Promotion of Selective Pathways in Isomerizing Functionalization of Plant Oils by Rigid Framework Substituents. Issue 12 (14th October 2014)

• Record Type: Journal Article
• Authors: Christl, Josefine T.; Roesle, Philipp; Stempfle, Florian; Müller, Gerhard; Caporaso, Lucia; Cavallo, Luigi; Mecking, Stefan
• Is Part Of: ChemSusChem. Volume 7:Issue 12(2014:Dec.)
• Page Start: 3491
• Page End: 3495
• Publication Date: 2014-10-14
• Subjects: Green chemistry -- Periodicals; Sustainable engineering -- Periodicals; Chemistry -- Periodicals; Chemical engineering -- Periodicals; 660
• DOI: 10.1002/cssc.201402441
• Languages: English
• ISSNs: 1864-5631

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The 1, 2‐(CH₂P(1‐adamantyl)₂)₂C₆H₄ (dadpx) coordinated palladium complex [(dadpx)Pd(OTf)₂] (<bold>1</bold>) is a catalyst precursor for the isomerizing methoxycarbonylation of the internal double bond of methyl oleate, with an unprecedented selectivity (96 %) for the linear diester 1, 19‐dimethyl nonadecanedioate. Rapid formation of the catalytically active solvent‐coordinated hydride species [(dadpx)PdH(MeOH)]⁺ (<bold>3‐MeOH</bold>) is evidenced by NMR spectroscopy, and further isolation and X‐ray crystal structure analysis of [(dadpx)PdH(PPh₃)]⁺ (<bold>3‐PPh₃</bold>). DFT calculations of key steps of the catalytic cycle unravel methanolysis as the decisive step for enhanced selectivity and the influence of the rigid adamantyl framework on this step by destabilization of transition states of unselective pathways.</p> </abstract>