A One-Flask Synthesis of Weinreb Amides from Chiral and Achiral Carboxylic Acids Using the Deoxo-Fluor Fluorinating Reagent was written by Tunoori, Ashok Rao;White, Jonathan M.;Georg, Gunda I.. And the article was included in Organic Letters in 2000.Reference of 87694-53-9 This article mentions the following:
The reagent [bis(2-methoxyethyl)amino]sulfur trifluoride (Deoxo-Fluor reagent) converts carboxylic acids to the corresponding acid fluorides, which then react with N,O-dimethylhydroxylamine to give the corresponding Weinreb amides in high yields. The reaction proceeds without racemization when optically active acids are used as the starting material. This method is operationally simple and provides the products in high purity. Thus, N,N-diisopropylethylamine was added to a suspension of N,O-dimethylhydroxylamine hydrochloride in dichloromethane to give the free base N,O-dimethylhydroxylamine. Treatment of trans-crotonic acid with Deoxo-Fluor reagent resulted in the formation of the intermediate acid fluoride, which upon addition of N,O-dimethylhydroxylamine gave the desired N-methoxy-N-Me-trans-crotonamide [(2E)-N-methoxy-N-methyl-2-butenamide]. Similar treatment of N-BOC-
(S)-tert-Butyl (1-(methoxy(methyl)amino)-1-oxo-3-phenylpropan-2-yl)carbamate (cas: 87694-53-9) belongs to esters. Volatile esters with characteristic odours are used in synthetic flavours, perfumes, and cosmetics. Certain volatile esters are used as solvents for lacquers, paints, and varnishes. Because of their lack of hydrogen-bond-donating ability, esters do not self-associate. Consequently, esters are more volatile than carboxylic acids of similar molecular weight.Reference of 87694-53-9
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