Synthesis of Penta-2,4-dien-1-imines and 1,2-Dihydropyridines by Rhodium-Catalyzed Reaction of <i>N</i>‑Sulfonyl-1,2,3-triazoles with 2‑(Siloxy)furans

A rhodium­(II)-catalyzed reaction of <i>N</i>-sulfonyl-1,2,3-triazoles with 2-(siloxy)­furans is reported. Either open-chain penta-2,4-dien-1-imines or cyclic 1,2-dihydropyridines are selectively obtained depending on the ligand on rhodium­(II)

Intramolecular Dearomatizing [3 + 2] Annulation of α‑Imino Carbenoids with Aryl Rings Furnishing 3,4-Fused Indole Skeletons

The rhodium-catalyzed dearomatizing [3 + 2] annulation reaction of 4-(3-arylpropyl)-1,2,3-triazoles is described. It provides a straightforward synthetic pathway from simple 5-aryl-1-alkynes leading to tricyclic 3,4-fused dihydroindoles via the corresponding 1,2,3-triazoles

Direct Production of Enaminones from Terminal Alkynes via Rhodium-Catalyzed Reaction of Formamides with <i>N</i>‑Sulfonyl-1,2,3-triazoles

A rhodium-catalyzed reaction of formamides with <i>N</i>-sulfonyl-1,2,3-triazoles is developed to formulate a new one-pot procedure for the direct synthesis of α-amino enaminones from terminal alkynes

Direct Production of Enaminones from Terminal Alkynes via Rhodium-Catalyzed Reaction of Formamides with <i>N</i>‑Sulfonyl-1,2,3-triazoles

A rhodium-catalyzed reaction of formamides with <i>N</i>-sulfonyl-1,2,3-triazoles is developed to formulate a new one-pot procedure for the direct synthesis of α-amino enaminones from terminal alkynes

Synthesis of Enaminones by Rhodium-Catalyzed Denitrogenative Rearrangement of 1‑(<i>N</i>‑Sulfonyl-1,2,3-triazol-4-yl)alkanols

Enaminones are synthesized by the rhodium­(II)-catalyzed denitrogenative rearrangement reaction of 1-(<i>N</i>-sulfonyl-1,2,3-triazol-4-yl)­alkanols, which are readily prepared from propargylic alcohols and <i>N</i>-sulfonyl azides. Intramolecular 1,2-hydride (or -alkyl) migration occurs with an intermediary α-imino rhodium­(II) carbenoid species generated through denitrogenation of the 1,2,3-triazol-4-yl moiety. The resulting enaminones is converted into various heterocycles with replacement of the <i>N</i>-sulfonyl group

Facile Synthesis of 2,5-Disubstituted Thiazoles from Terminal Alkynes, Sulfonyl Azides, and Thionoesters

A sequential procedure for the synthesis of 2,5-disubstituted thiazoles from terminal alkynes, sulfonyl azides, and thionoesters is reported. A copper­(I)-catalyzed 1,3-dipolar cycloaddition of terminal alkynes with sulfonyl azides affords 1-sulfonyl-1,2,3-triazoles, which then react with thionoesters in the presence of a rhodium­(II) catalyst. The resulting 3-sulfonyl-4-thiazolines subsequently aromatize into the corresponding 2,5-disubstituted thiazoles by elimination of the sulfonyl group