77989-16-3Relevant academic research and scientific papers
The Acid and/or Thermal Mediated Ring Contraction of 4H-1,2,6-Thiadiazines to Afford 1,2,5-Thiadiazoles
Kalogirou, Andreas S.,Kourtellaris, Andreas,Koutentis, Panayiotis A.
supporting information, p. 4056 - 4059 (2016/08/30)
A near-quantitative acid and/or thermal mediated ring contraction of 3′,5′-diarylspiro(benzo[d][1,3]dioxole-2,4′-[1,2,6]thiadiazines) affords 3-aryl-4-(2-arylbenzo[d][1,3]dioxol-2-yl)-1,2,5-thiadiazoles. The reaction scope was studied providing 11 examples of this ring contraction. A double Wagner-Meerwein reaction mechanism is proposed.
Reactions of tetrasulfur tetranitride antimony pentachloride complex (S4N4 SbCl5) with primary β-enaminones and β-enamino esters: Synthesis of 4-substituted 3-aroyl-and 3-ethoxycarbonyl-1,2,5-thiadiazoles
Bae, Su-Hak,Kim, Kyongtae,Park, Young Ja
, p. 159 - 172 (2007/10/03)
The reaction of tetrasulfur tetranitride antimony pentachloride complex (S4N4·SbCl5) with 3-amino-3-alkyl-1-aryl-2-propenones and 3-amino-1,3- diaryl-2-propenones in toluene at 100°C produced 4-substitued 3-aroyl-1,2,5- th
Reactions of 5-substituted 3-alkyl- and 3-aryl-isoxazoles with tetrasulfur tetranitride antimony pentachloride complex (S4N4·SbCl5): Complete regioselective formation of 4-substituted 3-acyl- and 3-aroyl-1,2,5-thiadiazoles and their mechanism of formation
Kim, Kil-Joong,Kim, Kyongtae
, p. 2175 - 2180 (2007/10/03)
The reactions of 3-alkyl- 5a-f, 3-aryl- 5g-m, 3-acylamido- 5n,p, 3-benzamido- 5o and 3-arylamino- 5q -5-alkyl- and -5-aryl-isoxazoles with tetrasulfur tetranitride antimony pentachloride complex (S4N4·SbCl5) in toluene at 90°C to reflux temperature give 3-acyl- 6a-c, e, n-q and 3-aroyl-4-substituted-1,2,5-thiadiazoles 6d, f-m in 13 to 61% yields as single isomers. The same reactions of 3,4-dimethyl- 5s, 5v, 4-ethyl-3-methyl-5t -5-alkyl- and/or 5-aryl-isoxazoles under the same conditions give 3-(1-acetyl-1-chloroethyl)- 8a, 3-(1-benzoyl-1-chloropropyl)- 8b, 3-(1-benzoyl-1-chloroethyl)- 8d, or 3-(1-benzoyl-1-chloroethyl)-4-methyl-1,2,5-thiadiazoles 8c, which are a new type of 1,2,5-thiadiazole derivatives. In addition the reactions with 5-aryl-4-bromoisoxazoles (5,w,y,z) having an electron-donating substituent such as methyl, 4-methyl-phenyl, and 4-methoxyphenyl groups at C3 under the same conditions afford 3-aroyl-4-substituted-1,2,5-thiadiazoles 6d, 6j and 6k, whereas the starting isoxazoles are recovered from the reactions with 5-aryl-4-bromoisoxazoles 5x,z′ having a phenyl or a 4-chlorophenyl group at C3. A plausible mechanism is proposed for the formation of the products.
Reaction of trithiazyl trichloride with active methylene compounds
Duan, Xiao-Guang,Duan, Xiao-Lan,Rees, Charles W.
, p. 2831 - 2836 (2007/10/03)
Activated allylic compounds react with trithiazyl trichloride, (NSCl)3, to give 1,2,5-thiadiazoles 1 and isothiazoles 2. An allylic 2-substituent normally prevents formation of an aromatic 1,2,5-thiadiazole, and isothiazole formation becomes the major pathway. Simple allylic compounds are not very reactive towards (NSCl)3 but a terminal electron withdrawing group (CO2Et) enhances the reactivity. With unsymmetrical allylic compounds, isothiazole formation is regiospecific placing the more electron withdrawing group adjacent to the ring sulfur. 1,3-Diketones give 3-acyl-1,2,5-thiadiazoles; unsymmetrical 1,3-diketones give these thiadiazoles regiospecifically, explicable by cyclisation of an intermediate onto the more reactive carbonyl group. 1,4-Diketones give 3,4-diacyl-1,2,5-thiadiazoles; thus 1,2-dibenzoyl-ethane,-echene and -ethyne all give 3,4-dibenzoylthiadiazole (40-44%). Many of these trithiazyl trichloride reactions provide attractive one-step routes to 1,2,5-thiadiazoles and isothiazoles.
Sulfur Nitride in Organic Chemistry. 9. The Reaction of Tetrasulfur Tetranitride with Benzyl Ketones. Preparation of 3,4-Disubstituted-1,2,5-thiadiazoles
Mataka, Shuntaro,Hosoki, Akira,Takahashi, Kazufumi,Tashiro, Masashi
, p. 1681 - 1685 (2007/10/02)
The reaction of tetrasulfur tetranitride (1) with various aryl and benzyl ketones (2a-o), oxindole (11), benzyl α-pyridyl ketone (12) and α-phenacylpyridine (13) afforded the corresponding 1,2,5-thiadiazoles (3a-n, 11 and 14).The scope and limitations of the above reaction were investigated and the evidences suggesting the radical anion mechanism are presented.
