Category: 31166-29-7

Bunnett, J. F.; Bachman, D. M.; Snipper, L. P.; Maloney, J. H. published the artcile< Chlorination of 2-thiophenecarboxylic acid>, COA of Formula: C5H2Cl2O2S, the main research area is .

2-Thiophenecarboxylic acid (I) 3 g. (0.023 mole), NaOCl 0.042 mole, and excess NaOH in 400 cc. total volume were treated at pH 11.0 and 48° with 25 cc. 6 N HCl for 6 min. The temperature rose to 53°, the pH dropped to 1.3, and a white precipitate formed. After addition of 5 cc. 6 N HCl and 107 g. NaCl, the mixture was cooled and filtered to give 1.75 g. (46%) 5-chloro-2-thiophenecarboxylic acid (II), m. 134-7°, and, after recrystallization and sublimation, m. 149-50°, did not depress the m. p. of II prepared by KMnO4 oxidation of 5-chloro-2-acetylthiophene. Similarly 1.9 g. I (0.015 mole) and 0.037 mole NaOCl gave 0.4 g. (14%) 4,5-dichloro-2-thiophenecarboxylic acid, m. 194-4.5° (from H2O) (cf. m.p. 196-7° of Steinkopf and Kohler in C.A. 32, 3391.1). Oily by-products from several runs were combined to give a considerable fraction of 2,5-dichlorothiophene (III), b. 160-5°, nD16 1.5624; 3,4-dinitro derivative m. 85-5.5°. The by-product oil from a mixture of I and 3 moles NaOCl was a mixture of chlorinated thiophenes, with III the principal constituent.

Journal of the American Chemical Society published new progress about Chlorination. 31166-29-7 belongs to class chlorides-buliding-blocks, and the molecular formula is C5H2Cl2O2S, COA of Formula: C5H2Cl2O2S.

Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics

Steinkopf, Wilhelm; Kohler, Werner published the artcile< Thiophene series. XXXVIII. Chlorine derivatives of thiophene and the limited usefulness of mixed melting points with the isomeric thiophene derivatives>, Application In Synthesis of 31166-29-7, the main research area is .

The fraction of 2-chlorothiophene (I) b. 130-6° yields a chloromercuri derivative (II), m. 223-4°; distillation with 10% HCl gives 86% of pure I, b. 127-8.3° (corrected), m. -70° to -69°, nD19 1.55058. II and I in KI give 67% of 5-chloro-2-iodothiophene, b14 95-6°, m. -25° to -24° (corrected). Refluxing I with yellow HgO in AcOH for 4 h. gives the 3,4,5-tri(acetoxymercuri) complex, transformed by NaCl into the corresponding Cl derivative and this in turn by I in KI into 80% of 2-chloro-3,4,5-triiodothiophene m. 126°; this also results by the action of I upon I in the presence of Hg(OAc)2. I and Br give 80-5% of the 3,4,5-tri-Br derivative, m. 91°. With ClSO3H at -10°, 8 g. I yields 2.4 g. of the 5-sulfonyl chloride, m. 28°. I is separated from III by means of the II derivative, since III does not react with HgCl2. 2,5-Dichlorothiophene (III), b. 161-2°, m. -43.4° (corrected), nD19 1.56077, is purified through the 3,4-bis(chloromercuri) derivative (IV), m. 314-15° (prepared with HgO in AcOH, followed by NaCl). IV and I-KI give the 3,4-di-I derivative (V), m. 83°, and, as an Et2O-insoluble fraction, 2,5,2′,5′-tetrachloro-3,3′-diiodo-4,4′-mercurydithienyl, m. 238°. III and Br give 80% of the 3,4-di-Br derivative, m. 65°. I and AcCl in petr. ether with AlCl3 give 16% of 2,5-dichloro-3-acetothienone, m. 39°. VI, transformed into the Grignard reagent with EtMgBr and reacted with CO2, gives a very small yield of 2,5-dichlorothiophene-3,4-dicarboxylic acid, sublimes about 200°; melting with m-C6H4(OH)2 and ZnCl2 gives a strong green fluorescence. The trichlorothiophene fraction, b. 203-7°, with HgO in AcOH, yields 80% of 2,3,5,2′,3′,5′ -hexachloro-4,4′-mercurydithienyl (VII), m. 242-3°, which has a pale violet color in UV light. VII and HgCl2 in Me2CO yield 89% of 2,3,5-trichloro-4-chloromercurithiophene, m. 211-12°; heating with HCl gives 77% of 2,3,5-trichlorothiophene (VIII), b. 207.7-9.2° (corrected), m. -3.5°, nD19.3 1.58515. The 4-bromomercuric derivative of VIII m. 207° (quant. yield from VII) and has a pale blue-violet color in UV light. VIII gives 90% of the 4-Br derivative, m. 50.5-1.5°, and a quant. yield of the 4-I derivative, m. 51°; both are soluble in 33% oleum with a deep bluish green color. Crude VIII and AcCl with AlCl3 in petr. ether yield 6.5% of 2,3,5 trichloro-4-acetothiophene, m. 80°. VIII and HNO3 in concentrated H2SO4 give the 4-NO2 derivative, m. 70°. Chlorination of 2,5-dibromo-3-iodo-4-thiophenic acid in AcOH yields 2,3,5-trichloro-4-thiophenic acid, m. 176-7°. The 4-sulfonyl chloride of VIII m. 57-8°. The action of EtMgBr upon tetrachlorothiophene gives 2,3,4-trichlorothiophene (IX), b. 209.2-10.2° (corrected), m. -0.5°, nD19.1 1.58588, purified through the 5-chloromercuri derivative (X), m. 211° (18% yield). With HgO in AcOH IX yields 50-5% 2,3,4,2′,3′,4′-hexachloro-5-mercurydithienyl, m. 242-3°, color in UV light bright violet; this also results from X and NaI in Me2CO; with HgBr2 there results a nearly quant. yield of the 5-bromomercuri derivative of IX, m. 207°. X, I and KI give a quant. yield of the 5-I derivative of IX, m. 50-1°, easily colored red by light; the 5-Br derivative, m. 50.5°, results from X and Br-H2O-KBr or from IX and Br2. IX and AcCl with AlCl3 give 59% of 2,3,4-trichloro-5-acetothienone, m. 80°, shows a bright yellow color in UV light. The 5-NO2 derivative of IX, pale yellow, m. 70°. The 5-sulfonyl chloride m. 55-6° (59% yield). 2,3-Dibromo-5-thiophenic acid and Cl2 in AcOH give 2,3-dichloro-5-thiophenic acid, m. 196-7°, sublimes at 120°; boiling with Hg(OAc)2 in AcOH for 3 h. gives 2,3-dichloro-4,5-bis(acetoxymercuri)thiophene (XI), which, transformed into the chloromercuri derivative (XIA), and distilled with HCl, gives 2,3-dichlorothiophene (XII), b. 173-4°, m. -26.2° (corrected), nD21 1.56650; 5-chloromercuri derivative, m. 269-70°; 5-I derivative, m. 27°; 5-Br derivative (XIII), b. 212-14°, m. 6°. 2,3-Dichloro-5-acetothienone, m. 68° (47% yield). XIII and HgO in AcOH, refluxed 5 h., the product treated with NaCl and then with NaI, give 2,3,2′,3′-tetrachloro-5,5′-dibromo-4,4′-mercurydithienyl, m. 238-9°. XII and HNO3 in Ac2O give 37% of the 5-NO2 derivative, pale yellow, m. 55-6°. The 5-sulfonyl chloride (XIV), pale yellow, m. 55-6° (81%). XI or XIA with KI-I gives the 4,5-di-I derivative of XII, m. 72°; XII and Br2 gives 88% of the 4,5-di-Br derivative, m. 67.5°. Heating XIV with a slight excess of 15% NaOH and reduction of the filtrate with 2.5% Na-Hg give 8.4% of 3-chlorothiophene (XV), b. 136-7° (corrected), m. -62°, nD22 1.55322; 2-chloromercuri derivative, m. 137-8°; 2,5-bis(chloromercuri) derivative, decomposes 275°. 3,3′-Dichloro-2,2′-mercurydithienyl, m. 174-5°. XII and EtMgBr, followed by CO2, give 2.8% of 3-chloro-2-thiophenic acid, m. 175-6°. Heating XV with Hg(OAc)2 in AcOH for a short time, then gradually adding I, gives 85% of 3-chloro-2,4,5-triiodothiophene, m. 121°; 2,4,5-triBr derivative, m. 91° (90% yield). The mother liquor from the preparation of XV appears to contain 4-chlorothiophene-2-sulfonic acid, for with PCl5 there results 10% of 2,4-dichlorothiophene, b. 174-5°, m. -34°, nD21.7 1.56866; 3,5-di-Br derivative, m. 72° (85%). Treating 2,5-thioxene with Cl in CCl4 and the residual oil reacted with Br2 give 60% of 3,4 – dichloro – 2,5 – bis(dibromomethyl)thiophene (XVI), m. 112°; in boiling CCl4 Cl2 gives the bis(dichloromethyl) analog, m. 80°. XVI and CaCO3 in H2O, heated 8 h., give 95% of 3,4-dichlorothiophene-2,5-dialdehyde, pale yellow, m. 194°; alk. H2O2 gives a small amount of 3,4-dichlorothiophene-2-aldehyde, with 0.5 mol. H2O, m. 72°, the principal product being the 2,5-dicarboxylic acid (XVII), m. 314-15° (decomposition). XVII, transformed into the 2,5-bis(acetoxymercuri) and then into the chloromercuri derivative and distilled with dilute HCl, yields 65% of 3,4-dichlorothiophene, b. 184.5-5.5°, m. 1°, nD19.6 1.58206; 2 -chloromercuri derivative, m. 206-7°; 2,5-bis(chloromercuri) derivative, m. 347-9°; 2,5-di-I derivative, m. 106°; 2,5-di-Br derivative, m. 75°. AcCl gives 88% of 3,4-dichloro-2-acetothienone, m. 56°. 3,4-Dichloro-2,5-bis(dibromomethyl)thiophene and Na2CO3 give a poor yield of 3,4-dichloro-2-hydroxymethylthiophene-5-carboxylic acid, m. 220-1°. 2,4,5-Tribromo-3-thiotolene and Cl2 in CCl4 give 3,4-dichloro-2,5-bis(dichloromethyl)thiophene, which yields with EtOH-KOH 2,4,5-trichloro-3-thiotolene, b23 115-16°, m. -18° (corrected), nD21.5 1.56617. 2,4,5-Triiodo-3-thiotolene and Cl2 in CHCl3 (with cooling), followed by EtOH-KOH, give 3-methyl-2,2,3,4,4,5,5-heptachlorotetrahydrothiophene, m. 217-18.5°. Exhaustive chlorination of thiophene or 2-thiophenic acid in AcOH gives 2,3,3,4,5(or 2,2,3,4,5)pentachloro-2,3-dihydrothiophene, b13 122-6°. 2,5-Thioxene and Br2 in CS2 give 85% of 3,4-dibromo-2,5-bis(dibromomethyl)thiophene, m. 132°; Cl2 gives a quant. yield of the dichloromethyl analog, m. 103°; CaCO3 in H2O gives 3,4-dibromothiophene-2,5-dialdehyde, pale yellow, m. 227°; aqueous KMnO4 gives 45% of the 2,5-dicarboxylic acid, m. 317-18°; long treatment with Cl2 in AcOH gives 49% of the acid. 2,3-Dibromo-5-thiophenic acid gives with Hg(OAc)2 in AcOH, followed by formation of the chloromercuri salt and distillation with dilute HCl, 2,3-dibromothiophene, b. 218.6-19.6°, m. -17.5°, nD22.8 1.63039. 2-Thiotolene and Br2-H2O give the tetra-Br derivative, m. 115-17°. The mixed m. ps. of isomeric thiophene derivatives are discussed and illustrated by several examples, showing that this method cannot be used to distinguish the higher halogenated derivatives Certain thiophene and selenophene derivatives have approx. the same m. ps. and mixed m. ps. The possibility of using luminescent anal. for distinguishing between these derivatives is also discussed.

Justus Liebigs Annalen der Chemie published new progress about Melting point. 31166-29-7 belongs to class chlorides-buliding-blocks, and the molecular formula is C5H2Cl2O2S, Application In Synthesis of 31166-29-7.

Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics

Profit, E.; Solf, G. published the artcile< Chlorothiophenes>, COA of Formula: C5H2Cl2O2S, the main research area is .

The four isomeric dichlorothiophenes, 2,3- (I), 2,4- (II), 3,4- (III), and 2,5-dichlorothiophenes (IV), were examined relative to their reactivities in the Friedel-Crafts reaction. With β-chloropropionyl chloride (V), the resp. isomeric chloro ketone was synthesized in high yield. They showed local anesthetic activity about 5 times as strong as cocaine and about one half as strong as Falicain. The preparation of the four isomeric dichlorothiophenecarboxaldehydes in good yields was described. The chem. characteristics of 2,3-dichloro-5-acetylthiophene (VI) were studied. Some of the reactions of 2,3,5-trichlorothiophene (VII) were also studied. 2,3-Dichloro-4,5-thiophenedicarbox-aldehyde (0.5 g.) in 30 ml. 50% alc. refluxed 5 min. with 0.3 g. N2H4·H2O gave 0.3 g. 2,3-dichlorothieno[4,5-d]pyridazine, m. 194-5°. I (7.7 g.) and 8.1 g. V in 150 ml. CS2 treated under stirring and cooling with 7 g. AlCl3, then stirred 2 hrs. at room temperature, and decomposed gave 11.6 g. β-chloroethyl 2,3-dichloro-5-thienyl ketone (VIII), m. 67-8°. The following IX and their thiosemicarbazones or hydrazones were similarly obtained (R, % yield, m.p., derivative, and m.p. of derivative given): Me, 96, 66°, thiosemicarbazone, 217-18°; Et, 86, 56-7°, thiosemicarbazone, 184-6°; Pr, 78, 32-3°, thiosemicarbazone, 161°; Ph, 68, 62-3°, p-nitrophenylhydrazone, 201-3°; PhCH2, 93, 93°, p-nitrophenylhydrazone, 235-7°. VIII (1.2 g.) in 3.5 ml. alc. refluxed 10 hrs. gave 0.7 g. β-ethoxyethyl 2,3-dichloro-5-thienyl ketone, m. 17.5°. VIII (1.2 g.) in 3 ml. AcOH heated several minutes with 0.65 g. KOAc gave 1.3 g. β-acetoxyethyl 2,3-dichloro-5-thienyl ketone, m. 55-6°. VIII (1.2 g.) kept several days with 10 ml. C5H5N gave 1.1 g. IX (R = β-pyridiniumethyl chloride), m. 184-5° (decomposition). VIII (1.2 g.) in 10 ml. MeOH refluxed a short time with 0.6 g. KOAc, cooled, 0.7 g. α-naphthylamine in 10 ml. alc. added, and the mixture kept a short time gave 0.9 g. IX [R = β-(α-naphthylamino)ethyl] (X), m. 83-4°. IX.HCl (R = R1CH2CH2) (XI) were obtained by the following procedures: (A) As in the preparation of X the reaction mixture was poured into dilute HCl, unreacted ketone removed with Et2O, the aqueous solution made alk., extracted with Et2O, and the dried ethereal solution treated with dry HCl. (B) VI (3.9 g.), 0.025 mol. secondary amine-HCl, and 1 g. paraformaldehyde in 20 ml. alc. containing 2 drops concentrated HCl was refluxed 12 hrs. The following XI were thus obtained (R1, % yield, and m.p. given): Me2N, 60, 201-2°; Et2N, 74, 124-6°; piperidino, 77, 196-7°; 4-methylpiperidino, 59, 189-90°; 4-ethylpiperidino, 93, 197-8°; 4-propylpiperidino, 63, 199°; morpholino, 94, 208-10°. VIII (1.2 g.) in 10 ml. alc. refluxed with 0.35 g. KCN in 3 ml. H2O gave 1 g. IX (R = CH2CH2CN) (XII), m. 124-5° (cyclohexane). XII (1 g.) in 20 ml. concentrated HCl refluxed 4 hrs. gave IX (R = CH2CH2CO2H) (XIII), m. 120-1°. VIII (1.2 g.) in 3 ml. alc. refluxed with 0.7 g. NH2OH.HCl and 0.85 g. KOH in 5 cc. H2O gave 1.1 g. N,N-bis[β-(2,g-dichloro-5thenoyl)ethyl]hydroxylamine, m. 159-60°. 2,3-Dichloro-5chloroacetylthiophene (XIV), m. 61-2°, was prepared in 84% yield. XIV (1.15 g.) in 15 ml. C5H5N kept 1 day gave quant. IX (R = pyridiniummethyl chloride). XIV (2.3 g.) in 15 ml. alc. treated under cooling with 1.7 g. ammonium dithiocarbamate in alc. and kept 4 days at room temperature gave 2.3 g. 2-mercapto-4-(2,3-dichlorothien-5-yl)thiazole,m. 181-2°. I (0.05 mole) and 0.05 mole dicarboxylic monoester monochloride in 80 ml. CS2 treated under ice-cooling with 7.2 g. AlCl3, then stirred 3 hrs. at room temperature, and poured over ice gave the following XV (R, n, % yield, and m.p. given): Et, 0, 30, 57°; Me, 2, 44, 65-6°; Me, 3, 62, 67-8°; Me, 4, 47, 63-4°. XV refluxed in dilute aqueous KOH gave a nearly quant. yield of the corresponding acid (XVI) (n, % yield, and m.p. given): 0, quant., 126-7°; 2, quant., 120-1°; 3, quant., 113-15°; 4, quant., 93-4°; 5, 14, 86-8°. I (7.7 g.) and 3.9 g. succinoyl chloride in 50 ml. CS2 treated at -12° with 7 g. AlCl3, kept 40 min. at -10°, decomposed with ice, and the solids collected gave 0.6 g. 1,4-bis(2,3-dichloro-5-thienyl)-l,4- butanedione, m. 188-90°. 2,3-Dichloro-5-thenoylpropionic acid was obtained in 23.8% yield from the filtrates upon acidification. Similarly, 7.7 g. I and 4.5 g. glutaryl chloride with AlCl3 gave 4 g. 1,5-bis(2,3-dichloro-5-thienyl)-1,5-pentadione, m. 115°; thiosemicarbazone (21% yield) m. 220-2° (decomposition). 1,6Bis(2,3-dichloro-5-thienyl)-1,6-hexanedione, 82% yield, m. 133°, and 1,7-bis(2,3-dichloro-5-thienyl)heptane-1,7-dione, 42% yield, m. 74-5°, were similarly prepared The latter also afforded 14% 2,3-dichloro-5-thienylcaproic acid from the acidified filtrate. 2,3Dichloro-5-acetylthiophene semicarbazone m. 264-6°. VI (17.7 g.) treated with 10 g. (iso-PrO)3Al in 50 ml. iso-PrOH gave 14.5 g. α-(2,3-dichloro-5-thienyl)ethylcarbinol, b0.2 93-4°. VI (19.5 g.) added at 70° to 43 g. NaOH in 55 ml. H2O into which 32 g. Cl had been previously passed, the mixture stirred, treated with 10 g. NaHSO3, and the product acidified with concentrated HCl gave 16.2 g. 2,3-dichloro-5-thiophenecarboxylic acid (XVII), m. 194-6°. XVII (14 g.), 45 g. quinoline, and 4 g. Cu powder refluxed 2 hrs. under N gave 7.4 g. I, b10 55°,n20D 1.5651. I(5.1g.) in 50 cc. CS2 treated with 4.4 g. AlCl3 under ice-cooling, and the mixture treated in 10 min. with Cl2CHOMe, warmed 5 min. at 50°, and decomposed gave 4.85 g. 2,3-dichloro-5-thiophenecarboxaldehyde (XVIII), m. 56°. XVIII (1.81 g.) in 20 ml. MeOH treated with 2.3 g. dianilinoethane in 40 ml. MeOH gave 1.7 g. 1,3-diphenyl-2- (2,3-dichloro-5-thienyl)tetrahydroimidazole, m. 126-6.5°. VI (9.8 g.) refluxed 4 hrs. with 6 g. SeO2 in dioxane and kept overnight gave 7.9 g. 2,3-dichloro-5-thienylglyoxal (XIX), m. 94 5°; oxime m. 160°; semicarbazone m. 135-7°; thiosemicarbazone m. 191° (decomposition). XIX (0.22 g.) and 0.1 g. o-C6H4(NH2)2 in 5 ml. 50% alc. afforded an almost quant. yield of 2-(2,3-dichloro-5-thienyl)quinoxaline, m. 209-10°. VI (19.5 g.) kept 3 days at room temperature with 40 g. Zn-Hg and 80 ml. 5% HCl and refluxed 1 hr. with 10 ml. concentrated HCl gave 5.5 g. 2-ethyl-4chlorothiophene (XX), b14 67-8°, n20D 1.5399. XX (2 g.) treated in the cold with 4 ml. fuming HNO2 and 4 ml. Ac2O, shaken 2 hrs. at 0°, and distilled gave 1.9 g. 2-nitro-3-chloro-5-ethylthiophene, b14 158-60°. VI (19.5 g.) and 20 ml. 84% N2H4·H2O heated with 80 ml. (CH2OH)2, refluxed, H2O distilled until temperature reached 165°, treated at 90 o with 20 g. KOH, refluxed 1.5 hrs., and fractionated gave 2.4 g. 3-chloro-5-ethylthiophene, b14 67-8°, and 4.2 g. 2,3dichloro-5-ethylthiophene, b13 87-90°, n22D 1.5458. I (115 g.) in 200 ml. C6H6 treated with Na Hg amalgam gave 71 g. unchanged I and 6.3 g. 3-chlorothiophene (XXI), b. 135-7°. XXI (1.18 g.) and 0.9 g. AcCl in 20 ml. CS2 treated in the cold with 1.5 g. AlCl3 gave 1.2 g. 3-chloro-2-acetylthiophene (XXII), b15 117-18°. XXII treated with NaOCl in alk. solution gave 3-chlorothiophene-2-carboxylic acid (XXIIa), m. 183-5°. XXI (2.9 g.) and 3.7 g. HCONMe2 treated with 7.5 g. POCl3 gave 1.3 g. 3-chlorothiophene-2-carboxaldehyde (XXIII), b14 100-1°; semicarbazone m. 214-16°; thiosemicarbazone m. 213-14°. XXIII oxidized with KOH-H2O2 gave XXIIa. I (15.3 g.) and 24 ml. Ac2O treated at -20° with 20 ml. fuming HNO3 and 25 ml. Ac2O gave 11.7 g. 2,3-dichloro-5-nitrothiophene (XXIV), m. 56° XXIV (2 g.) in 10 ml. MeOH kept 1 hr. with 2 g. KOH in 20 ml. MeOH gave 0.7 g. 2-methoxy-3-chloro-5-nitrothiophene, m. 62°. XXIV (1 g.) in 20 ml. alc. left 16 hrs. at room temperature with 0.85 g. piperidine gave 0.8 g. 2-piperidino-3-chloro-5-nitrothiophene, m. 57-8°. Similarly, 1 g. XXIV and 1 g. 4-ethylpiperidine gave an almost quant. yield of 2-(4-ethylpiperidino)-3-chloro-5-nitrothiophene, m. 6970°. XXIV (1 g.) and 0.9 g. morpholine in alc. gave an almost quant. yield of 2-morpholino-3-chloro-5-nitrothiophene, m. 1045°. XXIV (1 g.) in 10 ml. alc. treated 15 min. with 1.1 g. PhSH and 1 g. NEt3 gave 0.9 g. 2-phenylthio-3-chloro-5-nitrothiophene, m. 96-7°. Similarly prepared were 53% 2-(p-tolylthio)-3chloro-5-nitrothiophene, m. 81-2°, and almost quant. 2-(pchlorophenylthio)-3-chloro-5-nitrothiophene, m. 93-4°. XXIV (5 g.) and 20 g. Zn granules stirred 2 hrs. at room temperature with 100 ml. concentrated HCl followed by acetylation gave 2.1 g. 3-chloro-5 acetamidothiophene (XXV), m. 191-2°. XXIV was similarly converted into 3-chloro-5-propionylaminothiophene (XXVI), m. 159°. XXV (1.8 g.) in 20 ml. Ac2O treated under stirring at -20° with 12 ml. fuming HNO3 and 15 ml. Ac2O, stirred 1 hr. at -10°, and stirred until the temperature reached 5° gave 1.3 g. 2,4dinitro-3-chloro-5-acetamidothiophene, m. 239-40°. XXVI similarly gave 92% 2,4-dinitro-3-chloro-5-propionylaminothiophene, m. 164-5°. A mixture of II and III (40 g.) in 1600 ml. alc. kept 4 weeks with 850 ml. cold saturated HgCl2 and 90 ml. 33% NaOAc gave 2,4-dichloro-5-chloromercurithiophene (XXVII), m. 183-5°. Crude XXVII dissolved in 400 ml. 2N HCl and steam distilled gave II, b12 54°, n20D 1.5660. II (1 g.), 0.7 g. ClCH2COCl, and 10 ml. CS2 treated with cooling with 1 g. AlICl3 gave 0.8 g. 2,4-dichloro-5-chloroacetylthiophene, m. 76-7°. The following 2,4-dichloro analogs of IX were similarly prepared (R, % yield, m.p., derivative, and m.p. derivative given): Me, 78, 35°; thiosemicarbazone, 215-16° (decomposition); Et, 87, 53°; thiosemicarbazone 169-70° (decomposition); Ph, 73, 32.5-33°, 2,4-dinitrophenylhydrazone, 225-7° (decomposition); PhCH2, 56, 29-30°, 2,4-dinitrophenylhydrazone, 185-7° (decomposition); CH2CH2Cl, 88, 40.5-1.5°, -, -. II (5.1 g.), 4 g. Cl2CHOMe, 40 ml. CS2, and 4.4 g. AlCl3 gave 5 g. 2,4-dichlorothiophene-5-carboxaldehyde (XXV-III), m. 35-6°; oxime m. 144-6°; semicarbazone m. 244-6°; thiosemicarbazone m. 238-40° (decomposition); p-nitrophenylhydrazone m. 264-6° (decomposition); nitromethylene derivative m. 90-1°. Oxidation of XXVIII with perhydrol in aqueous KOH gave quant. 2,4-dichlorothiophene-5-carboxylic acid, m. 186-7°. Nitration of II with fuming HNO3 in Ac2O at -15° gave 63% 2,4-dichloro-5-nitrothiophene (XXIX), b14 119°. XXIX was further nitrated with fuming HNO3 and H2SO4 to give 70.4% 2,4-dichloro-3,5-di-nitrothiophene, m. 97-8°. III (3 g.) and 2 g. ClCH2COCl in 20 ml. CS2 treated in the cold with 2.8 g. AlCl3 gave 4.2 g. 2-chloro-acetyl-3,4-dichlorothiophene, m. 70-1°. The following 2-acyl-3,4-dichlorothiophenes were obtained (R in 2-COR, % yield, m.p., derivative, and m.p. derivative given): Me, 87, 54°, thio-semicarbazone, 171-2°; Et, 71, 68°, thiosemicarbazone, 156-7°; Pr, 69, 43°, thiosemicarbazone, 114-15°; Ph, 67, 97-7.5°, 2,4-dinitrophenylhydrazone, 202-4° (decomposition); PhCH2, 68, 77-8°, 2,4-dinitrophenylhydrazone, 181-3° (decomposition); ClCH2CH2, 88, 61-2°, -, -. β-Chloroethyl 3,4-dichloro-2-thienyl ketone (1.2 g.) and 0.5 g. KOAc in 10 ml. MeOH refluxed a short time, then 10 min. with 0.5 g. morpholine, and treated with 60 ml. 4N HCl gave 1.5 g. β-morpholinoethyl 3,4-dichloro-2-thienyl ketone-HCl, m. 197-9°. III (5.1 g.) in 20 ml. Ac2O treated at -20° with 5 ml. fuming HNO3 and 10 ml. Ac2O gave 5.5 g. 2-nitro-3,4-dichlorothiophene (XXIXa), m. 72°. XXIXa (0.55 g.) in 10 ml. fuming HNO3 and concentrated H2SO4 gave 0.55 g. 2,5-dinitro-3,4-dichlorothiophene, m. 123-4°. III (5.1 g.), 4 g. Cl2CHOMe, and 4.4 g. AlCl3 in 40 ml. CS2 gave 3.4 g. 3,4-dichlorothiophene-2-carboxaldehyde (XXX), m. 61-2°; oxime m. 1513°; semicarbazone m. 257-8° (decomposition); thiosemicarbazone m. 226-8° (decomposition). Oxidation of XXX with perhydrol-KOH gave an almost quant. yield of 3,4-dichlorothiophene-2-carboxylic acid, m. 187-8°. III (5.1 g.) treated dropwise in 10 min. with 15 ml. 30% oleum, stirred 1 hr. at room temperature, poured on ice, and the crude product treated with PCl5 4 hrs. at 140° gave 6.5 g. 3,4-dichlorothiophene-2,5-bis(sulfonyl chloride) (XXXI), m. 13840°. XXXI (3.5 g.) refluxed 15 min. with 50 ml. concentrated NH4OH gave 1.8 g. 3,4-dichlorothiophene-2,5-disulfonamide, m. 278-80° (decomposition). IV (15.3 g.), 16.2 g. V, and 14 g. AlCl3 in 100 ml. CS2 stirred 5 hrs. gave 15.6 g. β-chloroethyl 2,5-dichloro-3-thienyl ketone (XXXII), m. 33-4°. XXXII (1.2 g.) in 10 ml. alc. heated with 0.3 g. KCN in 3 ml. H2O gave 1.15 g. the β-cyanoethyl analog (XXXIII), m. 67-8°. XXXIII (1.15 g.) in 40 ml. concentrated HCl refluxed 4 hrs. gave 0.2 g. β-(2,5-dichloro-3-thenoyl)propionic acid, m. 116-17°. The following 2,5-dichloro-3-thienyl βaminoethyl ketone-HCl salts were prepared as described above (R of the β-COCH2CH2R group, % yield, and m.p. given): piperidino, 91, 188-9°; 4-methylpiperidino, 71, 184-6°; 4-ethylpiperidino, 70, 183-5°; 4-propylpiperidino, 73, 167-9°; morpholino, 85, 194-6°. IV (15.3 g.), 14 g. AlCl3, and 11.5 g. Cl2CHOMe in 100 ml. CS2 gave 6.3 g. 2,5-dichlorothiophene-3-carboxaldehyde, m. 24-4.5% b15 105-6°; oxime m. 129-31°. VII (62 g.) treated 17 hrs. with 7.8 g. AcCl and 14 g. AlCl3 gave 7.1 g. 2,3,5-trichloro-4-acetylthiophene, m. 79°; thiosemicarbazone m. 230-3° (decomposition). The following compounds were similarly prepared: 47% 2,3,5-trichloro-4-propionylthiophene, m. 55-6° [thiosemicarbazone m. 215-16° (decomposition)]; 6% 2,3,5-trichloro-4 butyrylthiophene, m. 34° [thiosemicarbazone m. 178-9° (decomposition)]; 11% 2,3,5-trichloro-4-phenacylthiophene, m. 119°.

Journal fuer Praktische Chemie (Leipzig) published new progress about Reactivity (chemical). 31166-29-7 belongs to class chlorides-buliding-blocks, and the molecular formula is C5H2Cl2O2S, COA of Formula: C5H2Cl2O2S.

Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics

Belen’kii, L. I.; Gromova, G. P.; Krayushkin, M. M. published the artcile< Protonation and electrophilic trichloromethylation of 2,5- and 2,4-dichlorothiophenes>, Application In Synthesis of 31166-29-7, the main research area is electrophilic trichloromethylation chlorothiophene; protonation chlorothiophene.

Trichloromethylation of 2,5-dichlorothiophene (I) and 2,4-dichlorothiophene (II) with CCl4 and AlCl3 has been studied. The reaction of I was directed to position 3 with formation of 2,5-dichloro-3-(trichloromethyl)thiophene, the process being complicated by the formation of the isomeric 3,5-dichloro-2-(trichloromethyl)thiophene (III), and 4,5-dichloro-2-(trichloromethyl)thiophene, as well as linked products, i.e. a mixture of bis(dichlorothienyl)dichloromethanes. Trichloromethylation of II smoothly leads to III, along with a small amount of bis(3,5-dichloro-2-thienyl)dichloromethane. It was also found that as a result of protonation under the effect of HCland AlCl3, I was converted into II, which, under the reaction conditions exists in the form of σ-complex, i.e. the 2H-3,5-dichlorothiophenium ion, stable at room temperature The mechanism of trichloromethylation of I, including the ipso-attack by the CCl3+ cation and isomerization during protonation, is discussed.

Gazzetta Chimica Italiana published new progress about 31166-29-7. 31166-29-7 belongs to class chlorides-buliding-blocks, and the molecular formula is C5H2Cl2O2S, Application In Synthesis of 31166-29-7.

Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics