15175-39-0Relevant academic research and scientific papers
Microwave-Enhanced On-Water Amination of 2-Mercaptobenzoxazoles to Prepare 2-Aminobenzoxazoles
Tankam, Theeranon,Srisa, Jakkrit,Sukwattanasinitt, Mongkol,Wacharasindhu, Sumrit
, p. 11936 - 11943 (2018/10/02)
In this work, we developed a catalyst-free amination of 2-mercaptobenzoxazoles on water under microwave irradiation. The product, 2-aminobenzoxazoles, was successfully produced via direct amination with various amines in moderate to high yields. The formal synthesis of Suvorexant, a medication for the treatment of insomnia, was accomplished using a developed amination process. The reaction was completed in an hour at 100-150 °C in a microwave reactor without the use of external catalyst or additive. Key benefits of this process include an on-water reaction, short reaction time, being scalable and catalyst-free, and use of 2-mercaptobenzoxazoles as an inexpensive starting material having low environmental impact in its preparation.
One-pot reaction for the synthesis of N-substituted 2-aminobenzoxazoles using triphenylbismuth dichloride as cyclodesulfurization reagent
Murata, Yuki,Matsumoto, Natsuho,Miyata, Maya,Kitamura, Yuki,Kakusawa, Naoki,Matsumura, Mio,Yasuike, Shuji
, p. 18 - 23 (2018/02/09)
The treatment of various 2-aminophenols with isothiocyanates afforded thioureas, which were reacted in situ with triphenylbismuth dichloride in the presence of triethylamine to give the expected N-substituted benzoxazol-2-amines in good to excellent yields. Triphenylbismuth dichloride promoted the successful cyclodesulfurization of thioureas with short reaction times under mild reaction conditions. This reaction is the first example of the synthesis of heterocyclic rings using a pentavalent organobismuth reagent.
Ultrasound-assisted synthesis of substituted 2-aminobenzimidazoles, 2-aminobenzoxazoles, and related heterocycles
Phakhodee, Wong,Duangkamol, Chuthamat,Wiriya, Nittaya,Pattarawarapan, Mookda
supporting information, p. 5290 - 5293 (2016/11/11)
A sonochemical method for the synthesis of 2-aminobenzimidazoles and 2-aminobenzoxazoles, as well as chiral aminooxazolines and a chiral substituted quinazolin-5-one is reported. Using the Ph3P–I2system in the presence of triethylami
Highly efficient one-pot synthesis of 2-aminobenzoxazoles using triflic acid as a cyclodesulfurizing reagent
Khatik, Gopal L.,Dube, Namita,Pal, Anang,Nair, Vipin A.
experimental part, p. 2631 - 2639 (2011/08/07)
An efficient one-pot synthetic strategy for 2-aminobenzoxazoles was developed from isothiocyanates and 2-aminophenol using triflic acid as a cyclodesulfurizing reagent. Taylor & Francis Group, LLC.
One-pot synthesis of five and six membered N, O, S-heterocycles using a ditribromide reagent
Yella, Ramesh,Patel, Bhisma K.
experimental part, p. 754 - 763 (2010/11/03)
In a one-pot procedure, bromine less brominating reagent 1,1′-(ethane-1,2-diyl)dipyridinium bistribromide (EDPBT) has been utilized as an efficient desulfurizing agent for the construction of a library of heterocycles containing N, O, and S starting from aryl/alkyl isothiocyanates. In this approach, aryl/alkyl isothiocyanate reacts with o-phenylenediamine (o-PD), o-aminophenol, and o-aminothiophenol to form their monothiourea which on desulfurization with EDPBT led to the formation of corresponding 2-aminobenzimidazoles, 2-aminobenzoxazoles, and 2-aminobenzothiazoles, respectively. An interesting regioselectivity was observed for unsymmetrical thiourea having a naphthyl moiety on the one side and an ortho amino or an ortho hydroxy phenyl group on the other side giving a completely different product which is mainly dependent on the nature of the nucleophiles (-OH or -NH 2). Further, the bis-thioureas resulted from the aliphatic 1,2-diamine with 2 equiv of aryl isothiocyanates on treatment with EDPBT gave imidazolidenecarbothioamides, whereas bis-thioureas resulted from aromatic 1,2-diamine yielded benzimidazoles with concurrent expulsion of an isothiocyanate unit. This method is simple and applied to various substrates which are amenable to bromination that reveals the desulfurizing ability of EDPBT predominating over its brominating ability. Finally, the spent reagent EDPDB can be recovered, regenerated, and reused without any loss of activity.
