4209-68-1Relevant articles and documents
Hydrogen-Borrowing Amination of Secondary Alcohols Promoted by a (Cyclopentadienone)iron Complex
Aiolfi, Francesco,Bai, Xishan,Cettolin, Mattia,Dal Corso, Alberto,Gennari, Cesare,Piarulli, Umberto,Pignataro, Luca
, p. 3545 - 3555 (2019/09/09)
Thanks to a highly active catalyst, the scope of the (cyclopentadienone)iron complex-promoted 'hydrogen-borrowing' (HB) amination has been expanded to secondary alcohols, which had previously been reported to react only in the presence of large amounts of co-catalysts. A range of cyclic and acyclic secondary alcohols were reacted with aromatic and aliphatic amines giving fair to excellent yields of the substitution products. The catalyst was also able to promote the cyclization of diols bearing a secondary alcohol group with primary amines to generate saturated N-heterocycles.
Highly efficient, base-catalysed, intramolecular hydroamination of non-activated olefins
Quinet, Coralie,Jourdain, Pierre,Hermans, Christophe,Ates, Ali,Lucas, Isabelle,Markó, István E.
, p. 1077 - 1087 (2008/09/17)
The intramolecular hydroamination of a large variety of non-activated alkenes can be efficiently catalysed by small amounts of lithium bases, providing smoothly and in high yields the corresponding five- and six-membered ring heterocycles. Fused and bridged bicyclic amines, of varying ring sizes, can be readily prepared either by a sequential hydroamination process or by a tandem, double addition reaction.
Cp*Ir complex-catalyzed N-heterocyclization of primary amines with diols: A new catalytic system for environmentally benign synthesis of cyclic amines
Fujita, Ken-Ichi,Fujii, Takeshi,Yamaguchi, Ryohei
, p. 3525 - 3528 (2007/10/03)
(Chemical Equation Presented) A new efficient method for the N-heterocyclization of primary amines with diols catalyzed by a Cp*Ir complex was developed. A variety of five-, six-, and seven-membered cyclic amines were synthesized in good to excellent yields with the formation of only water as a byproduct. A two-step asymmetric synthesis of (S)-2-phenylpiperidine was also achieved using (R)-1-phenylethylamine as a starting primary amine.
DIASTEREOSELECTIVE ELECTROCHEMICAL REDUCTIVE AMINATION OF 2,5-HEXANEDIONE AND 2,6-HEPTANEDIONE
Concialini, Vittorio,Roffia, Sergio,Savoia, Diego
, p. 77 - 82 (2007/10/02)
The electrochemical reductive amination of 2,5-hexanedione with ammonia and 1-phenylethylamine at the mercury cathode afforded the corresponding 2,5-dimethylpyrrolidines with satisfactory yield and excellent cis-selectivity (90-98percent), but with arylamines mixtures of pyrroles and diastereoisomeric pyrrolidines were obtained.Only pyrroles were obtained with methyl- and benzylamine.On the other hand, 2,6-dimethylpiperidine (98percent cis) was obtained in low yield from 2,6-heptanedione and ammonia.The stereochemical outcome, along with the observation of a single reduction peak for the overall four-electron reduction, is consistent with a mechanism involving reduction of iminium ions, where the diastereoselctivity is controlled in the protonation of cyclic α-aminoalkyl radicals at the radical carbon atom.However, an alternative mechanism, involving the reduction of radicals to the corresponding carbanions followed by fast protonation, although less probable, could not be discarded.
Diastereoselective synthesis of 2,5-dimethylpyrrolidines and 2,6- dimethylpiperidines by reductive amination of 2,5-hexanedione and 2,6- heptanedione with hydride reagents
Boga,Manescalchi,Savoia
, p. 4709 - 4722 (2007/10/02)
The reductive amination of 2,5-hexanedione and 2,6-heptanedione with ammonia and primary amines in the presence of hydride reagents afforded 2,5- dimethylpyrrolidines and 2,6-dimethylpiperidines with variable diastereoselectivity, as the cis/trans ratio was affected by the size of the ring formed and the steric and electronic properties of the nitrogen substituent. Increasing the bulkiness of the nitrogen substituent, the cis pyrrolidines and the trans-piperidines were obtained with enhanced selectivity.
Catalytic Hydrogenation of Pyrroles at Atmospheric Pressure
Kaiser, Hans-Peter,Muchowski, Joseph M.
, p. 4203 - 4209 (2007/10/02)
N-(tert-Butoxycarbonyl)pyrroles are catalytically hydrogenated to the corresponding pyrrolidines, over 5percent platinum on carbon catalyst, at room temperature and atmospheric pressure.Under these conditions O-benzyl groups are retained and 2,5-disubstit
