7471-81-0Relevant academic research and scientific papers
Synthesis and Structure-Photophysics Evaluation of 2-N-Amino-quinazolines: Small Molecule Fluorophores for Solution and Solid State
Alayrac, Carole,Doan, Thu-Hong,Hibner-Kulicka, Paulina,Lohier, Jean-Francois,Lukarska, Malgorzata,Motoyama, Miho,Nanbu, Shinkoh,Otake, Ryo,Ozawa, Kota,Suzuki, Yumiko,Witulski, Bernhard
supporting information, p. 2087 - 2099 (2021/06/27)
2-N-aminoquinazolines were prepared by consecutive SNAr functionalization. X-ray structures display the nitrogen lone pair of the 2-N-morpholino group in conjugation with the electron deficient quinazoline core and thus representing electronic push-pull systems. 2-N-aminoquinazolines show a positive solvatochromism and are fluorescent in solution and in solid state with quantum yields up to 0.73. Increase in electron donor strength of the 2-amino substituent causes a red-shift of the intramolecular charge transfer (ICT) band (300–400 nm); whereas the photoluminescence emission maxima (350–450 nm) is also red-shifted significantly along with an enhancement in photoluminescence efficiency. HOMO-LUMO energies were estimated by a combination of electrochemical and photophysical methods and correlate well to those obtained by computational methods. ICT properties are theoretically attributed to an excitation to Rydberg-MO in SAC-CI method, which can be interpreted as n-π* excitation. 7-Amino-2-N-morpholino-4-methoxyquinazoline responds to acidic conditions with significant increases in photoluminescence intensity revealing a new turn-on/off fluorescence probe.
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.
Organocatalytic Visible Light Enabled SNAr of Heterocyclic Thiols: A Metal-Free Approach to 2-Aminobenzoxazoles and 4-Aminoquinazolines
Rattanangkool, Eakkaphon,Sukwattanasinitt, Mongkol,Wacharasindhu, Sumrit
, p. 13256 - 13262 (2017/12/26)
The direct amination reaction of heterocyclic thiols has been developed in the presence of the nonhazardous photocatalyst Rose Bengal under irradiation of visible light. The reaction provides a straightforward approach to pharmaceutically and synthetically useful 2-aminobenzoxazole and 4-aminoquinazoline derivatives from the corresponding heterocyclic thiols with amines in good to excellent yields. Our photochemical reaction can be successfully adapted into a continuous flow reactor which is applicable for large-scale chemical industry. The key benefits of this reaction include the use of metal-free, low-cost Rose Bengal catalyst and practical operation (ambient temperature, open flask, and undried solvents).
Amination of heteroaryl chlorides: Palladium catalysis or SNAr in green solvents?
Walsh, Katie,Sneddon, Helen F.,Moody, Christopher J.
, p. 1455 - 1460 (2013/09/12)
The reaction of heteroaryl chlorides in the pyrimidine, pyrazine and quinazoline series with amines in water in the presence of KF results in a facile SNAr reaction and N-arylation. The reaction is less satisfactory with pyridines unless an add
An efficient HCCP-mediated direct amination of quinazolin-4(3H)-ones
Shen, Zhenlu,He, Xiaofei,Dai, Jialiang,Mo, Weimin,Hu, Baoxiang,Sun, Nan,Hu, Xinquan
, p. 1665 - 1672 (2011/04/15)
An efficient direct amination of quinazolin-4(3H)-ones has been developed. Treatment of quinazolin-4(3H)-ones with HCCP, DIPEA, and N-contained nucleophiles in acetonitrile could be able to form the corresponding 4-aminoquinazoline derivatives. Under the
C-N bond formation by the oxidative alkylamination of azines: Comparison of AgPy2MnO4 versus KMnO4 as oxidant
Gulevskaya, Anna V.,Maes, Bert U. W.,Meyers, Caroline,Herrebout, Wouter A.,Van Der Veken, Benjamin J.
, p. 5305 - 5314 (2007/10/03)
Reports on the successful oxidative alkylamination of azines by the S NH-reaction, with the use of alkylamines other than methylamine, are very scarce. Hitherto, the experimental limitation to extend oxidative animation of azines wit
