Herein, we report the stereoselective synthesis of (1 + n)-membered cycloalkane from methyl ketone and 1,n-diol. A manganese(I) complex bearing a phosphine-free ligand catalyzed the reaction, which involved the formation of two C−C bonds via a sequence of intermolecular-and intramolecular-borrowing hydrogenation reactions. It produces 2 mol of water as the sole byproduct, making the process atom economical and environmentally benign. Multisubstituted cycloalkanes were obtained in good to excellent yields with very high selectivities. A thorough mechanistic analysis by high-level DFT computation rationalizes the choice of the pincer and establishes the role of hemilability of the ligand for this efficient transformation.

A CAO inspired catalyst catalyzed the cascade aerobic oxidation of primary and secondary amines for the synthesis of quinazolin-4(3H)-one core in high yields. Like the natural CAOs, a copper ion improves the o-quinone cofactor's catalytic activity.

A sustainable boron-based catalytic approach for chemoselective N-alkylation of primary and secondary aromatic amines and amides with primary, secondary, and tertiary benzylic alcohols has been presented. The metal-free protocol operates at low catalyst loading, tolerates several functional groups, and generates H2O as the sole byproduct. Preliminary mechanistic studies were performed to demonstrate the crucial role of boron catalyst for the activation of the intermediate dibenzyl ether and to identify the rate-determining step.

Herein, we report on manganese-catalyzed regioselective Markovnikov addition and [2+2+2] cycloaddition of 2-carbonyl indanones with terminal alkynes. This method provides an efficient approach for the construction of all-carbon quaternary centers and complex polycyclic hydrocarbon frameworks by the formation of new carbon–carbon single bonds in a regio- and stereoselective manner. Preliminary mechanistic experiments involving deuterium labeling, kinetic, catalytic, and stoichiometric reactions with plausible intermediates were performed to shed light on the reaction mechanism.

We explored the bioinspired o-quinone cofactor catalyzed aerobic primary amine dehydrogenation for a cascade olefination reaction with nine different methyl N-heteroarenes, including pyrimidines, pyrazines, pyridines, quinolines, quinoxolines, benzimidazoles, benzoxazoles, benzthiazoles, and triazines. An o-quinone catalyst phd (1,10-phenanthroline-5,6-dione) combined with a Brønsted acid catalyzed the reaction. N-Heteroaryl stilbenoids were synthesized in high yields and (E)-selectivities under mild conditions using oxygen (1 atm) as the sole oxidant without needing transition-metal salt, ligand, stoichiometric base, or oxidant.