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A simple approach to polysubstituted thiophene derivatives is demonstrated. The synthesis is highlighted by the direct [2+2+1] cycloaddition reaction to construct carbon-sulfur and carbon-carbon bonds, without adding oxidizing, reducing and noble metal agents. All tested substrates provided their corresponding thiophene products in high isolated yields under the optimized conditions.

An improved and efficient method for the synthesis of thioamides is presented. For this transformation, dimethylamine as the key intermediate is generated in situ from dimethylformamide (DMF). All the tested substrates produced the desired products with excellent isolated yields.

An efficient and general one-pot procedure for the synthesis of pyrazoles from acid chlorides, terminal alkynes and hydrazines was described via a coupling and cyclocondensation sequence. Acid chlorides coupled with terminal alkynes to give α,β-unsaturated ynones, and in situ converted into pyrazoles by the cycloaddition of hydrazines. The desired pyrazoles were obtained with 15–85% isolated yields.

A novel and convenient one-pot synthesis of multisubstituted pyrimidine analogues via multicomponent reactions is disclosed. This catalyst-free domino reaction proceeded smoothly in good to excellent yields and offered several other advantages including short reaction time, a simple experimental workup procedure, and no toxic byproduct. In addition, the obtained products in our experiments are interesting nitrogen heterocyclic molecules containing alpha- and beta-amino acid blocks.

A facile triphenylphosphine-catalyzed Michael addition of alcohols to acrylic compounds was described. The reaction was carried out in open air at refluxing temperature in the presence of 10 mol% PPh3. Michael addition of saturated and unsaturated alcohols to acrylonitrile or acrylates has been examined. The reaction gave β-alkoxy derivatives with isolated yields of 5%–79%. PPh3 is cheaper and more stable than those trialkylphosphines previously used for the similar reactions, and the products can be easily separated from the reaction mixture via distillation.

A green, simple and effective polymeric organocatalytic system, polymer-supported triphenylphosphine (PS-TPP), for the stereoselective isomerization of α,β-ynones to (E,E)-α,β-γ,δ-dienones is reported here. The catalyst, PS-TPP could be recovered by simple filtration and reused several times with high activity.