Molecularly Defined Lubricant Hydrocarbons from Olefin Metathesis

Abstract

Hydrocarbon-based lubricants are ubiquitous in industrial applications but typically consist of complex mixtures of branched molecules that are challenging to characterize and to relate to their macroscopic properties. Consequently, lubricants are typically optimized empirically for specific applications by blending base oils with organic or inorganic additives. In this study, we report the synthesis and characterization of molecularly defined lubricants via metathesis of branched terminal olefins, followed by hydrogenation. The resulting saturated hydrocarbons are characterized by ultrahigh-field (28.2 T) ¹H and ¹³C NMR spectroscopies to establish their molecular structures and resolve different stereoisomers, showing the utility of state-of-the-art spectroscopic tools for analyzing structures of branched alkanes. Furthermore, the molecular-level diffusion and bulk viscosity properties compare favorably to classical synthetic lubricants based on hydrogenated polyalphaolefin (PAO) blends, establishing olefin metathesis as a selective and scalable route to high-performance lubricant oils with defined molecular structures.