Dimerization of 1-decene

The hydrogenated dimer of 1-decene [1208] can be used instead of conventional organic-based fluids, as can n-l-octene [1105]. 

J. D. Mercer and L. L. Nesbit. Oil-base drilhng fluid comprising branched chain paraffins such as the dimer of 1-decene. Patent US 5096883,1992. 

A mechanism for the origin of skeletal isomers observed in the cationic dimerization of 1-decene is proposed to involve a protonated cyclopropyl intermediate formed directly by reaction of a 2-decyl carbocation with 1-decene. This intermediate is said not to occur via ring closure of a branched secondary carbocation. Rapid repeated isomeriza-tions of the protonated cyclopropyl intermediates lead to a multitude of skeletal isomers (Scheme 77). ... 

---