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An efficient and regioselective palladium-catalyzed oxidative cross-coupling reaction between thiazolo[3,2-b]-1,2,4-triazoles and alkenes has been developed. This protocol provides easy access to a variety of functionalized thiazolo[3,2-b]-1,2,4-triazole derivatives.

A highly regioselective oxidative olefination of imidazo[1,2-a]pyridines with acrylates has been accomplished in the presence of ruthenium catalysts to form only the C-3 coupling products. The oxidative olefination has provided step economical access to diversely substituted imidazo[1,2-a]pyridine derivatives with excellent C-3 regioselectivity and E-stereoselectivity.

A convenient method to synthesize vinylfurans through a palladium-catalyzed cyclization/1,2-H shift sequence under mild conditions is described. This is an efficient strategy to synthesize 2-vinylfurans from ene–yne ketones, and the corresponding products are obtained in good yields.

A variety of functionalized furans were synthesized by way of a ruthenium-catalyzed coupling reaction of 2,3,5-trisubstituted furans with aryl halides through C–H bond cleavages. The feature of the reaction was facilitative preparation of furan derivatives good functional group tolerance. All reactions gave the desired products in moderate to good yields (56–89%) in the presences of [RuCl 2 (p-cymene)] and K 2 CO 3 in NMP at 120 °C.

Pd-catalyzed direct arylation of 2,3,5-trisubstituted furanswith a variety of aryl iodides or aryl bromides that showed highactivity with reasonably broad scope was developed. Under optimalconditions, all reactions gave the desired products in moderateto good yields.

A highly regioselective method for the palladium-catalyzed direct cross-coupling of imidazo[1,2-a]pyridines with arylboronic acids has been developed by using O2 as oxidant. This process can be applied to a wide range of imidazo[1,2-a]pyridines and arylboronic acids with excellent C-3-regioselectivity. It provides a new way for developing C C bond-forming processes of multisubstituted imidazo[1,2-a]pyridines, which are common structural motifs in natural products and pharmaceuticals.

Excellent E-stereoselectivity is obtained in the reaction with acrylates as olefination reagent, whereas the reaction of acrylonitrile gives a mixture of E/Z-isomers.

The Pd-catalyzed oxidative coupling of thiazolotriazoles and alkenes proceeds with high regio- and stereoselectivity to produce (E)-isomers (III) and (V) exclusively.

The authors present a new one-pot cyclization reaction to the corresponding furan derivatives which proceeds under mild conditions.

We have developed an efficient Pd-catalyzed regioselective arylation of substituted imidazo[1,2-a]pyridines with aryl chlorides, which is rarely reported. This methodology has been successfully applied to the synthesis of a variety of substituted imidazo[1,2-a]pyridine core π systems which exhibit a wide range of biological activities in many drugs.

A convenient method for the copper(I)-catalyzed arylation of substituted imidazo[1,2-a]pyridine has been developed. This method is applicable to a variety of aryl electrophiles, including bromides, iodides, and triflates. It represents the first general process for C-3 arylation of substituted imidazo[1,2-a]pyridine by Cu(I) catalysis to construct various functionalized imidazo[1,2-a]pyridine core π-systems.

A convenient method for the copper(I)-catalyzed arylation of substituted imidazo[1,2-a]pyridine has been developed. This method is applicable to a variety of aryl electrophiles, including bromides, iodides, and triflates. It represents the first general process for C-3 arylation of substituted imidazo[1,2-a]pyridine by Cu(I) catalysis to construct various functionalized imidazo[1,2-a]pyridine core π-systems.

Aryl iodides bearing electron-rich or electron-withdrawing groups at the aromatic ring give comparable yields of the tetrasubstituted furans.

Optimized conditions are developed for the preparation of a series of tetrasubstituted furans.

We have developed an efficient Pd-catalyzed regioselective arylation of substituted imidazo[1,2-a]pyridines with aryl chlorides, which is rarely reported. This methodology has been successfully applied to the synthesis of a variety of substituted imidazo[1,2-a]pyridine core π systems which exhibit a wide range of biological activities in many drugs.