Furan 2-nitro

Benzo[b]furan, 2-nitro-reduction, 4, 74, 647 Benzo[b]furan, 5-nitro-mass spectrometry, 4, 583 Benzo[b]furan, 2-(4-nitrophenyl)-properties, 4, 708 Benzo[b]furan, 2-phenyl-bromination, 4, 605 chloromethylation, 4, 607 nitration, 4, 604 photochemical reactions, 4, 636 properties, 4, 697 Benzo[b]furan, 3-phenyl-synthesis, 4, 697... 

Furan, 2-methyl-5-trifluoromethyl- H NMR, 4, 558 <68JHC95>, 558 <68JHC95> Furan, 2-nitro-... 

An alternative route to 5-nitro-2-furancarboxaldehyde requires nitration of 2-furancarboxaldehyde oxime [1121 -47-7] with mixed acid to give the nitrated oxime [555-15-7] and concomitant hydrolysis (22). Furthermore, 2-furan-carboxaldehyde derivatives with the R-substituent in place have been nitrated to the desired product (23). 

Z-Furan. 3-(5-Nitro-2-furanyl)-2-propenamide, is prepared by condensation of 5-nitro-2-furancarboxaldehyde diacetate with malonic ester followed by PCl chlorination and amination (29). The product was marketed in Japan as a food preservative. 

Nitrovin. 2- 3-(5-Nitro-2-furanyl)-l-[2-(5-nitro-2-furanyl)ethenyl]-2-propenyhdene hydrazinecarboximidamide hydrochloride has been marketed for both human and veterinary use as an antibacterial agent. The product, which has also seen use as a veterinary food additive (32), is prepared from 5-nitro-2-furan-carboxaldehyde and acetone followed by treatment of the resulting dione with aininoguariidine (33). 

NitrofuraZone. 2-[5-Nitro-2-furanyl)methylene]hydrazinecarboximide, the first nitrofiiran to be employed clinically, is prepared from 5-nitro-2-furancarboxaldehyde and semicarbazide (19). This product has seen clinical use topically as an antibacterial, for systemic appHcation for bacterial infections in poultry and swine, and also has been employed as a food additive. In rats, nitrofurazone is hydroxylated at the 4 position of the furan moiety (27). The involvement of nitrenium ions has also been postulated in the mechanism of action of nitrofurazone (38). 

The effect of substituents on the reactivity of heterocyclic nuclei is broadly similar to that on benzene. Thus mem-directing groups such as methoxycarbonyl and nitro are deactivating. The effects of strongly activating groups such as amino and hydroxy are difficult to assess since simple amino compounds are unstable and hydroxy compounds exist in an alternative tautomeric form. Comparison of the rates of formylation and trifiuoroacetylation of the parent heterocycle and its 2-methyl derivative indicate the following order of sensitivity to substituent effects furan > tellurophene > selenophene = thiophene... 

Mercury(II) acetate tends to mercurate all the free nuclear positions in pyrrole, furan and thiophene to give derivatives of type (74). The acetoxymercuration of thiophene has been estimated to proceed ca. 10 times faster than that of benzene. Mercuration of rings with deactivating substituents such as ethoxycarbonyl and nitro is still possible with this reagent, as shown by the formation of compounds (75) and (76). Mercury(II) chloride is a milder mercurating agent, as illustrated by the chloromercuration of thiophene to give either the 2- or 2,5-disubstituted product (Scheme 25). 

Benzo[c]furan, l,3-dihydro-6-nitro-l-phenyl- H NMR, 4. 574 <75JA5160>... 

UV. 4, 14 <71PMH(3)79), 588 (50JA753) Furan-2-carbaldehyde, trans-2-acetoxy-5-nitro-2,5-dihydro-, diacetate X-ray, 4, 549 (80T1817)... 

H NMR, 5, 558 <71BSF990) Furan-2-carbaldehyde, 4-methoxy- H NMR, 4, 558 <7IBSF990) Furan-2-carbaldehyde, 5-methyl- C NMR, 4, 565 (76AJCI07) Furan-2-carbaldehyde, 5-nitro-UV, 4, 588 <50JA753)... 

Furan-3-carboxamide, N,fV-dimethyl-AG, 4, 34 <76JOC3591, 77TI337) Furan-2-carboxylate, 2-nitro-, ethyl ester UV, 4, 588 <50JA753>... 

Furan, 2,5-bis(trimethylsilyloxy)-cycloaddition reactions, 4, 625 Diels-Alder reactions, 4, 77 synthesis, 1, 417 Furan, bromo-dipole moments, 4, 553 Furan, 2-bromo-electron diffraction, 4, 537 reactions, 4, 78 synthesis, 4, 604 Furan, 3-bromo-electron diffraction, 4, 537 Furan, 2-bromomethyl-5-nitro-reactions... 

Furan, 2,3-dihydro-5-methyl-polymers, 1, 276 Furan, 2,3-dihydro-3-methylene- H NMR, 4, 577 Furan, 2,5-dihydro-2-methylene- H NMR, 4, 577 tautomerism aromaticity and, 4, 595 Furan, 2,5-dihydro-2-nitro-structure, 4, 550 Furan, 2,3-dihydroxy-tautomerism, 4, 37 Furan, 2,4-dihydroxy-tautomerism, 4, 37 Furan, 3,4-dihydroxy-tautomerism, 4, 37 Furan, 2,5-diiodo-nitration, 4, 602 synthesis, 4, 712 Furan, 3,4-diiodo-reactions, 4, 650 Furan, 2,3-dimethoxy-synthesis, 4, 625, 648 Furan, 2,5-dimethoxy-synthesis, 4, 648 Furan, 3,4-dimethoxy-cycloaddition reactions, 4, 64, 625 lithiation, 4, 651 reactions... 

Furan-2-carbaldehyde, 5-methyl-synthesis, 4, 658 Furan-2-carbaldehyde, 5-nitro-as chemotherapeutic agent, 1, 179... 

Thieno[3,4-d][l,3]dithiol-2-one, 1-nitro-synthesis, 6, 1013 Thieno[3,4-c]furan, 4,6-dichloro-synthesis, 6, 1013 Thieno[3,4-c]furan, tetraphenyl-formation, 4, 1060 synthesis, 4, 1060 UV spectra, 4, 1044 Thieno[3,2-6]furans structure, 4, 1039 synthesis, 6, 1020 Thieno[3,4-c]furans... 

Furan-2-carboxylic acid reacts with sulfur tetrafluoride at 0 °C to give 2-furoyl fluoride, but attempts at further fluorination results in resin formation [222] A second carboxylic group and/or electron withdrawing substiments, such as the nitro or tnfluoromethyl group, stabilize the furan ring Thus, turandicar-... 

In a similar reaction, but with reversed polarities in the starting materials 3-nitrobenzofuran adds to l-phenyl-2-pyrrolidinoacetylene to afford a mixture of three components, one being 5-nitro-3-phenyl-2-pyrrolidino-l-benzoxepin (3, 27 %).183 In the first step of this reaction, a bond between C2 of the furan and the carbon atom in the a-position to the phenyl group is formed to produce a dipolar intermediate that can react in different directions. 

The reaction of 4-(l-cyclohexenyl)morpholine and ( )-(2-nitro-l-propenyl)benzene or (E)-3-(2-nitro-1-propenyl)furan gave almost exclusively the vyrc-adducts, as did the analogous reaction of l-(l-cyclohexenyl)piperidine13 14. 

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