Rapid, room-temperature self-organization of polyarylated 1-pyrroles from acetylenes and nitriles in the KOBu/DMSO system.

We have discovered that three molecules of arylacetylene are rapidly (15 min) assembled with one molecule of nitrile at room temperature in the KOBu/DMSO system to afford 2-aryl-3-arylethynyl-4-aryl-5-benzyl-1-pyrroles in up to 76% yield. We assume that this unprecedented self-organization process involves the cascade addition of acetylenic carbanions, first to the CN, then to the CC and CC bonds of the intermediates, followed by pyrrole ring closure the intramolecular nucleophilic addition of the NH functional group to the CC bond of the final intermediates.

Synthesis of Functional Polyesters -(2,3-epoxypropyl)-4,5,6,7-tetrahydroindole by Anionic Ring-Opening Polymerization.

The functional polyethers of -(2,3-epoxypropyl)-4,5,6,7-tetrahydroindole (in up to 61% yield, M = 8.7-11.7 kDa) and copolymers with ethylene glycol methylglycidyl ether (M = 5.

Diastereomerically pure rarely functionalized alkenoyl dihydropyrans, 1,6-diketones, and cyclopentanes from acetylene gas and ketones.

Pure ()-alkenoyl dihydropyrans are stereoselectively assembled from 2-acetyl-3,4-dihydropyrans (products of one-pot self-organization of acetylene gas and ketones) and aromatic aldehydes (52-86% yields). Furthermore, ()-alkenoyl dihydropyrans undergo ring opening (acid hydrolysis) to afford 5-hydroxy-1,6-diketones (44-67% yields) and acetyl-2-()-styryl-2,3-dihydroxycyclopentanes (19-32% yields), both as single diastereomers.

Oxaazabicyclooctene Oxides, Another Type of Bridgehead Nitrones: Diastereoselective Assembly from Acetylene Gas, Ketones, and Hydroxyl Amine.

Unique bridgehead nitrones, 8-oxa-6-azabicyclo[3.2.1]oct-6-ene 6-oxides, have been assembled diastereoselectively via acetyldihydropyrans, products of one-pot self-organization of two molecules of ketones and two molecules of acetylene, which after oximation undergo acid-catalyzed ring closure.

Toward Acetylene Renaissance: Functionally Rich N-Aminoindoles from Acetylene Gas, Ketones, and Hydrazines in Two Steps.

A straightforward acetylene-based scalable strategy for the synthesis of highly functionalized N-aminoindoles has been discovered. This pot-, atom-, step-, and energy-economic strategy includes two simple stages: (i) a one-pot multimolecular (2 + 2) diastereoselective assembly of 6,8-dioxabicyclo[3.2.

Acetylene-based two-step diastereoselective synthesis of bridgehead dihydro-oxadiazines using ketones and hydrazine as the only reactants.

Pharmaceutically related bridgehead dihydro-1,3,4-oxadiazines are synthesized in up to 94% yield by the acid-catalyzed diastereoselective reaction of hydrazine hydrate with 6,8-dioxabicyclo[3.2.1]octanes (6,8-DOBCOs), the products of the superbase-promoted self-organization of acetylene with ketones.

Exploring Acetylene Chemistry: A Transition Metal-Free Route to Dienyl 6,8-Dioxabicyclo[3.2.1]octanes from Ketones and Acetylenes.

Dienyl derivatives of 6,8-dioxabicyclo[3.2.1]octanes, closely related to naturally abundant molecules, have been synthesized from 2-acetyl-3,4-dihydropyrans (readily available from ketones and acetylene in two steps), which further add to aryl(hetaryl)acetylenes in the KOBu/DMSO superbase system (105 °C, 1.

A One-Pot Synthesis of 2-Aminopyrimidines from Ketones, Arylacetylenes, and Guanidine.

The three-component reaction of ketones, arylacetylenes, and guanidine catalyzed by the KOBu/DMSO system leads to 2-aminopyrimidines in up to 80% yield. Depending on structure of the starting ketones, the aromatization of intermediate dihydropyrimidines occurs either with loss of hydrogen molecules or methylbenzenes. The latter process takes place in the ketones, in which one of the substituents is not a methyl group.

Synthesis of Acyl Terphenyls and Higher Polyaromatics via Base-Promoted C-H Functionalization of Acetylarenes with Arylacetylenes.

KO(t)Bu/DMSO-promoted C-H functionalization of acetylarenes with arylacetylenes (100 °C, 30 min), generating β,γ-ethylenic ketones, triggers upon further heating (100 °C, 4 h, with or without acidifying additive) the cascade assembly of acyl terphenyls and higher polyaromatics in good yields.

A one-pot approach to Δ2-isoxazolines from ketones and arylacetylenes.

The sequential reaction of ketones with arylacetylenes and hydroxylamine in the presence of KOBu(t)/DMSO followed by the treatment of the reaction mixture with H(2)O and KOH leads to Δ(2)-isoxazolines in up to 88% yield.