Nitro benzoic acid

Bromination. Gancm et al1 have used 1 for hromination of 4-mcthyl-3-nitro-benzoic acid (2). 

Nitro and Other Derivatives of Benzoic Acid Mononitrobenzoic AcidfMNBAc), 02N.C6H4.CO-OH mw 167.12, N 8.38%, OB to C02-ll9.7%. Three isomers are described in the literature 2-Nitrobenzoic Acid, col ndls(from w), mp 144 -8° Q 730-735kcal/mol(Refs 1 6) 3-Nitro-benzoic Acid, monoclinic yel prisms, mp 140-1° Q 729kcal/mol(Refs 2 5) Nishi Toki(Ref 4) investigated a number of methods of its prepn from benzaldehyde and noted that reaction with nitric -sulfuric acid mixts above 100° led to explosions 4-Nitrobenzoic Acid, lfts(from boiling w), mp 238 -40° QP 728kcal/mol(Ref 3)... 

It yel lfts, mp expl violently on heating or impact almost insol in cold ale can be obtd by treating cold 3-nitro-4-aminobenzoic acid with abs ale saturated with nitrous acid. The compd, in boiling ale, gives 3 nitro-benzoic acid Refs l)Beil 16,550 2)H.Salkowski,Ann 173,63 (1874)... 

Anhydro-2-Hydroxymf.rcuri-3-Nitro-benzoic Acid, 7, r, 12... 

The product from Step 6 was suspended in 4 ml DMF, treated with 4-bromomethyl-3-nitro benzoic acid (2.2 mmol), hydroxybenzotriazole (2.3 mmol) and 1ml diisopropylcarbodi-imide dissolved in 6 ml DMF. The suspension was shaken overnight, drained, washed as in Step 5, and the product isolated. 

The substrate 8 is synthesized in three steps from 4-chloro-3-nitro-benzoic acid (35)/... 

After isolation, 37 is used in the third step in an Sn2 reaction by triphenyl phosphine and forms alkyl triphenyl phosphonium salt 12 (Segment C), which is synthesized in an overall yield of 16 % starting from 4-chloro-3-nitro-benzoic acid (35). 

The longest linear sequence involves 22 steps and includes the construction of Segment C, its combination with Segment B, the introduction of Segment A, and the completion of the target compound. This chapter discusses 19 of these steps. The published synthesis of Segment C starts with 4-chloro-3-nitro-benzoic acid 22. The overall yield for this linear sequence is 0.9 %. 

A recently reported synthesis sequence [152] starts from MeOPEG-bound 4-fluoro-3-nitro-benzoic acid. After the nucleophilic aromatic substitution of the fluorine with piperazine, homopiperazine and 4-aminomethyl-piperidine (only the secondary amino group reacted) the remaining free amino function was acylated or sulfonated. 

Prisms from EtOH. M.p. 62°. Sol. CHClg, CgHg, hot EtOH. Spar. sol. EtiO. Very spar, sol. ligroin. KMnOg —> 6 - otuoro 3 nitro-benzoic acid. 

Cl]2> (Sy or (/ )-Cl,MeO-BIPHEP, 4-chloro-3-nitro-benzoic acid, and allyl acetate as a highly efficient and selective system for diol C-allylation [76], Under these conditions, diol Ih is converted to the homoallylic alcohol 2h in 79% isolated yield as a single diastereomer, as determined by NMR analysis of the crude reaction mixture (Scheme 7). 

ZS-(4-Chlorobenzoyl) peroxide 2V-(ot-Chlorobenzylidene)phenyl-hydrazine (pts) 4-Chloro-5-chlorosulfonyl benzoic acid 4-Chloro-5-chlorosulfonyl-3-nitro-benzoic acid p-Chloro-m-cresol (PCMC) (cu)... 

In order to investigate the further application of immobilized 4-fluoro-3-nitro benzoic acid synthon, we expanded our methodology to prepare 1,2-disubstituted benzimidazoles 23-25. Figure 11 shows our detailed efforts toward the preparation of a benzimidazole library. To achieve this goal, one pot cyclization of PEG-bound diamine 12 with trimethylorthoformate in TEA/... 

In order to demonstrate the versatility of the immobilized 4-fluoro-3-nitro benzoic acid scaffold 10, we also synthesized benzopiperazinones derivatives. The building block used for the synthesis of benzopiperazinones is shown in Fig. 14. Complete acylation of 12 at the secondary aniline site was achieved by a reaction with chloroacetyl chloride in the presence of triethyl amine. Finally, one pot intramolecular cyclization of 25 and cleavage was done with NaOMe/ MeOH at room temperature. According to the thin layer chromatography analy-... 

Collect the precipitate on a glass funnel and thoroughly wash with diethyl ether several times to remove unreacted DCC, DMAP, and 4-fluoro-3-nitro benzoic acid. 

Benzoic Acid, 3-nitro-Benzoic Acid, 4-nitro-... 

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