24622-33-1

Upstream product

• 13140-47-1 N-n-propyl-N'-phenylthiourea 
• 107-10-8 propylamine 
• 103-72-0 phenyl isothiocyanate 
• 75-15-0 carbon disulfide 
• 615-43-0 2-iodophenylamine 
• 95-16-9 1,3-Benzothiazole 
• 2516-40-7 2-bromo-1,3-benzothiazole 
• 615-20-3 2-chlorobenzo[d][1,3]thiazole 

Downstream Products

• 108656-83-3 C₁₁H₁₄N₂S 

Relevant academic research and scientific papers

Method for synthesizing benzothiazole by microwave radiation of benzothioamide compound in aqueous phase

The invention discloses a method for synthesizing benzothiazole by microwave radiation of a benzothioamide compound in an aqueous phase. The method includes the steps: adding the benzothioamide compound into the aqueous phase under microwave conditions; performing cyclization under alkaline conditions to generate the benzothiazole. The method for preparing the benzothiazole is environmentally friendly, simple and convenient in operation, safe, cheap and efficient. Compared with the prior art, the method is applicable to a lot of functional groups, high in yield, few in by-products, simple in operation, safe, low in cost and environmentally friendly.

Metal-Free Synthesis of 2-Aminobenzothiazoles via Iodine-Catalyzed and Oxygen-Promoted Cascade Reactions of Isothiocyanatobenzenes with Amines

In this paper, a highly efficient and sustainable synthesis of 2-aminobenzothiazoles through the cascade reactions of isothiocyanatobenzenes with primary or secondary amines by using iodine as a catalyst and oxygen as an oxidant is presented. Mechanistically, the formation of the title compounds involves the in situ formation of the required benzothiourea intermediate followed by its intramolecular cross dehydrogenative coupling of a C(sp2)-H bond and a S-H bond. To our knowledge, this should be the first example in which 2-aminobenzothiazoles are efficiently prepared from simple and cheap isothiocyanates and amines under metal-free conditions by using iodine as a catalyst and molecular oxygen as an oxidant with water as the byproduct. Compared with literature protocols, this method eliminates the use of ortho-halo-substituted precursors, expensive transition-metal catalysts, and hazardous oxidants.

Synthesis method of 2-aminobenzothiazole compounds

The invention discloses a preparation method of 2-aminobenzothiazole compounds. The 2-aminobenzothiazole compounds is prepared from the following steps of dissolving phenyl/naphthalene isothiocyanateand primary amine into a solvent, adding a catalyst iodine and an oxidant, carrying out one-pot multi-step tandem reaction to prepare the 2-aminobenzothiazole compounds under the temperature of 80 to 150 DEG C. The synthesis method has the advantages that raw materials are cheap and easily available, the reaction condition is mild, the substrate application range is broad, atom economy is high, requirements of green chemical are met, and a novel method which is economical and practical and green and environmentally friendly is provided for synthesis of the 2-aminobenzothiazole compounds.

Structure-activity relationship of dihydroimidazo-, dihydropyrimido, tetrahydrodiazepino-[2,1-b]-thiazoles, and -benzothiazoles as an acylation catalyst

Cyclic isothioureas 1, 2, 3, and 4 were synthesized through a four-step procedure from the corresponding ortho-bromoanilines 10 via Pd- or Cu-catalyzed cyclization-benzothiazole formation. Nonbenzo analogues 7, 8, and 9 were synthesized by a condensation reaction of cyclic thioureas 15 and α-bromoacetophenones 14. Investigations of the acylation reactions of 1-phenylethanol with acid anhydrides in the presence of these cyclic isothiourea catalysts revealed their structure-activity relationships. Remarkable electronic effects resulting from substituent(s) on a benzo or phenyl moiety and the influence of the size of the annulating ring were observed. Introduction of an electron-donating substituent(s) enhanced the reaction rate. A few substitution effects on chiral catalysts of type 3 and 7 were also studied.

Direct amination of azoles using CuCl2 complexes of amines under mild conditions

The efficient direct amination of azoles, including benzoxazole, benzothiazole and 1-methylbenzimidazole, was accomplished in moderate to good yields using CuCl2 complexes of amines as a readily available and effective nitrogen source. The coupling reactions were performed under mild conditions: at 30-50°C within 3-6 h, in air without oxidant, additive, ligand and anhydrous conditions.

Convenient and reliable routes towards 2-aminothiazoles: Palladium-catalyzed versus copper-catalyzed aminations of halothiazoles

Two efficient methods for the amination of 2-halothiazoles are presented here. A first protocol requires a Pd/L system. Several 2-aminothiazoles were synthesized under optimized conditions and isolated in good yields. The first palladium-catalyzed C-N coupling reactions between 2-halothiazoles and primary alkylamines are presented. In a second part, ligand-free copper-catalyzed aminations of 2-halothiazoles by alkylamines and aniline in a green solvent have been developed. The protocol is very effective for primary and secondary amines and perfectly tolerates the presence of another halide moiety on the 2-halothiazole. The reaction occurs under the assistance of microwave irradiation, which drastically decreases the reaction time. The reaction leads to the formation of 2-aminothiazoles, key molecules in pharmaceutical research. Copyright

Laccase-catalysed homocoupling of primary aromatic amines towards the biosynthesis of dyes

Coloured disubstituted benzoquinonimine trimeric structures are obtained as main reaction products of the oxidation of p-electron donor pri-mary aromatic amines using two different laccases, CotA-laccase from Baccilus subtilus and TvL from Trametes versicolor. These orange-red to purple products, presenting high molar extinction coeffi-cients, presumably result from oxidative homocou-pling reactions, through the formation of N-C bonds at positions 2 and 5, of the laccase oxidised inter-mediate as showed in the proposed oxidative path-way. The product of 1,4-phenylenediamine is shown to be the trimer known as Bandrowski's base which has an established role in hair and fur dyeing. Our results also show that the occurrence and/or rates of oxidation of aromatic amines are strongly dependent on the presence of p-electron releasing substituents in the aromatic ring and are independent on the properties of the enzyme used. Overall our data con-tribute for (i) understanding key features of laccase reactivity with p-substituted aromatic amines and (ii) establishing enzymatic processes that lead to the syn-thesis of coloured bio-products under mild condi-tions with potential impact in the cosmetic and dye industries.

Synthesis of 2-N-substituted benzothiazoles via domino condensation-hetero cyclization process, mediated by copper oxide nanoparticles under ligand-free conditions

A simple and highly practical method for the synthesis of 2-N-substituted benzothiazoles has been developed by using nanocopper oxide as a recyclable catalyst. The present tandem process allows to get access to a wide range of 2-N-substituted benzothiazoles in good to excellent yields by the reaction of 2-iodo aniline with carbon disulfide and piperidine in presence of KOH as a base and DMSO as a solvent under ligand-free conditions.

One-pot synthesis of 2-aminobenzothiazoles using a new reagent of [Bmim]Br3 in [Bmim]BF4

The one-pot direct synthesis of 2-aminobenzothiazoles from phenyl isothiocyanate and amines using a new reagent of 1-butyl-3-methylimidazolium tribromide ([Bmim]Br3) in ionic liquid 1-butyl-3-methyl-imidazolium tetraflouoroborate ([Bmim]BF4) is described.

Efficient Conversion of Substituted Aryl Thioureas to 2-Aminobenzothiazoles Using Benzyltrimethylammonium Tribromide

The reaction of molecular bromine (Br2) with arylthioureas is known to produce 2-aminobenzothiazoles (Hugerschoff reaction). We show here that benzyltrimethylammonium tribromide (1, PhCH2NMe 3Br3), a stable, crystalline organic ammonium tribromide (OATB), can be readily utilized as an alternative electrophilic bromine source. It is easier to control the stoichiometry of addition with an OATB, which minimizes aromatic bromination caused by excess reagent. We have developed a direct procedure from isothiocyanates and amines using tetrabutylammonium thiocyanate (Bu4NSCN) and PhCH2NMe3Br 3 to afford functionalized 2-aminobenzothiazoles.