3-Nitroacrylic acid

Acrylic acid and derivs 1 A96-A97 acrylic acid-trinitrophenylester 1 A97 acrylic esters, monomeric 1 A97 acrylic resins and plastics 1 A97 acryloylazide 1 A97 3-nitroacrylic acid 1 A97... 

The reduction of derivatives of a-nitroacrylic acid to amino acids follows a similar route the amine seems for a-nitro carboxylic acids to be formed partly through the oxime and partly, at a more negative potential, through another intermediate [33]. 

J-Unsaturated nitro compounds, suchasa-nitrostilbene172 and 3,4-dinitro-3-hexene,173 add alcohols in the presence of bases. 2-Nitroacrylic acid and methanol give 2-methoxy-3-nitropropionic acid without requiring addition of a catalyst.63... 

This procedure for the synthesis of ethyl 3-nitroacrylate is essentially that of Stevens and Emmons.2 Four major changes have been introduced by the submitters rapid introduction of dinitrogen tetroxide no purification of the intermediate nitro iodo ester use of dry, finely powdered sodium acetate for elimination of hydroiodic acid and percolation of the final product through a mat of alumina. With these modifications, the preparation is reproducible and highly efficient (80-90% overall). 

Martin NJA, Cheng X, List B (2008) Organocatalytic asymmetric transferhydrogenation of heta-nitroacrylates accessing beta(2)-amino acids. J Am Chem Soc 130 13862-13863... 

Reduction of 3-nitroacrylates 43 by Saccharomyces carlshergensis Old Yellow Enzyme is the key step in the synthesis of optically pure P-2-amino acids (Scheme 2.18). High yields and enantioselectivities of the initially derived nitro-compounds 44 were achieved. The latter can be further chemically elaborated to the corresponding P-amino acids 45 [20]. 

Racemic analogs of showdomycin have been synthesized from adducts (352 and 353) of methyl 2-nitroacrylate with furan. Synthesis of DL-2-ept-showdomycin involved treatment of the adducts with m-chloroperoxybenzoic acid, followed by nitrous acid elimination, to give the alkenic epoxide 379. Opening of the oxirane ring, and a sub-... 

Nitro-4H-pyrimido[2,l-a]isoquinolin-4-one (241) was obtained via 240 in 68% yield when 1-aminoquinoline and ethyl 3-ethoxy-2-nitroacrylate were reacted in ethanol for 2 h at ambient temperature, and then the reaction mixture was evaporated in vacuo to dryness and the residue was cy-clized in polyphosphoric acid at 95°C for 50 min (77CB2480). 

Nitro-4//-pyrido[l,2-a]pyrimidin-4-ones 176 were prepared by the cy-clization of 6-unsubstituted 3-(2-pyridylamino)-2-nitroacrylates 175 (R1 = H) in polyphosphoric acid at 120°C for 1.5 hours in 50-63% yields [90JCR(S)308]. Instead of cyclizing, the 6-substituted derivatives 175 (R1 H) decomposed under these conditions. 

The a-addition of alkyl or aryl thionucleophiles R H to y9-nitroacrylates R2(NC>2) C=CC02R3 in THF in the presence of Et3N or DBU does not stop at y9-nitro-o -thioalkanoates R2CH(N02)CH(SR1)C02R3, but proceeds further with concomitant elimination of nitrous acid to afford a-thioacrylates R2CH=C(SR1)C02R3.191... 

Cycloalkanone enamines react with ethyl / -nitroacrylate to form adducts which yield y-lactones on treatment with sodium borohydride. Base-induced elimination of the elements of nitrous acid gives oe-methylenebutyrolactones 23 (equation 16)35. 

Ethyl 3-ethoxy-a-nitroacrylate with 1,1-diphenylhydrazine in ethanol followed by heating has been shown to give l,4-bis(diphenylamino)-2,5-diethoxycarbonyl-l,4-dihydropyrazine (1586). A small amount of 2,5-dicyano-l,4-bis(dimethylamino)-1,4-dihydropyrazine was obtained from the reaction of 2-chloro-3-(2, 2-dimethyl-hydrazino)propionitrile [(Me)2NNHCH2CH(Cl)CN] with sodium hydride (1587). Hexaalkyl-l,4-dihydropyrazines and other 1,4-dialkyl-1,4-dihydropyrazines can be obtained by thermolysis of the products of reaction of a-(alkylamino)carboxylic acid esters with alkylmagnesium bromide. Thus the reaction of ethyl a-s-butyl-aminopropionate with ethylmapesium bromide, followed by heating in vacuo to 250-300°, gave 2,5-dimethyl-3,6-diethyl-l,4-di-s-butyl-l,4-dihydropyrazine (1588). 

Yoshida developed an enantioselective Michael addition reaction of a-branched aldehydes to p-nitroacrylates by using a primary a-amino acid, L-phenylalanine (Phe-OH), lithium salt 14 (Scheme 2.9). The obtained p-formyl-p -nitroesters were transformed into the corresponding cyclic amino acids in high yields via hydrogenolysis on Pd/C. 

SCHEME 14.12. Conjugate sulfa-Michael addition to a-substituted (3-nitroacrylates promoted by thiourea 12 and further transformation into a-thio-p -amino acids. 

The sulfa-Michael reaction to a (3,(3-disubstituted Michael acceptor, affording adducts with a new quaternary stereocenter, is usually challenging, mainly due to the low reactivity and reversibility of the process. Xiao and co-workers [41] reported that thiourea 12 promoted the highly enantioselective conjugate addition of arenethiols and substituted benzyl thiols to a-substituted (3-nitroacrylates. The enantioenriched adducts could be easily transformed into a-thio-(P -amino acids, valuable building blocks for the synthesis of p- or mixed p/a-peptides (Scheme 14.12). 

V. Gutnov, A. Pd-catalyzed Asymmetric Conjugate Addition of Arylboronic Acids to 2-nitroacrylates A Facile Route to p2-homophenylglycines. Tetrahedron Lett. 2014, 55, 267-270. 

The powerful activation provided by the nitro group can even be enhanced by the presence of an additional EWG, such as an ester moiety. Accordingly, the bioreduction of ethyl (3-nitroacrylates such as 84 proceeded very efficiently with OYEl affording the optically enriched saturated (J )-nitroesters, which were employed to prepare (3 -amino acids, for example R)-86, challenging synthetic targets of undiscussed relevance in both chemistry and biology (Scheme 3.24, see Chapter 13 for further details) [105]. 

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