Long-chain Alkene Oligomerization

Oligomerization of long-chain alkenes or dienes and cycloalkene [53] yields products of higher average molecular weight that are suitable for use as lubricating oil, base oil, gasoline and jet fuel [54]. 

Applications of anionic processes [55], metathesis reactions [56-58], and cationic or radicalic procedures [60,61] to oligomerization of long-chain alkenes have been presented in the scientific literature. 

Various catalytic systems such as boron trifluoride [62,63], aluminum chloride [64-67], tantal halides [68], zirconium halides [69,70], zeolites [71-73], molecular sieves containing metallic oxides [74], ion exchangers [75], fluoroal-kane sulfonic acid [76], and montmorilonite [77] have been used to promote oligomerization of long-chain alkenes, cycloalkenes, and dienes. 

The oligomerization of olefins can form alkenes of a single length, or they can form a distribution of alkenes of various chain lengths. In the former case, dimers or trimers of olefins are the products that can typically be formed selectively. In the latter case, 1-alkenes (long-chain a-olefins) are produced that are significantly shorter than the material produced by olefin polymerization. 

As outlined earlier, this class of materials is the product of the Friedel-Crafts alkylation of benzene with a long-chain alkyl group the prime example is dodecyl-benzene. This compound may be derived from an alkyl chloride containing an average of 12 carbon atoms. The source of the alkyl chain may be a particular cut of petroleum distillate or a synthetic hydrocarbon chain obtained by the controlled oligomerization of a low-molecular-weight alkene—generally ethylene or propylene. 

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