Subscribe to RSS
A Simple and Highly Diastereoselective One-Pot Synthesis of Mannich-Bases
31 December 2000 (online)
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.
β-amino ketones - diastereoselective aminoalkylation - enamines - imines - iminium salts