Stereoselective Synthesis of β‐Amino Ketones via Direct Mannich‐Type Reactions, Catalyzed with ZrOCl₂·8H₂O under Solvent‐Free Conditions

Abstract

At room temperature, zirconium oxychloride (ZrOCl 2 ·8H 2 O) efficiently catalyzes the direct Mannich-type reaction of a variety of in situ generated aldimines using aldehydes and anilines with ketones in a three-component reaction under solvent-free conditions. The reaction proceeds rapidly and affords the corresponding β-amino ketones in good to high

Synthesis and structure of an air-stable organoantimony complex and its use as a catalyst for direct diastereoselective Mannich reactions in water

“…In the present investigation, the aldehydes with electron-withdrawing groups ( Table 3, entries 4 and 5) show slightly higher reaction activity than the aldehydes with electron-donating groups ( Table 3, entries 2 and 3). The reaction of octanal, aniline, and cyclohexanone produces the corresponding b-amino ketone in 50% yield even in prolonged reaction time (8 h), similar to that reported by Eftekhari-Sis et al [44]. Other aromatic amines such as o-toluidine was also tested ( Table 3, entry 6), and good result was obtained.…”

Bromodimethylsulfonium Bromide Catalyzed Three‐Component Mannich‐Type Reactions

“…A similar diastereoselectivity was also observed by Hashemi and his group. [10] The anti/syn ratios were determined by 1 H NMR spectroscopy. To confirm the anti configurations of these products unambiguously, compound 5b was recrystallised from ethanol and a single-crystal XRD was performed.…”

“…Recently, directtype Mannich reactions of aldehydes, enolizable ketones or diethyl malonate, and arylamines in the presence of various catalysts such as NbCl 5 , [5] Zn(OTf) 2 , [6] silica sulfuric acid, [7] Yb(OPf) 3 , [8] [NaBAr F 4 ], [9] ZrOCl 2 ·8H 2 O, [10] etc. have been reported.…”

Nano-Rb2HPW12O40 as an Efficient and Novel Catalyst for One-Pot Synthesis of β-Amino Ketones

“…The syn/anti ratio was determined by 1 H NMR spectroscopy and by comparing our data with that of known compounds reported in the literature, 23,24 by using the coupling constants of the vicinal protons adjacent to C=O and NH. In general, the coupling constant of the anti isomer is higher than that of the syn isomer.…”