A convenient, versatile, and easy to handle intramolecular hydrofunctionalization of alkenes (C–O and C–N bonds formation) is reported using a novel niobium-based catalytic system. This atom economic and eco-friendly methodology provides an additional synthetic tool for the straightforward formation of valuable building blocks enabling molecular complexity. Various pyran, furan, pyrrolidine, piperidine
Intramolecular Hydroamination of Aminoalkenes by Calcium and Magnesium Complexes: A Synthetic and Mechanistic Study
作者:Mark R. Crimmin、Merle Arrowsmith、Anthony G. M. Barrett、Ian J. Casely、Michael S. Hill、Panayiotis A. Procopiou
DOI:10.1021/ja9003377
日期:2009.7.22
aminoalkenes. The reactions proceeded under mild conditions, allowing the synthesis of five-, six-, and seven-membered heterocyclic compounds. Qualitative assessment of these reactions revealed that the ease of catalytic turnover increases (i) for smaller ring sizes (5 > 6 > 7), (ii) substrates that benefit from favorable Thorpe-Ingold effects, and (iii) substrates that do not possess additional substitution
Switchable Stereoselectivity in Bromoaminocyclization of Olefins: Using Brønsted Acids of Anionic Chiral Cobalt(III) Complexes
作者:Hua-Jie Jiang、Kun Liu、Jie Yu、Ling Zhang、Liu-Zhu Gong
DOI:10.1002/anie.201705066
日期:2017.9.18
Brønsted acids of anionic chiral CoIII complexes act as bifunctional phase‐transfer catalysts to shuttle the substrates across the solvent interface and control stereoselectivity. The diastereomeric chiral CoIII‐templated Brønsted acids, with the same chiral ligands, enabled a switch in the enantioselective bromoaminocyclization of olefins to afford the two enantiomers of 2‐substituted pyrrolidines
Reverse Cope elimination reactions. 1. Mechanism and scope
作者:Engelbert Ciganek、John M. Read、Joseph C. Calabrese
DOI:10.1021/jo00123a013
日期:1995.9
N-4-Pentenyl- and N-5-hexenyl-N-methylhydroxylamine cyclized under mild conditions in a reverse Cope elimination reaction to give 1,2-dimethylpyrrolidine N-oxide and 1,2-dimethylpiperidine N-oxide, respectively. The reaction was shown to be concerted and thermodynamically controlled. The scope of this novel cyclization is discussed, and comparisons are made with the closely related and previously reported cyclization of monosubstituted alkenylhydroxylamines to give cyclic hydroxylamines.
Black,D.S.C.; Doyle,J.E., Australian Journal of Chemistry, 1978, vol. 31, p. 2247 - 2257