126191-13-7Relevant academic research and scientific papers
1-Benzotriazol-1-yl-3,3,3-trifluoro-2-methoxy-2-phenylpropan-1-ones: Mosher-Bt reagents
Katritzky, Alan R.,Mohapatra, Prabhu P.,Fedoseyenko, Dmytro,Duncton, Matthew,Steel, Peter J.
, p. 4268 - 4271 (2008/02/05)
(Chemical Equation Presented) Benzotriazole derivatives of 3,3,3-trifluoro-2-methoxy-2-phenylpropionic acid react with water-soluble amino acids and peptides in an acetonitrile/water (2:1) mixture to give the corresponding amides in quantitative yield.
The synthesis of some chiral 2-aminoalkyloxazole-4-carboxylates from isoxazol-5(2H)-ones
Cox, Matthew,Prager, Rolf H.,Svensson, Carina E.
, p. 887 - 896 (2007/10/03)
Ethyl 4-methyl-5-oxo-2,5-dihydroisoxazole-3-carboxylate can be N-acylated by a number of natural and synthetic phthalimidylamino acids in the presence of carbodiimides. The N-acyiated products form the corresponding oxazoles smoothly when irradiated at 300 nm in acetone. Removal of the phthalimido protecting group then gives 2-aminoalkyloxazole-4-carboxylate esters in good overall yields, and without significant racemization at any step.
The asymmetric synthesis of α-amino acids. Electrophilic azidation of chiral imide enolates, a practical approach to the synthesis of (R)- and (S)-α-azido carboxylic acids
Evans, David A.,Britton, Thomas C.,Ellman, Jonathan A.,Dorow, Roberta L.
, p. 4011 - 4030 (2007/10/02)
Two complementary approaches to the asymmetric synthesis of α-amino acids have been achieved. In the initially investigated reaction sequence, the diastereoselective bromination of the illustrated boron enolate with N-bromosuccinimide was followed by stereospecific azide displacement by tetramethylguanidinium azide. The resulting α-azido carboximides may be readily purified to high diastereomeric purity by chromatography on silica. equation presented In the second reaction sequence, the illustrated potassium enolate was treated with 2,4,6-triisopropylbenzenesulfonyl azide, and the intermediate sulfonyl triazene was decomposed through an acetic acid quench to give the α-azido carboximide. The diastereoselection of the reaction as a function of R is as follows: R = Me, CH2Ph, 97:3; R = CHMe2, 98:2; R = CMe3, >99:1; R = Ph, 91:9. The important parameters of this azidation process were evaluated, and experiments were conducted to help elucidate the mechanism of the reaction. equation presented The α-azido carboximide products have been shown to be versatile α-amino acid synthons that may be readily converted to α-amino acids as well as to N-protected α-amino acid derivatives. The racemization-free removal of the chiral auxiliary was achieved in high yield both by saponification and transesterification, either before or after reduction and acylation of the azide functionality.
ASYMMETRIC HALOGENATION OF CHIRAL IMIDE ENOLATES. A GENERAL APPROACH TO THE SYNTHESIS OF ENANTIOMERICALLY PURE α-AMINO ACIDS.
Evans, David A.,Ellman, Jon A.,Dorow, Roberta L.
, p. 1123 - 1126 (2007/10/02)
The chiral N-acyl oxazolidones 2, as the derived dibutyl boron enolates, have been demonstrated to undergo diastereoselective bromination and subsequent azide displacement to give the α-azido carboximides 4a (5 cases).These adducts may be hydrolyzed under mild conditions to the enantiomerically pure α-azido carboxylic acids 5a.
