Synthesis of Cαα-unsymmetrically disubstituted nitroesters by electron transfer C-alkylation of ethyl 2-nitropropionate anion

Synthesis of α-Amino Esters via α-Nitro or α-Oxime Esters: A Review

“…53 Moreover, in DMSO, the same reaction was found to lead to benzaldehyde along with ethyl 2-(hydroxyimino)propanoate (32) resulting from O-benzylation. 54 Also of note is the electrophilic trifluoromethylation of substituted α-nitro esters such as 26b (R = Et, R′ = Ph) which gave the quaternary nitro ester 33 (R′ = Ph) in 59% yield. 55 The preparation of many other α,α-disubstituted nitro esters 34a,b from the reaction between ethyl 2-nitropropanoate (26b, R = Et, R′ = H) and a variety of electrophiles has been reviewed.…”

“…55 The preparation of many other α,α-disubstituted nitro esters 34a,b from the reaction between ethyl 2-nitropropanoate (26b, R = Et, R′ = H) and a variety of electrophiles has been reviewed. 54 For instance, the aldol reaction of 26b (R = Et, R′ = H) with aqueous formaldehyde proceeds in excellent yield to give compound 34b (R = Et) when catalyzed by triphenylphosphine, sodium hydroxide, or potassium phosphate. 56 Moreover, a high degree of enantioselectivity for this type of reaction was achieved when starting from imines and using a bifunctional catalyst 57 or from formaldehyde when using an asymmetric phase-transfer catalyst, 56b especially when starting from a hindered benzyl ester.…”

“…91 Across the years, this approach was then used frequently. 54,92 A report from 1977 described the use of a quaternaryammonium-based polymer-supported nitrite anion to prepare ethyl 2-nitropropanoate (58, R = Me) from ethyl 2-bromopropanoate (60, R = Me) in 95% yield. 93 The use of tetraalkylammonium nitrites along with various types of alkyl nitrites scavengers was also investigated.…”

Strategies in Synthetic Radical Organic Chemistry. Recent Advances on Cyclization and SRN1 Reactions

“…The reaction of p-nitrobenzyl chloride 79 with the anion of ethyl 2-nitropropionate, has recently been used to synthesize the corresponding α-amino acid by reduction of the substitution product (eq. 70) [149].…”

Aberrant SRN1 Reaction of 4-Aminophenol with α,p-Dinitrocumene: EPR Observation of Intermediates

“…Interest in the scope of electron transfer induced nucleophilic substitutions and in the factors controlling them has intensified recently due to imaginative exploitations of inter- and intramolecular versions of this reaction in new synthetic procedures. 1a-f The substitution of NO 2 in α, p -dinitrocumene [2-nitro-2-(4-nitrophenyl)propane 1 ] by sundry nucleophiles is regarded as a representative S RN 1 process. , Kornblum and co-workers studied the reaction of 1 with carbon-centered nucleophiles, thiolate, CN - , N 3 - , amines, and 1-methyl-2-naphtholate anion some time ago. , According to the orthodox S RN 1 mechanism the process is initiated by electron transfer to 1 , followed by rapid and irreversible decomposition of the resulting radical anion 2 to give the 4-nitrocumyl radical ( 3 ) and nitrite ion. The key step is coupling of a nucleophile (ArO - ) with 3 to produce the radical anion of the substitution product ( 4 ).…”