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An ultrasound-assisted synthesis of functionalized symmetrical biaryls with electron-withdrawing or electron-donating substituents is described and illustrated by the palladium-catalyzed detelluration of 1,2-diarylditellanes. This procedure offers easy access to symmetrical biaryls in short reaction time and the products are achieved in good to excellent yields.

Herein, we describe a convenient method for the synthesis of symmetrical 1,3-dienes employing an oxidative palladium-catalyzed homocoupling of potassium alkenyltrifluoroborates providing products in good yields relative to existing methodologies. This is the first report of a cross-dimerization of potassium alkenyltrifluoroborates.

An ultrasound-assisted synthesis of symmetrical 1,3-diyne compounds with electron-withdrawing or -donating substituents is described and illustrated by the palladium-catalyzed homocoupling reaction of n-butyl alkynyltellurides. This procedure offers easy access to 1,3-diynes in very short reaction times, and the products are achieved in good to excellent yields.

The oxidation of geminal biaryl ethenes 3 and 1,3-enynes 5 using m-chloroperbenzoic acid in dichloromethane at room temperature presents a catalyst-free approach for the synthesis of functionalized benzophenones 4 and ynones 6, respectively.

A general, highly efficient synthesis of arylated benzenes from simple stitching of α-oxo-ketene-S,S-acetals and functionalized deoxybenzoins via a ‘lactone intermediate’ is described. This procedure offers easy access to highly functionalized arylated benzenes containing sterically demanding groups in good to excellent yields. The advantage of the procedure lies in the fabrication of arylated benzenes with desired conformational flexibility along the molecular axis at room temperature and in a transition metal-free environment through easily accessible precursors.

An ultrasound-assisted synthesis of functionalized vinylic chlorides is described by palladium-catalyzed cross-coupling reaction of potassium aryltrifluoroborate salts and (Z)-2-chloro vinylic tellurides. This procedure offers easy access to vinylic chlorides architecture that contains sterically demanding groups in good yields.

2H-Pyran-2-ones are useful precursors for the synthesis of various aromatic and heterocyclic compounds. In this Letter, we describe substituent-controlled direct access to functionalized 4-(2-oxo-1,2-diarylethyl)-5,6-diaryl-pyran-2-ones by stirring a mixture of 3-cyano-5,6-diaryl-2H-pyran-2-ones and functionalized deoxybenzoins through an unusual decyanation reaction. Under similar reaction conditions, the reactions of 3-carbomethoxy-5,6-diaryl-2H-pyran-2-ones with either substituted acetophenones or deoxybenzoins led to the synthesis of pyrano[3,4-c]pyran-1,8-diones in excellent yields.

A regioselective synthesis of α-methylstyrenes with electron-withdrawing or -donating substituents is described and illustrated by carbanion-induced ring transformation of 2H-pyran-2-one with mesityl oxide in excellent yield. The potential of the reaction lies in the creation of an aromatic ring possessing an isopropenyl unit from six-membered lactones at room temperature under mild reaction conditions.

A regioselective synthesis of unsymmetrical biaryls with electron withdrawing or donating substituents is described and illustrated by carbanion-induced ring transformation of 6-aryl-α-pyrones with methoxyacetone in excellent yield. Our methodology is an alternative to classical organometal-catalyzed aryl–aryl coupling reactions and can be applied to the synthesis of functionally demanding naphthyl biaryls for the development of new ligands for asymmetric synthesis.

Described herein is a one-pot synthesis of α,β-epoxy ketones using a palladium-catalyzed epoxidation–oxidation sequence. Functionalized terminal allylic alcohols are treated with m-CPBA under mild reaction conditions to obtain the α,β-epoxy ketones. The main benefit of this approach is that the epoxidation of the terminal double bond and the oxidation of the secondary alcohol occured in the same reaction under mild reactions and both electron-donating and electron-withdrawing functionalities are tolerated in the reaction sequence.

An expeditious synthesis of unsymmetrical biaryls functionalized with electron-withdrawing or -donating substituents is described and illustrated by the carbanion-induced ring transformation of 2H-pyran-2-ones with malononitrile in excellent yields.