A study on the synthesis of β-amino acids: the first synthesis of a bicyclic hemiaminal (3,3-dimethyl-1-(2,4,5-trifluorophenyl) tetrahydro-3H,5H-oxazolo[3,4-c] [1,3] oxazin-5-one)

Abstract

We synthesized (4S)-4-(2-((tert-butyldimethylsilyl)oxy)ethyl)-5-(2,4,5-trifluorophenyl) oxazolidin-2-one and examined its Pd/C-catalyzed hydrogenation reaction. The condensation and rearrangement reaction of acetone with (4S)-4-(2-((tert-butyl dimethylsilyl)oxy)ethyl)-5-(2,4,5-trifluorophenyl)oxazolidin-2-one resulted in the formation of a hemiaminal structure containing a fused oxazine-oxazole ring, whose exact configuration was determined by X-ray crystal analysis. A mechanism was proposed to explain the formation of the fused oxazine-oxazole ring, which has a hemiaminal structure.

Green catalytic synthesis of symmetric and non-symmetric β-hydroxy-1,2,3-triazoles by using epichlorohydrin in the presence of Cu(ii) coordination compounds containing oxazole ligands

“…17 The copper coordination compounds with oxazole ligands showed high catalytic activity in oxidation reactions 18 and also in the synthesis of 1,2,3,-triazoles. 19 Two connected oxazole rings, known as oxazolo[3,4- c ]oxazole compounds (see Scheme 1b), 20 can be synthesized by the reaction of amino-alcohols containing two alcoholic functionalities with two molar ratios of aldehydes or ketones. Although a relatively high number of oxazole ligands and their copper coordination compounds have been reported, 21 searching the literature including the Cambridge Crystallographic Data Center (CCDC) 22 indicates that there are only four reports on coordination compounds with bis-oxazole ligands.…”