1-Halo-cis-3-tetradecenes and processes for the preparation of cis-Olefin compounds by using same

A process for the preparation of cis-olefin compounds which comprises converting a compound having the formula

• CH.sub.3 (CH.sub.2).sub.9 CH.dbd.CH(CH.sub.2).sub.2 X.sup.a(I)
• wherein X.sup.a is selected from the group consisting of chlorine, bromine, and iodine, into an organometallic compound of the formula (II)
• CH.sub.3 (CH.sub.2).sub.9 CH.dbd.CH(CH.sub.2).sub.2 M.sup.a(II)
• wherein M.sup.a is a metal atom or MgX.sup.a in which X.sup.a is a halogen atom, and reacting the organometallic compound with a compound of the general formula RY wherein R is an alkyl group and Y is a bromine atom, iodine atom, tosyloxy group or mesyloxy group, to form a cis-olefin compound of the formula
• CH.sub.2 (CH.sub.2).sub.9 CH.dbd.CH(CH.sub.2).sub.2 R (III)
• wherein R is as previously defined.