Copper-Catalyzed Bifunctionalization/Annulation of Unactivated Alkene with Alkyl Bromides

β-Lactam is a ubiquitous scaffold in bioactive compounds and pharmaceuticals. Herein, we disclose a streamlined method for the construction of β-lactams starting from unactivated alkenes and alkyl bromides via a Cu-catalyzed inter-/intramolecular carboamidation. This reaction proceeded smoothly under mild reaction conditions and exhibited a broad substrate scope and various functional groups. This protocol is not only compatible with 1, 2, and 3° alkyl bromides but also suitable for α-bromo nitrile as well as various benzyl bromides. The mechanism exploration indicated that sequential radical addition/reductive elimination was involved.

One-pot and divergent synthesis of polysubstituted quinolin-2(1H)-ones and oxireno[2,3-c]quinolin-2(1aH,3H,7bH)-ones via sequential Ugi/Knoevenagel condensation/hydrolysis and Ugi/Corey–Chaykovsky epoxidation reactions

A new one-pot and divergent synthesis of multisubstituted quinolin-2(1H)-ones and oxireno[2,3-c]quinolin-2(1aH,3H,7bH)-ones was developed.

4-Aminoalkyl Quinolin-2-one Derivatives via Knorr Cyclisation of ω-Amino-β-Keto Anilides

In a high-yielding and solvent-free procedure N-ethoxycarbonyl protected ω-amino-β-keto anilides undergo Knorr cyclisation in neat polyphosphoric acid to provide straightforward route to 4-aminoalkyl quinolin-2-one derivatives with variable length of the alkyl chain.

Directed Cobalt-Catalyzed C-H Activation to Form C-C and C-O Bonds in One Pot via Three-Component Coupling

Herein, we disclose an efficient cobalt-catalyzed three-component coupling of benzamides, diazo compounds, and tert-butyl hydroperoxide, which provides an efficient approach to construct C(sp²)-C(sp³) and C-O bonds in one-pot accompanied with C-H activation. This protocol features low catalyst loading (4 mol %), the avoidance of additives, and excellent functional group compatibility, providing three-component coupling adducts with high yields under mild conditions (up to 88%). Mechanism studies show that the reaction may involve a radical process.

Organic amine-mediated free-radical carbocyclization reactions of 2,2,2-trihalogeno-substituted N-(2-alkynylphenyl)acetamides

An efficient method for the synthesis of 3-halogeno-substituted 4-benzoylquinolin-2-(1H)-ones from N-(2-alkynylphenyl)-substituted trihaloacetamides has been developed, in which organic amines (TNPA and DIEA) act as the electron donors. In this carbocyclization reaction, a new C-C bond formation occurred regioselectively via a 6-exo-dig radical cyclization. A variety of useful functional groups are compatible with the reaction conditions. In this process, readily removable organic amines were employed and no heavy metal catalysts were required.

Electrophilic carbocyclization reactions of 2-(2-alkynylphenyl)amino-1,4-naphthoquinones

Electrophilic carbocylization reactions for the synthesis of 5H-benzo[b]naphtho [2,3-f]azepine-6,11-diones are described.