An Improved Synthesis of 1,2,3,4-Tetrahydroisoquinolines via Intramolecular Cyclization of N-Acyl-N-(aryl)methyl-2-(phenylsulfinyl)ethylamine by Pummerer Reaction.
An Improved Synthesis of 1,2,3,4-Tetrahydroisoquinolines via Intramolecular Cyclization of N-Acyl-N-(aryl)methyl-2-(phenylsulfinyl)ethylamine by Pummerer Reaction.
and a catalytic amount of AIBN in boiling benzene caused 5-exo cyclization of allylic O-stannyl ketyl radicals generated by addition of Bu3Sn· on the amide-oxygen atoms to provide γ-lactams 2a–h after acidic workup. When enamide 1d was treated with Bu3SnH in the presence of AIBN followed by aldehydes 3a–d, sequential radicalcyclization and aldol reactions occurred to afford anti-adducts 4a–d and syn-adducts
Decarboxylative ring-opening of 2-oxazolidinones: a facile and modular synthesis of β-chalcogen amines
作者:Fábio Z. Galetto、Cleiton da Silva、Ricardo I. M. Beche、Renata A. Balaguez、Marcelo S. Franco、Francisco F. de Assis、Tiago E. A. Frizon、Xiao Su
DOI:10.1039/d2ra06070a
日期:——
We report herein the synthesis of primary and secondary β-chalcogen amines through the regioselective ring-opening reaction of non-activated 2-oxazolidinones promoted by in situ generated chalcogenolate anions. The developed one-step protocol enabled the preparation of β-selenoamines, β-telluroamines and β-thioamines with appreciable structural diversity and in yields of up to 95%.
Dawson, Journal of the American Chemical Society, 1933, vol. 55, p. 2071
作者:Dawson
DOI:——
日期:——
The use of 2-oxazolidinones as latent aziridine equivalents. 2. Aminoethylation of aromatic amines, phenols, and thiophenols
作者:Graham S. Poindexter、Donald A. Owens、Peter L. Dolan、Edmund Woo
DOI:10.1021/jo00049a037
日期:1992.11
The utility of 2-oxazolidinones 1 as latent, carboxylated aziridine functionalities was examined. Reaction of 2-oxazolidinone (1a), 3-methyl-2-oxazolidinone (1b), 3-(phenylmethyl)-2-oxazolidinone (1c), 3-phenyl-2-oxazolidinone (1d), 4,4-dimethyl-2-oxazolidinone (1e), and 5-ethyl-2-oxazolidinone (1f) with aromatic amine salts, phenol, or thiophenols at elevated temperatures (> 130-degrees-C) afforded aminoethylated adducts. The aminoethylation occurred with concomitant loss of carbon dioxide to furnish variously substituted N-aryl-1,2-ethanediamines 4, 1-(2-phenoxyethyl)-2-imidazolidinone (8), or 2-(arylthio)ethanamines 9 on reactions of 1 with aromatic amine salts, phenol, and thiophenols, respectively. Imidazolidinone 8 is believed to be a secondary reaction product resulting from the condensation of the initially formed 2-phenoxyethanamine with starting oxazolidinone 1a. The aminoethylation reaction did not proceed with aliphatic amine hydrochlorides or alkyl mercaptans. Preliminary mechanistic pathways for these ring openings were also investigated employing a specific, C-5 deuterium-labeled oxazolidinone 1b-d2. Ring-opening experiments of 1b-d2 with N-methylaniline hydrochloride suggest reaction can occur through either a dioxazolinium 5 and/or an aziridinium 6 intermediate. In contrast, reaction of 1b-d2 with thiophenol suggests ring-opening to proceed only via the dioxazolinium pathway.