Various types of five-membered heterocyclic compounds such as 2-iminodioxolanes, 2-oxazolidinones, and 2-iminooxazolidines, can be obtained from the cycloaddition of oxiranes with isocyanates or carbodiimides catalyzed by organotin iodide-Lewis base complexes under very mild conditions (40°C, 2h).
A method for producing a cyclic carbamate ester produces the cyclic carbamate ester by reacting an organic compound having at least two halogen atoms per molecule, an amine having at least two hydrogen atoms on a nitrogen atom, and carbon dioxide.
Photo‐ and Cobalt‐Catalyzed Synthesis of Heterocycles via Cycloisomerization of Unactivated Olefins
作者:Henry Lindner、Willi M. Amberg、Tristano Martini、David M. Fischer、Eléonore Moore、Erick M. Carreira
DOI:10.1002/anie.202319515
日期:2024.5.6
A general, intramolecular cycloisomerization of unactivated olefins with pendant N-, O-, and C- nucleophiles is reported. The reaction proceeds under mild conditions, yielding a number of different heterocycles including, but not limited to, pyrrolidines, piperidines, oxazolidinones, and lactones. Use of both a benzothiazinoquinoxaline as organophotocatalyst and a Co-salen catalyst obviates the need
报道了未活化烯烃与侧链N -、 O - 和C - 亲核试剂的一般分子内环异构化。该反应在温和条件下进行,产生许多不同的杂环,包括但不限于吡咯烷、哌啶、恶唑烷酮和内酯。使用苯并噻嗪喹喔啉作为有机光催化剂和Co-salen催化剂消除了对化学计量氧化剂或还原剂的需要。
2-Oxazolidinones from an N-dealkylation reaction of phosgene with dialkylaminoalkanols. Isolation and reactivities of an N-acyl quaternary ammonium intermediate