction involving an organozinc compound, organozinc carbenoid that reacts with an alkene (or alkyne) to form a cyclopropane. It is named after Howard Ensign Simmons, Jr. an ...

. For example, iodomethylzinc iodide, formed ''in situ'' from

diiodomethane Diiodomethane or methylene iodide, commonly abbreviated "MI", is an organoiodine compound. Diiodomethane is a colorless liquid; however, it decomposes upon exposure to light liberating iodine, which colours samples brownish. It is slightly solub ...

and a zinc-copper couple reacts with

cyclohexene Cyclohexene is a hydrocarbon with the formula C6H10. This cycloalkene is a colorless liquid with a sharp smell. It is an intermediate in various industrial processes. Cyclohexene is not very stable upon long term storage with exposure to light a ...

to give

norcarane Norcarane, or bicyclo .1.0eptane, is a colorless liquid. It is an organic compound prepared using the Simmons–Smith reaction, by the action of diiodomethane and a zinc-copper couple on cyclohexene in diethyl ether Diethyl ether, or simply et ...

(bicyclo .1.0eptane). : Iodomethylzinc iodide may also be generated by the reaction of

diazomethane Diazomethane is the chemical compound CH2N2, discovered by German chemist Hans von Pechmann in 1894. It is the simplest diazo compound. In the pure form at room temperature, it is an extremely sensitive explosive yellow gas; thus, it is almost ...

with

zinc iodide Zinc iodide is the inorganic compound with the formula ZnI2. It exists both in anhydrous form and as a dihydrate. Both are white and readily absorb water from the atmosphere. It has no major application. Preparation It can be prepared by the dir ...

, or by the reaction of

methylene iodide Diiodomethane or methylene iodide, commonly abbreviated "MI", is an organoiodine compound. Diiodomethane is a colorless liquid; however, it decomposes upon exposure to light liberating iodine, which colours samples brownish. It is slightly solu ...

with

diethylzinc Diethylzinc (C2H5)2Zn, or DEZ, is a highly pyrophoric and reactive organozinc compound consisting of a zinc center bound to two ethyl groups. This colourless liquid is an important reagent in organic chemistry. It is available commercially as a ...

References

{{Zinc compounds Iodo complexes Organozinc compounds