Organolanthanide-Catalyzed Carbon-Heteroatom Bond Formation. Observations on the Facile, Regiospecific Cyclization of Aminoalkynes

• Published in: Organometallics Vol. 13; no. 2; pp. 439 - 440
• Main Authors: Li, Yanwu, Fu, Peng-Fei, Marks, Tobin J
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 01.02.1994; Amer Chemical Soc
• Subjects: 400102 - Chemical & Spectral Procedures; 400201 - Chemical & Physicochemical Properties; ALKYNES; AMINES; AROMATICS; CATALYSIS; CHEMICAL BONDS; CHEMICAL REACTIONS; Chemistry; Chemistry, Inorganic & Nuclear; Chemistry, Organic; COMPLEXES; Exact sciences and technology; Heterocyclic compounds; Heterocyclic compounds with only one n hetero atom and condensed derivatives; HYDROCARBONS; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; MAGNETIC RESONANCE; NUCLEAR MAGNETIC RESONANCE; Organic chemistry; ORGANIC COMPOUNDS; ORGANOMETALLIC COMPOUNDS; Physical Sciences; Preparations and properties; RARE EARTH COMPLEXES; RESONANCE; SAMARIUM COMPLEXES; Science & Technology; HYDROCARBYL; F-ELEMENT THERMOCHEMISTRY; RING-CLOSURE REACTIONS; HIGHLY REACTIVE ORGANOLANTHANIDES; COMPLEXES; CHEMISTRY; DISRUPTION ENTHALPIES; METAL; HYDROAMINATION CYCLIZATION; 2+2 CYCLOADDITIONS; Five membered ring; Catalytic reaction; Acetylenic compound; Aliphatic compound; Nitrogen heterocycle; Samarium Organic compounds; Metallocene; Regiospecificity; Cyclization; Six membered ring; Reaction mechanism; Primary amine; Seven membered ring
• ISSN: 0276-7333; 1520-6041
• DOI: 10.1021/om00014a015

The organolanthanide complex (eta5-Me5C5)2-SmCH(TMS)2 serves as a precatalyst for the efficient and regiospecific hydroamination/cyclization of aliphatic and aromatic aminoalkynes RC=C(CH2)nNH2 to yield the corresponding heterocycles RCH2C=N(CH2)n-1CH2. Kinetic and mechanistic evidence argues that the turnover-limiting step is intramolecular alkyne insertion into the Sm-N bond followed by rapid protonolysis of the resulting Sm-C bond.