Cross-metathesis of Methyl Oleate and cis-2-Butene-1,4-diol: A Direct Route to Bifunctional Polymer Building Block

Abstract The cross-metathesis of methyl oleate with cis-2-butene-1,4-diol was investigated as a direct route to bifunctional polymer building blocks. In contrast to most previous cross-metathesis approaches that rely on activated terminal olefins such as acrylonitrile, the use of an unprotected internal diol as the olefin partner is less explored. In this study, the unprotected diol enables direct access to highly functionalized intermediates without protecting-group manipulations, suppresses dimer formation typically associated with terminal olefins, and allows subsequent isomerization in a single operation. Efficient cross-metathesis was achieved at low temperature (0 °C) using a Stewart–Grubbs catalyst, affording the corresponding bifunctional cross-metathesis products in high yield. The resulting intermediates were readily transformed into alcohols, aldehydes, and olefins in single-step or tandem processes, each in excellent yield (>90%). These compounds represent useful intermediates for the polymer precursor synthesis and may be further elaborated toward building blocks that have been employed in polyamide-11 monomer preparation. A tandem cross-metathesis/isomerization sequence is also demonstrated, highlighting the synthetic utility of this approach.