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A novel strategy for the synthesis of 4-amino-3-cyano-2,2′- and 5′-amino-4′-cyano-2,3′-bipyrroles via readily available 1-amino-3-imino-3H-pyrrolizine-2-carbonitriles has been developed. The rearrangement leading to 5′-amino-4′-cyano-2,3′-bipyrroles involves formation of the intermediate aziridine, which undergoes other side ring-opening.

The CN-functionalized pyrrole(indole)-3(2H)-furanone derivatives are readily synthesized via the domino reaction of diverse pyrrole(indole) carboxylic acids with tertiary cyanopropargylic alcohols (Et3N, MeCN, MW reactor, 100 °C, 1.2 atm) in up to 93% yield.

Ketones with bulky aromatic, heteroaromatic and ferrocene substituents react with acetylene in the presence of a KOH/DMSO super-base suspension (90 °C, 15 min) to give polysubstituted furans in up to 86 % isolated yields in a one-pot fashion. This assembly of the furan scaffold involves a domino sequence in which one molecule of ketone reacts with two molecules of acetylene.

A method for the iododifluoromethylation of aromatic aldehydes using (bromodifluoromethyl)trimethylsilane (Me3SiCF2Br) is described. The selective formation of the CF2I group is based on using sodium iodide, with the sodium serving as a scavenger of bromide and iodide serving as a nucleophile with respect to difluorocarbene. The primary CF2I-addition products can undergo HI-elimination or iodine/zinc exchange followed by allylation in a one-pot manner.

A new gem-difluorinated silicon reagent bearing a pyrrolidine dithiocarbamate substituent was prepared by the reaction of (bromodifluoromethyl)trimethylsilane with the corresponding potassium dithiocarbamate. The obtained reagent was employed in the nucleophilic addition to aldehydes and ketones.

The title reaction proceeds under mild conditions to form the corresponding products with high regio- and stereoselectivity.

5-Acylethynylpyrrole-2-carbaldehydes have been synthesized from the protected pyrrole-2-carbaldehydes by their transition-metal-free topochemical mechanoactivated ethynylation with acylbromoacetylenes in a solid Al2O3 medium (room temperature, 6 h, 41–54% yields).

Significantly shorter reaction times together with higher yields are the benefits when the addition reaction is carried out under solvent-free conditions.

A method for the synthesis of gem-difluorinated nitroso compounds is described. The reaction involves interaction of organozinc reagents with (bromodifluoromethyl)trimethylsilane followed by nitrosation of difluorinated organozinc species with an n-butyl nitrite/chlorotrimethylsilane system.

Under catalyst- and solvent-free conditions, secondary phosphine selenides easily add to diverse alkenes [acrylonitrile, allyl alcohol, styrene, vinyl ethers, vinyl sulfides, and trimethyl(vinyl)silane] at 80 °C (3–20 h) to give anti-Markovnikov adducts in 70–95% yield.

A new method has been developed for the synthesis of benzimidazole carbothioamides, which have potential pharmacological activity, by a three-component reaction of 1-substituted benzimidazoles, phenylcyanoacetylene, and methyl, allyl, or phenyl isothiocyanates. The reaction of these components proceeds under mild conditions in acetonitrile at 50-55°C for 12-20 h and stereoselectively leads to N-[(Z)-2-cyano-1-phenylethenyl]benzimidazole-2-carbothioamides in 43-82% yield.

The facile protocol allows the catalyst- and solvent-free addition of phosphine sulfides to terminal and internal alkenes.

Gaseous phosphine reacts with p-methoxystyrene at 70°C to afford bis(methoxyphenylethyl)phosphine (II) in high yield.

The interaction of cyclic nitronate esters with silyl enolates in the presence of trimethylsilyl triflate leads to the formation of five-membered heterocycles, isoxazoles orN-hydroxypyrrol.

Silylation of γ,γ-bis(alkyloxycarbonyl)-β-aryl- and γ,γ-bis(alkyloxycarbonyl)-β-alkyl-substituted aliphatic nitro compounds proceeds stereoselectively to give the corresponding N,N-bis(trimethylsilyloxy)aminocyclopropanes in high yields. These compounds can be used as synthetic equivalents of nitrosocyclopropanes.

Cyclic six-membered nitronates 1 are involved in diastereoselective C-C coupling reactions with various nucleophiles in the presence of either catalytic or stoichiometric amounts of TBDMSOTf to give the previously unknown N-siloxytetrahydrooxazines. The intermediacy of N,N-bis(oxy)iminium cations was proven by NMR data.