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γ‐methylene C(sp3)−H functionalization of linear free carboxylic acids remains a significant challenge. Here in we report a Pd(II)‐catalyzed tandem γ‐arylation and γ‐lactonization of aliphatic acids enabled by a L,X‐type CarboxPyridone ligand. A wide range of γ‐arylated γ‐lactones are synthesized in a single step from aliphatic acids in moderate to good yield. Arylated lactones can readily be converted into disubstituted tetrahydrofurans, a prominent scaffold amongst bioactive molecules. [ABSTRACT FROM AUTHOR]

γ‐methylene C(sp3)−H functionalization of linear free carboxylic acids remains a significant challenge. Here in we report a Pd(II)‐catalyzed tandem γ‐arylation and γ‐lactonization of aliphatic acids enabled by a L,X‐type CarboxPyridone ligand. A wide range of γ‐arylated γ‐lactones are synthesized in a single step from aliphatic acids in moderate to good yield. Arylated lactones can readily be converted into disubstituted tetrahydrofurans, a prominent scaffold amongst bioactive molecules. [ABSTRACT FROM AUTHOR]

A method of para‐selective borylation of aromatic amides is described. The borylation proceeded via an unprecedented substrate–ligand distortion between the twisted aromatic amides and a newly designed ligand framework (defa) that is different from the traditionally used ligand (dtbpy) for the C−H borylation reactions. The designed ligand framework (defa) has led to the development of a new type of catalytic system that shows excellent para selectivity for a range of aromatic amides. Moreover, the designed ligand has shown excellent reactivity and selectivity for a range of heterocyclic aromatic amides. The identification of key transition states and intermediates using the DFT computations associated with the three regio‐isomeric pathways revealed that the most efficient catalytic pathway with the defa ligand leads to the para borylation while in the case of bpy the borylation at the para and meta sites compete. [ABSTRACT FROM AUTHOR]

A method of para‐selective borylation of aromatic amides is described. The borylation proceeded via an unprecedented substrate–ligand distortion between the twisted aromatic amides and a newly designed ligand framework (defa) that is different from the traditionally used ligand (dtbpy) for the C−H borylation reactions. The designed ligand framework (defa) has led to the development of a new type of catalytic system that shows excellent para selectivity for a range of aromatic amides. Moreover, the designed ligand has shown excellent reactivity and selectivity for a range of heterocyclic aromatic amides. The identification of key transition states and intermediates using the DFT computations associated with the three regio‐isomeric pathways revealed that the most efficient catalytic pathway with the defa ligand leads to the para borylation while in the case of bpy the borylation at the para and meta sites compete. [ABSTRACT FROM AUTHOR]

A new concept for the meta‐selective borylation of aromatic amides is described. It has been demonstrated that while esters gave para borylations, amides lead to meta borylations. For achieving high meta selectivity, an L‐shaped bifunctional ligand has been employed and engages in an O⋅⋅⋅K noncovalent interaction with the oxygen atom of the moderately distorted amide carbonyl group. This interaction provides exceptional control for meta C−H activation/borylation. L‐Shaped: A new concept for the meta borylation of aromatic amides is described. It has been shown that while esters give para borylations, amides result in meta borylations. For achieving high meta selectivity, an L‐shaped ligand is used and engages in an O⋅⋅⋅K noncovalent interaction with the moderately distorted amide carbonyl group, providing exceptional control for meta C−H activation/borylation. [ABSTRACT FROM AUTHOR]

A new concept for the meta‐selective borylation of aromatic amides is described. It has been demonstrated that while esters gave para borylations, amides lead to meta borylations. For achieving high meta selectivity, an L‐shaped bifunctional ligand has been employed and engages in an O⋅⋅⋅K noncovalent interaction with the oxygen atom of the moderately distorted amide carbonyl group. This interaction provides exceptional control for meta C−H activation/borylation. [ABSTRACT FROM AUTHOR]

Remote C−H functionalization of heterocyclic biaryls will be of great importance in synthesis and medicinal chemistry. Through adjusting the geometric relationship of the directing atom and target C−H bonds, two new catalytic templates have been developed to enable the functionalization of the more hindered ortho‐C−H bonds of heterobiaryls bearing directing heteroatom at the meta‐ or para‐positions, affording unprecedented site‐selectivity. The use of template chaperone also overcomes product inhibition and renders the directing templates catalytic. The utility of this protocol was demonstrated by olefination of heterocyclic biaryls with various substituents, overriding conventional steric and electronic effects. These ortho‐C−H olefinated heterobiaryls are sterically hindered and can often be challenging to prepare through aryl‐aryl coupling reactions. [ABSTRACT FROM AUTHOR]

Remote C−H functionalization of heterocyclic biaryls will be of great importance in synthesis and medicinal chemistry. Through adjusting the geometric relationship of the directing atom and target C−H bonds, two new catalytic templates have been developed to enable the functionalization of the more hindered ortho‐C−H bonds of heterobiaryls bearing directing heteroatom at the meta‐ or para‐positions, affording unprecedented site‐selectivity. The use of template chaperone also overcomes product inhibition and renders the directing templates catalytic. The utility of this protocol was demonstrated by olefination of heterocyclic biaryls with various substituents, overriding conventional steric and electronic effects. These ortho‐C−H olefinated heterobiaryls are sterically hindered and can often be challenging to prepare through aryl‐aryl coupling reactions. [ABSTRACT FROM AUTHOR]

A method of para‐selective borylation of aromatic amides is described. The borylation proceeded via an unprecedented substrate–ligand distortion between the twisted aromatic amides and a newly designed ligand framework (defa) that is different from the traditionally used ligand (dtbpy) for the C−H borylation reactions. The designed ligand framework (defa) has led to the development of a new type of catalytic system that shows excellent para selectivity for a range of aromatic amides. Moreover, the designed ligand has shown excellent reactivity and selectivity for a range of heterocyclic aromatic amides. The identification of key transition states and intermediates using the DFT computations associated with the three regio‐isomeric pathways revealed that the most efficient catalytic pathway with the defa ligand leads to the para borylation while in the case of bpy the borylation at the para and meta sites compete. [ABSTRACT FROM AUTHOR]

This work reports on an extensive investigation of the physicochemical properties, engine performance, exhaust emissions, and fundamental energy and exergy parameters of waste‐plastic oils blended with an additive, diethyl ether and diesel. A four‐stroke single‐cylinder diesel engine was used for the engine experiments. The seven fuels in this study include a neat diesel, a neat waste plastic oil, two binary blends of diesel‐waste plastic oil, and three ternary blends of diesel with waste plastic oil and diethyl ether. The justification for selecting diethyl ether was to augment fuel properties in the blend and to further reduce emissions. The reasons for choosing waste plastic are not only to harness energy from waste plastic but also to offer an effective solution to the plastic waste management issue. The choice of diesel was to use it as a reference fuel for comparison with other fuels. Fuel properties were observed to be similar, and in some cases better, with the blends. Notable reductions in emissions with identical engine performance and energy and exergy parameters were observed with the five oxygenated blends (plastic oil blends) than with a reference diesel fuel. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]