Morpholinium Trifluoroacetate‐Catalyzed Aldol Condensation of Acetone with both Aromatic and Aliphatic Aldehydes

Abstract

We report a highly efficient, general and practical method for the aldol condensation of acetone with aromatic and aliphatic aldehydes, using morpholinium trifluoroacetate as a catalyst.

A Promiscuous De Novo Retro‐Aldolase Catalyzes Asymmetric Michael Additions via Schiff Base Intermediates

“…[3b] As et of unsaturated methyl ketones was therefore prepared and tested as potential Michael acceptor substrates (Supporting Information, Scheme S1). [9] Thek etones were expected to react with Lys83, the catalytic amine,t of orm ac ovalently bound iminium intermediate,w hich could be attacked by appropriate nucleophiles.Michael additions of 1a-1g with arange of donor molecules (2a-2e)w ere performed in the presence of RA95.5-8 and monitored by HPLC (see the Supporting Information for details). Although most combinations afforded only small amounts of the new products,the reaction of 1aand ethyl 2-cyanoacetate (2a)was particularly rapid and high-yielding (Scheme 1b).…”

One‐Pot Synthesis of 3‐Cyano‐2‐pyridones

“…To our delight, pyrrolidine ( 4c ) gave the desired 2‐pyridone ( 5 ) with 44% yield (entry 3). Aziridine ( 4a ) was found to be ineffective (entry 1), while treatment with azetidine ( 4b ), piperidine ( 4e ) , and morpholine ( 4f ) led to very low yields (entry 2, 5, and 6).…”

Selectivity Engineering in One Pot Synthesis of Raspberry Ketone: Crossed Aldol Condensation of p‐Hydroxybenzaldehyde and Acetone and Hydrogenation over Novel Ni/Zn‐La Mixed Oxide

“…Also, reusability study revealed 0.4 ppm leaching of Pd with some metal agglomeration over the support. Zumbansen et al [17] have used morpholinium trifluroacetate as a catalyst which is most likely to be an ionic liquid. The catalyst gave 80% yield of raspberry ketone after 12 h of reaction time.…”

“…At optimum conditions, the yield of raspberry ketone obtained after 5 h was 82.5%. Morpholinium trifluoroacetate, an ionic liquid like compound, was examined for the aldol condensation of aliphatic aldehyde such as p ‐hydroxybenzaldehyde and acetone . An attempt was made by Climent et al.…”

“…Morpholinium trifluoroacetate, an ionic liquid like compound, was examined for the aldol condensation of aliphatic aldehyde such as phydroxybenzaldehyde and acetone. [17] An attempt was made by Climent et al for one-pot synthesis of raspberry ketone through the Heck reaction of 4-methoxyiodobenzene and methyl vinyl ketone followed by hydrogenation of intermediate over a heterogeneous catalyst. Different supports were tested such as Al 2 O 3 , MgO, TiO 2 , hydrotalcite (HT) and hydroxyapatite (HA), among which Pd/TiO 2 gave the best performance for this reaction.…”