Hf(OTf)4 as a Highly Potent Catalyst for the Synthesis of Mannich Bases under Solvent-Free Conditions
作者:Shuai-Bo Han、Jing-Ying Wei、Xiao-Chong Peng、Rong Liu、Shan-Shan Gong、Qi Sun
DOI:10.3390/molecules25020388
日期:——
Hf(OTf)4 was identified as a highly potent catalyst (0.1–0.5 mol%) for three-component Mannich reactionunder solvent-free conditions. Hf(OTf)4-catalyzed Mannich reaction exhibited excellent regioselectivity and diastereoselectivity when alkyl ketones were employed as substrates. 1H NMR tracing of the H/D exchange reaction of ketones in MeOH-d4 indicated that Hf(OTf)4 could significantly promote the
Stereoselective Synthesis of β-Amino Ketones via Direct Mannich-Type Reactions, Catalyzed with ZrOCl2·8H2O under Solvent-Free Conditions
作者:Bagher Eftekhari-Sis、Amir Abdollahifar、Mohammed M. Hashemi、Maryam Zirak
DOI:10.1002/ejoc.200600493
日期:2006.11
zirconium oxychloride (ZrOCl2·8H2O) efficiently catalyzes the directMannich-typereaction of a variety of in situ generated aldimines using aldehydes and anilines with ketones in a three-componentreaction under solvent-free conditions. The reaction proceeds rapidly and affords the corresponding β-aminoketones in good to high yields with good to excellent stereoselectivities. The catalyst can be recycled
Catalytic stereoselective Mannich reaction under solvent-free conditions
作者:Najmadin Azizi、Roya Baghi、Elham Batebi、Seyed Mohammad Bolourtchian
DOI:10.1016/j.crci.2011.10.011
日期:2012.4
Résumé Silicon tetrachloride catalyzed one-pot three-component Mannich reaction of cyclic ketones, aromatic aldehydes, and aromatic amine under solvent-free conditions affords the corresponding β-amino ketones with excellent yield and good to excellent anti-selectivity.
afforded corresponding Mannich adducts. In the case of cyclohexanone, stereoselectivity was changed depending on the nature of the substitution on benzaldehydes, in which, moderate electron-donating and electron-withdrawing groups afforded the anti isomer as major products, but strongly electron-donating substituted benzaldehydes led to syn isomer as the major Mannich adducts. Mannich reaction with cycloheptanone
Squaric acid catalyzedthree-component Mannich reaction of aromatic aldehydes, aromatic amines and cyclic ketones in water and solvent-free conditions at room temperature. This protocol has several advantages such as good yields, mild conditions, novel organocatalyst, and good anti selectivities.Graphical AbstractSquaric acid catalyzedthree-component Mannich reaction of aromatic aldehydes, aromatic