79865-85-3Relevant academic research and scientific papers
A Simple and Highly Diastereoselective One-Pot Synthesis of Mannich-Bases
Arend, Michael,Risch, Nikolaus
, p. 974 - 976 (2007/10/03)
A convenient one-pot procedure for the synthesis of β-amino ketones 5 from economical shelf reagents is described. Iminium salts 3 are generated in virtually quantitative yields from secondary amines 1 and aldehydes 2 mediated by NaI/Me3SiCl/NEt3. Subsequently, the salts 3 are used for the in situ aminoalkylation of enamines 4. The method provides the Mannich bases 5 in high yields and excellent diastereoselectivities (>96 % ds). It can also be applied for the aminoalkylation of other nucleophiles such as imines or electron-rich aromatic compounds.
ACTIVATING ACTION OF THE IMMONIUM GROUP IN THE SUBSTITUTION OF ALKOXYL AND HALOGEN ATOMS BY THE ALKYLAMINO GROUP IN THE BENZENE RING
Yudin, L. G.,Blokhin, A. V.,Bundel', Yu. G.,Simkin, B. Ya.,Terenin, V. I.
, p. 2064 - 2068 (2007/10/02)
The substitution of the alkoxy group in o-, p-, and m-alkoxybenzylidenedimethylimmonium iodides by the action of aliphatic amines was investigated.Only p-alkoxy derivatives enter into the reaction forming, after hydrolysis, p-alkyl- and p-dialkylaminobenzaldehydes.Substitution can also be realized in p-alkoxybenzaldehydes and Schiff bases in the presence of the amine hydrochloride.Similarly, the halogen atom in p-halogenobenzaldehydes is substituted by the aliphatic amine residue.Quantum-mechanical calculations of the energy of anionic localization and charge at the attacked carbon atom o f the benzene ring are consistent with the experimantal data.
