Synthesis of α,β-unsaturated ketones through nickel-catalysed aldehyde-free hydroacylation of alkynes

α,β-Unsaturated ketones are common feedstocks in functional materials, pharmaceuticals and natural compounds. Transition metal-catalysed hydroacylation reactions of alkynes using aldehydes have been widely applied for the atom-economical synthesis of α,β-unsaturated ketones through chemoselective aldehydic C–H activation. However, previous hydroacylation reactions using rhodium, cobalt, or ruthenium catalysts require chelating moiety-bearing aldehydes to prevent undesired decarbonylative product via an unstable acyl-metal-H complex. Herein, we report a nickel-catalysed reductive and anti-Markovnikov selective coupling process to afford non-tethered E-enones from terminal alkynes through an acyl-nickel-thiopyridine complex in the presence of zinc metal as a reducing agent. Utilization of a thioester as an acylating agent and water as a hydrogen donor enables this mechanistically distinctive and aldehyde-free hydroacylation of terminal alkynes under mild reaction conditions at room temperature, with a broad substrate scope including versatile functional groups and even simple aryl and alkyl moieties.

Cerium Incorporated Nanocrystalline ZSM-5: An Efficient Catalyst for Friedel Crafts Acylation of Toluene

In this paper, the application of cerium modified nanocrystalline zeolite ZSM-5 as catalyst for Friedel Crafts acylation of toluene was investigated and compared with nanocrystalline ZSM-5. The acylating agent used was acetic anhydride. The zeolite samples were characterized by means of Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX), Thermal analysis, ammonia temperature-programmed desorption (NH3-TPD) and Nitrogen sorption analysis. The results show an enhanced Lewis acidity, pore volume and surface area for cerium modified ZSM-5 providing a superior accessibility for acetic anhydride and toluene to the active sites compared to the unmodified one, thereby leading to 93% conversion of acetic anhydride, which was higher than that of unmodified ZSM-5 sample.

N-acylation of Phenylacetic Acid Amide - Synthesis and Study of Thermodynamic Reaction Characteristics

The aim of this study is the synthesis of N-acylated derivatives of phenylacetic acid amide and the investigation of the correlation between product yields and the nature of the acylating agent. The reaction was carried out in an acidic environment, adding acid anhydrides to the substance, which differ in the length and branching of the carbon chain. The resulting products are of considerable interest both as biologically active compounds and as starting materials for the preparation of pyrimidin-4(1)-one derivatives.

An efficient way for the N-formylation of amines by inorganic-ligand supported iron catalysis

A green and highly efficient N-formylation of amines using formic acid as the acylating agent by iron catalysis with excellent selectivity and yields.

Cysteine-To-Lysine Transfer Antibody Fragment Conjugation

The modification of lysine residues with acylating agents has represented a ubiquitous approach to the construction of antibody conjugates, with the resulting amide bonds being robustly stable and clinically validated. However, the conjugates are highly heterogeneous, due to the presence of numerous lysines on the surface of the protein, and greater control of the sites of conjugation are keenly sought. Here we present a novel approach to achieve the targeted modification of lysines distal to an antibody fragment’s binding site, using a disulfide bond as a temporary ‘hook’ to deliver the acylating agent. This cysteine-to-lysine transfer (CLT) methodology offers greatly improved homogeneity of lysine conjugates, whilst retaining the advantages offered by the formation of amide linkages.

Cysteine-To-Lysine Transfer Antibody Fragment Conjugation

The modification of lysine residues with acylating agents has represented a ubiquitous approach to the construction of antibody conjugates, with the resulting amide bonds being robustly stable and clinically validated. However, the conjugates are highly heterogeneous, due to the presence of numerous lysines on the surface of the protein, and greater control of the sites of conjugation are keenly sought. Here we present a novel approach to achieve the targeted modification of lysines distal to an antibody fragment’s binding site, using a disulfide bond as a temporary ‘hook’ to deliver the acylating agent. This cysteine-to-lysine transfer (CLT) methodology offers greatly improved homogeneity of lysine conjugates, whilst retaining the advantages offered by the formation of amide linkages.