Improvement of Lubricant Materials Using Ruthenium Isomerization

Abstract

Production of an effective industrial lubricant additive from vegetable oils is a high profile and difficult undertaking. One candidate is alkyl 9(10)-dibutylphosphonostearate, which has been made through a radical transformation of alkyl 9-cis-octadecanoate. It is effective, but still suffers from drawbacks. In this report, that synthesis is combined with a ruthenium based isomerization process to create not just one, but an entire series of new chemical compounds. A low level of [Ru(CO)₂(EtCO₂)]_n is first used for the isomerization of the starting material, then radical chemistry is employed. A series of methyl dibutylphosphonooctadecanoates was made. In an analogous fashion, trans-7-tetradecene was also isomerized and then polymerized. As in the phosphonate case, the follow-up chemistry could be performed in the presence of the residual isomerization catalyst. The alkane:alkene ratio, observed by ¹H NMR, was found to change from 14:1 in the isomerized starting material to a value of 41:1 in the polymerized material. This methodology, isomerization in tandem with other reactions, gives suitable routes to both biobased polyolefins, and biobased phosphonates, potential key ingredients in biobased lubrication formulations.

Keywords:

• Isomerization
• Octadecenoic acid
• Phosphonate
• Polyalphaolefin
• Ruthenium carbonyl carboxylate

Acknowledgments

The authors acknowledge Karl E. Vermillion for NMR spectra used in this work.