59862-74-7

Upstream product

• 555-16-8 4-nitrobenzaldehdye 
• 75-31-0 isopropylamine 
• 38681-76-4 N-isopropyl-4-nitrobenzamide 

Downstream Products

• 117617-26-2 (4S,5S)-4-(4-Nitro-phenyl)-2-oxy-4,5-dihydro-isoxazole-3,5-dicarboxylic acid diethyl ester 
• 60826-14-4 (4S,5S)-4-(4-Nitro-phenyl)-2-oxy-4,5-dihydro-isoxazole-3,5-dicarboxylic acid dimethyl ester 
• 20378-54-5 (E)-2-isopropyl-3-p-nitrophenyloxaziridine 

Relevant academic research and scientific papers

Tf2O-TMDS combination for the direct reductive transformation of secondary amides to aldimines, aldehydes, and/or amines

The direct partial reduction of highly stable secondary amides to more reactive aldimines and aldehydes is a challenging yet highly demanding transformation. In this context, only three methods have been reported. We report herein an improved version of the Charette’s method. Our protocol consists of activation of secondary amides with triflic anhydride/2-fluoropyridine, and partial reduction of the resulting intermediates with 1,1,3,3-tetramethyldisiloxane (TMDS), which delivered aldimines or aldehydes upon acidic hydrolysis. Aromatic amides were reduced to the corresponding aldimines in 85%–100% NMR yields, and yields (NMR) from aliphatic amides were 72%–86%. Acidic hydrolysis of the aldimine intermediates afforded, in one-pot, the corresponding aldehydes in 80%–96% yields. A simple protocol was established to isolate labile aldimines in pure form in 92%–96% yields. The improved method gave generally higher yields as compared to the known ones, and features the use of cheaper and more atom-economical TMDS as a chemoselective reducing agent. In addition, a convenient extraction protocol has been established to allow the isolation of amines, which constitutes a mild method for the N-deacylation of amides, another highly desirable transformation. The extended method retains the advantages of the original method of Charette in terms of mild conditions, good functional group tolerance, and excellent chemoselectivity.

A Convenient One-Pot Synthesis of 4-Substituted 3,5-Bis(alkoxycarbonyl)-4,5-dihydroisoxazole 2-Oxides from Aldehydes and Nitroacetic Esters in a Solid-Liquid Reaction System and Subsequent Deoxygenation

4-Substituted 3,5-bis(alkoxycarbonyl)-4,5-dihydroisoxazole 2-oxides are obtained from nitroacetic esters and imines which are prepared from aldehydes and isopropylamine in the presence of molecular sieves.Reduction of the N-oxides with trimethyl phosphite