The preparation of the novel, well-defined [Pd(IPr*)(3-Cl-pyridinyl)Cl 2 ] complex is described. The steric parameters of the ligand as well as its reactivity in the Buchwald−Hartwig amination were directly compared to other [Pd(NHC)(3-Cl-pyridinyl)Cl 2 ] and [Pd(IPr*)(LX)Cl)] precatalysts (LX = cinnamyl or acac). The title complex exhibits similar catalytic activity to [Pd(NHC)(3-Clpyridinyl)Cl 2 ] congeners (NHC = IPr and SIPr) at room temperature. However, it also showed improved reactivity at low catalyst loading and high temperature (as low as 0.025 mol %). On the other hand, it proved to be as efficient as the previously reported [Pd(IPr*)(cinnamyl)Cl] complex, pointing to the most likely existence of a similar catalytically active species.

The copper-catalyzed reaction of allenes with bis(pinacolato)diboron and acyl electrophiles is reported. In this transformation, acyl fluorides have been proven to be more efficient coupling partners than their chloride or carboxylate analogues. The optimized reaction conditions employed were shown to be compatible with a range of commonly used functional groups, thereby allowing the formation of a library of β-boryl β,γ-unsaturated ketones by varying the nature of the allene and acyl fluoride substrates.

A highly effective solvent-free protocol for the Buchwald-Hartwig amination of unactivated aryl chlorides is described. The effect of various [Pd(NHC)] pre-catalyst systems on the reactivity has been studied. [Pd(IPr*)(cin)Cl] is reported as the complex of choice for the transformation

A new method for the synthesis of trifluoromethyl-allenes from easily accessible α-trifluoromethyl-propargyl benzyl ether derivatives following a gold-catalyzed intramolecular hydride transfer has been developed. Various di- and trisubstituted trifluoromethyl-allenes were obtained in good to excellent yields.

We report herein a versatile cooperative dual catalysis reaction based on a Cu(I)/Pd(0) system. Mechanistic investigation shows that every component plays a crucial role in determining the reaction outcome. The reaction is successfully extended to various substrates; such as α,β-unsaturated ketones, malonates and coumarins. The strategy tolerates different substitution patterns and affords good yields for each family of substrates.

Herein, we report the copper-catalyzed domino borylation/aldolisation of methyl 2-fluoroacrylate with carbonyl compounds followed by an elimination to give Morita-Baylis-Hillman (MBH) analogues. The optimal conditions described were shown to be compatible with a wide range of aldehydes and ketones. Unprecedented MBH adducts derived from ketones were efficiently synthesized.

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