Figure 3: Palladium-catalysed methoxycarbonylation of tetramethylethylene 1a in the presence of various ligands.
From: Highly active and efficient catalysts for alkoxycarbonylation of alkenes
Molecular structures of L3 and its palladium complexes: (a) L3, (b) Pd(L3)(dba), and (c) [Pd(L3)(allylic)]OTf. Hydrogen atoms are omitted for clarity. Displacement ellipsoids correspond to 30% probability. Reaction conditions: 1a (4.0 mmol), Pd(acac)2 (0.1 mol%), monodentate ligand (0.8 mol%), bidentate ligand (0.4 mol%), PTSA (1.6 mol%), CO (40 bar), MeOH (2.0 ml), 120 °C, 20 h. When Pd(L3)(dba) or [Pd(L3)(allylic)]OTf was used, L3 (0.3 mol%) was introduced in the catalytic system. The conversion of 1a and the yields of 2a and 3a were determined by GC chromatography using iso-octane as the internal standard. acac, acetylacetonate; dba, dibenzylideneacetone; OTf, trifluoromethanesulfonate.
