Carbon dioxide pressure induced heterogeneous and homogeneous Heck and Sonogashira coupling reactions using fluorinated palladium complex catalysts

Palladium-catalyzed Sonogashira coupling reactions in γ-valerolactone-based ionic liquids

It was demonstrated that the γ-valerolactone-based ionic liquid, tetrabutylphosphonium 4-ethoxyvalerate as a partially bio-based solvent can be utilized as alternative reaction medium for copper- and auxiliary base-free Pd-catalyzed Sonogashira coupling reactions of aryl iodides and functionalized acetylenes under mild conditions. Twenty-two cross-coupling products were isolated with good to excellent yields (72–99%) and purity (>98%). These results represent an example which proves that biomass-derived safer solvents can be utilized efficiently in common, industrially important transformations exhibiting higher chemical and environmental efficiency.

Synthesis, Luminescence, and Structure of a Polymorphic Polyfluorinated Diiodoplatinum(II) Diimine Complex

PtI₂(5,5'-bis(HCF₂CH₂OCH₂)-2,2'-bpy)], 55-2FH-PtI₂, is the first example of a substituted fluorinated diiodoplatinum diimine complex that exhibits polymorphism. The complex, upon recrystallization, forms two different polymorphs, denoted as α and β forms. The luminescence of the α and β forms are the same in glassy solution at 77 K; however, in the solid state, they differ significantly. The major difference between them lies in the solid-state packing of the crystalline structure. The α form is a square planar polyfluorinated PtI₂-containing complex. Its extended herringbone structure consists of two neighboring stacked bipyridyl planes that do not overlap. The α form emits stronger than its parent molecule, [PtI₂bpy], and much stronger than the β polymorph. The β form has a slight tetrahedral distortion about the metal center that ultimately changes the geometry of the complex and decreases the d-orbital splitting from square planar. Furthermore, overlapping bipyridine rings in the extended structure of the β form quench the emission thus resulting in a lower energy emission. Additionally, the β form shows only one type of C-H···O intermolecular stacking interaction that can cause the moderate distortion of the metal core.

Intercalated polyfluorinated Pd complexes in α-zirconium phosphate for Sonogashira and Heck reactions

A direct method was used to effectively intercalate the short fluorous-ponytailed Pd complexes into the ZrP gallery, and the resulting Pd intercalated ZrP could be used as a recoverable catalyst for Sonogashira and Heck reactions.