Preparation of 5-nitroisothiazolone and derivatives was written by Ponci, R.;Baruffini, A.;Croci, M.;Gialdi, F.. And the article was included in Farmaco, Edizione Scientifica in 1963.Safety of N-Benzyl-2-chloro-5-nitrobenzamide The following contents are mentioned in the article:
Adding a solution of KOH in EtOH with stirring to 80 g. 2,5-Cl(O2N)C6H3CO2H (I) in 300 cc. EtOH and concentrating to dryness at 40° gave I K salt. Powd. and dried I K salt (24 g.) was suspended in 220 cc. absolute EtOH, the mixture heated to boiling, 0.05 mole freshly prepared Na2S2 in 96% EtOH added with stirring in 90 min., and the mixture heated 1 hr. to give 65-70% yellow [2,4-HO2C(O2N)C6H3]2S (II), m. 280° (decomposition) (AcOH). A suspension of 6 g. II in anhydrous PhMe and 7 g. PCl5 was refluxed 2.5 hrs. to give 6.5 g. yellow [2,4-ClOC(O2N)C6H3]2S (III), m. 229-30° (dioxane). III was converted with refluxing absolute EtOH to [2,4-EtO2C(O2N)C6H3]2S, m. 169° (benzene-petr. ether). Powd. 2,5-Cl(O2N)C6H3CO2H was covered with SOCl2 and the mixture refluxed 1.5 hrs. to give 90% 2,5-Cl(O2N)C6H3COCl (IV), m 60-1° (ligroine). IV was converted to the following 2,5-Cl(O2N)C6H3CONHR (V) with a dioxane solution of the appropriate amine (or by bubbling in NH3) (R and m.p. given): H, 178°; Ph, 158°; Bu, 136°; PhCH2, 195°; 3-pyridylmethyl, 201°. III and a dioxane solution of the appropriate amine (method A) or 0.02 mole V and 0.01 mole freshly prepared Na2S2 in EtOH refluxed 90 min. (method B) gave the following: [2,4-ROC(O2N)C6H3]2S (VI) (method, R, and m.p. given): A, NH2, 250° (decomposition); A, MeNH, 255° (decomposition); A or B, BuNH, 215-18°; B, PhCH2NH, 243-5°; A, piperidino, 183°; A or B, PhNH, 241-3°; A, p-ClC6H4NH, >230° (decomposition); A or B, 3-pyridylmethylamino, 194-5°. Treating V (R = PhCH2NH) (VII) with an equivalent amount of Na2S2.9H2O gave 2,5-EtO(O2N)C6H3CONHCH2Ph (VIII), m. 151° (EtOH), which was also obtained directly from VII and alc. NaOH. VII and methanolic NaOH gave 2,5-MeO(O2N)C6H3CONHCH2Ph, m. 108° (benzene-petr. ether). Heating 1 mole 2,5-EtO(O2N)C6H3COCl, m. 80° (prepared from the corresponding acid, m. 161-3°, and SOCl2) with 2 moles PhCH2NH2 in 10% dioxane 20 min. at 50° gave VIII. III (5 g.) in 150 cc. anhydrous (CHCl2)2 was treated with 4 cc. Br, the mixture refluxed 90 min., excess Br removed in vacuo, the solution concentrated to half volume, anhydrous CCl4 added in 2 80-cc. portions, and the solution concentrated to 70 cc., and filtered. Then, 12 cc. 20% aqueous NH3 was introduced slowly with vigorous stirring at <20°, and the mixture kept 2 hrs. at ambient temperatures to give about 3 g. yellow IX (R = H), m. >280° (AcOH) (method C). Refluxing 1 g. VI(R = NH2) in 50 cc.(CHCl2)2 with 1.5 cc. Br 6 hrs. gave 0.4 g. IX (R = H) (method D). The following IX were thus prepared (method, R, and m.p. given): C or D, Me, 229-30°; C or D, PhCH2, 142°; C or D, Ph, 228°; C, p-C6H4Cl, 215-17°; C, Bu, 79°. The last compound was also prepared by suspending 2.17 g. III in 40 cc. anhydrous (CHCl2)2, adding 6 drops of 20% oleum, and heating at 50-60° while introducing a fast stream of Cl. The excess Cl was removed in a stream of dry N and the filtered solution dropped into 20 cc. anhydrous CCl4 containing 4.4 g. BuNH2. After standing 1 hr. at ambient temperatures, the mixture was extracted with very cold dilute HCl and then washed with H2O. The identity of IX was confirmed by conversion to the corresponding 5-nitrosaccharins (X). To a suspension of 3 g. IX (R = H) in 30 cc. AcOH was added 10 cc. 30% H2O2 and the mixture heated 60 min. at 100° to give X (R = H), m. 213-16° (method E). An ethereal solution of 2 g. 2,4-Cl(O2N)C6H3SO2Cl was dropped with stirring into 5 cc. 20% NH3 with cooling. The mixture was kept 2 hrs. at ambient temperatures, concentrated, and dried in vacuo at low temperature A 1-g. portion of the residue was dissolved in 100 cc. H2O, passed through a 2-cm. diameter column containing 40 g. Amberlite C.G. 120 activity, and eluted with 150 cc. H2O to give X (R = H) (method F). X (R = Na) (1 g.) in 5 cc. HCONMe2 was heated slowly to reflux with 2 equivalents MeI and the mixture refluxed 15 min. to give 70% X (R = Me) (method G). The following X were also prepared (method, R, and m.p. given): E, Me, 170°; E or G, Bu, 74°; E or G, PhCH2, 139°; E or F, Ph, 203°; E, p-C6H4Cl, 181°. Dried and powd. 7 g. II was added in small portions with stirring to 50 cc. HNO3 (d. 1.52) kept at 0°, the mixture kept 30 min. with stirring at ambient temperatures, and 100 cc. 10% K2CO3 added dropwise with external cooling to give 8.5 g. 2,4-HO2C(O2N)C6H3SO3K (XI). A suspension of 6.1 g. 2,5-H2N(O2N)C6H3Me in 20 cc. concentrated HCl was cooled to -5° and diazotized with 2.8 g. NaNO2 in 10 cc. H2O. The mixture was poured slowly with stirring into AcOH saturated with SO2, and 2 g. CuCl2.2H2O dissolved in a min. amount of H2O was added. The mixture was allowed to warm to 20°, stirred until gas evolution had ceased, and diluted with 240 cc. H2O to precipitate 2,4-Me(O2N)C6H3SO2Cl (XII). XII was suspended in 60 cc. 5% KOH, heated to solution, treated with 120 cc. 10% KMnO4, and heated until the color of KMnO4 disappeared to give 3 g. XI. XI was converted to the acid chloride with PCl5 in the usual manner. Dissolving X (R = H) in 100 cc. EtOH, adding a stoichiometric amount of EtONa in EtOH, and allowing the mixture to stand in ice several hrs. gave X (R = Na). This study involved multiple reactions and reactants, such as N-Benzyl-2-chloro-5-nitrobenzamide (cas: 83909-69-7Safety of N-Benzyl-2-chloro-5-nitrobenzamide).
N-Benzyl-2-chloro-5-nitrobenzamide (cas: 83909-69-7) belongs to amides. Amides are pervasive in nature and technology. Proteins and important plastics like Nylons, Aramid, Twaron, and Kevlar are polymers whose units are connected by amide groups (polyamides); these linkages are easily formed, confer structural rigidity, and resist hydrolysis. Amides can be recrystallised from large quantities of water, ethanol, ethanol/ether, aqueous ethanol, chloroform/toluene, chloroform or acetic acid. The likely impurities are the parent acids or the alkyl esters from which they have been made. The former can be removed by thorough washing with aqueous ammonia followed by recrystallisation, whereas elimination of the latter is by trituration or recrystallisation from an organic solvent.Safety of N-Benzyl-2-chloro-5-nitrobenzamide
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics