Synthesis of 5-Phenylthiazolamines by Using Thiourea as an α-Bromination Shuttle

Synthesis of deoxybenzoins from β-alkoxy styrenes and arylboronic acids via palladium-catalyzed regioselective Heck-arylation reactions

Palladium-catalyzed synthesis of deoxybenzoin derivatives from styryl ethers and arylboronic acids is reported. The reaction proceeds under mild conditions in the presence of TEMPO and provides the desired products in good to excellent yields. Simple operation, broad substrate scope, and functional group tolerance are the salient features of the developed methodology.

1,1-Oxycarbonation of Terminal Alkynes via Sequential Borylation, 1,2-Migration, and Oxidation with Oxone

Alkynes are readily available and multifunctional synthetic intermediates, but their 1,1-oxofunctionalization remains challenging. Herein, we report a 1,1-oxycarbonation of terminal alkynes to construct ketones through sequential borylation, 1,2-carbon migration, and oxidation with Oxone as the proton source and oxidant. The synthetic potential of this transformation is showcased by the broad functional groups, scale-up synthesis, and diverse product transformations.

Regioselective Hydrodeoxygenation of α-Diketones with Phosphites under Visible-Light Catalysis

Novel regioselective hydrodeoxygenation of α-diketones with phosphites as the deoxygenation reagent was realized via visible-light photoredox catalysis. Broad substrate scope and high functional group compatibility were obtained. Unsymmetric α-diketones were selectively reduced at the carbonyls of higher electrophilicity. This unique regioselectivity compared with available methods makes it a practical complementary approach for the monohydrodeoxygenation of α-diketones.

Photocatalytic regeneration of brominating agent in the visible light-mediated synthesis of imidazo[1,2-a]pyridines

Regenerating the brominating agent by erythrosine B closes a catalytic cycle for the construction of the imidazo[1,2-a]pyridine framework.

Reagent-controlled regiodivergent intermolecular cyclization of 2-aminobenzothiazoles with β-ketoesters and β-ketoamides

Two regiodivergent approaches to intermolecular cyclization of 2-aminobenzothiazoles with β-ketoesters and amides have been developed, controlled by the reagents employed. With the Brønsted base KOt-Bu and CBrCl3 as radical initiator, benzo[d]imidazo[2,1-b]thiazoles are synthesized via attack at the α-carbon and keto carbon of the β-ketoester moiety. In contrast, switching to the Lewis acid catalyst, In(OTf)3, results in the regioselective nucleophilic attack at both carbonyl groups forming benzo[4,5]thiazolo[3,2-a]pyrimidin-4-ones instead.