Visible-Light-Induced Intramolecular Radical Cyclization for the Synthesis of Benzimidazo-isoquinolineones and Pyrrolidones.

A visible-light-induced radical cyclization of α-brominated amides has been developed to construct benzimidazole[2,1-]isoquinolin-6(5)-ones and pyrrolidonesin in yields up to 97%. The methodology exhibits a certain functional-group compatibility with 43 examples and operational simplicity, offering a rapid and concise approach to obtain five- and six-membered rings under the irradiation of 18 W blue LED. Additionally, large-scale reaction of this method for synthesizing benzimidazo-isoquinolineones and the further transformations to useful pyrrolidones were also conducted and afforded positive results.

Synthesis of Sulfone Methylene-Substituted Indolines by Radical Cascade Cyclization of 2-Alkynylaniline Derivatives.

A radical cascade cyclization of 2-alkynylaniline derivatives with sulfonyl chlorides was developed to construct C3-sulfone methylene-substituted indolines in yields of 21 to 85% with a broad substrate scope under metal- and base-free conditions. This protocol could simultaneously build three new chemical bonds and employ a solvent-radical relay strategy, providing a rapid and concise approach toward an indoline framework. Scale-up reactions of this method and further transformations to afford useful indolines were also demonstrated.

Synthesis of Difluoroarymethyl-Substituted Benzimidazo[2,1-]isoquinolin-6(5)-ones under Mild Conditions.

A highly efficient method for synthesis of difluoroarymethyl-substituted benzimidazo[2,1-]isoquinolin-6(5)-ones using 2-arylbenzoimidazoles with α,α-difluorophenylacetic acid as reaction substrates has been developed through radical cascade cyclization. The advantage of this strategy lies in excellent functional group tolerance to generate the corresponding products in good yields under base- and metal-free conditions.

Stabilizing Effect of Soluplus on Erlotinib Metastable Crystal Form in Microparticles and Amorphous Solid Dispersions.

Microparticles (MPs) and amorphous solid dispersions (SDs) are effective methods to improve the dissolution of insoluble drugs. However, stability is a concern for these two high-energy systems, resulting from high surface area and amorphous polymorph, respectively. As an amphiphilic polymer, Soluplus (SOL) is usually used as a carrier in SDs.

Cu-Catalyzed Dehydrogenative Olefinsulfonation of Alkyl Arenes.

A copper-catalyzed reaction protocol for the dehydrogenation of ethylbenzenes into styrene derivatives has been developed. This reaction procedure proceeded well under mild reaction conditions, providing a practical and efficient strategy for the rapid assembly of biologically and pharmaceutically significant molecules, such as vinyl sulfone. Simple alkyl arenes were functionalized via consecutive β-elimination in the presence of -sulfonylbenzo[]imidazole with broad substrate scope and good functional group tolerance.

Chlorination and ortho-acetoxylation of 2-arylbenzoxazoles.

Efficient and facile catalytic protocols for chlorination and ligand-directed ortho-acetoxylation of 2-arylbenzoxazoles have been developed. The chlorination is not a ligand-directed ortho-functionalization, but an electrophilic substitution process in the benzo ring of the benzoxazole moiety. Meanwhile, the acetoxylation exhibited high regioselectivity for the substrates containing a meta-substituent and occurred at the less sterically hindered ortho-C-H bond of the directing group.