Polyethyleneglycol an efficient solvent for stereoselective synthesis of β-amino ketones via direct Mannich reaction

Abstract

Polyethyleneglycol-2,4,6-Trichloro-1,3,5-Triazine (PEG 400-TCT) promotes a series of three component one-pot reactions of cyclohexanones with aromatic aldehydes and aniline. β-amino ketones are afforded in high yields and high stereoselectivity, in favor of the anti-isomer. Four new compounds are reported.

Multicomponent reactions in unconventional solvents: state of the art

“…280 Mannich-type three-component one-pot reactions of cyclohexanones, aromatic aldehydes and aniline could be performed in PEG-400 in conjunction with 2,4,6-trichloro-1,3,5triazine as catalyst. 281 Lei and Hu 282 observed that a Biginellilike three-component condensation reaction of aromatic aldehyde, β-dicarbonyl compound and 2-aminobenzimidazole could be performed in water by using thiamine hydrochloride (VB 1 ), which is a nonflammable, inexpensive, and non-toxic reagent, as catalyst (Scheme 77). This method offers a straightforward and eco-friendly method for synthesizing benzo [4,5]imidazo[1,2-a]pyrimidine derivatives 134.…”

Recent progress in the chemistry of β-aminoketones

“…Thus, one-pot three-component reactions of aryl or cycloalkyl ketones with aryl aldehydes and aryl amines in ethanol at room temperature under catalytic conditions yielded the respective β-aminoketones 14a–q (Scheme 7). 85–92 The sequence of these reactions is related to Mannich-type reactions in a green protocol. The nanocatalyst activated the aldehyde ketone to nucleophilic attack by the amine group, and consequently enabled the enolization of the aryl or cycloalkyl ketones in the condensation.…”