A convenient oxidative cyclodesulfurization method toward the synthesis of benzofused nitrogen heterocycles using inexpensive and readily available potassium periodate as an oxidant was developed. Upon treating isothiocyanates with ortho-substituted anilines bearing N,N-, N,O-, and N,S-bis-nucleophiles, followed by an intramolecular cyclization of the in situ generated monothioureas, substituted 2-aminobenzazole
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–I2 system in the presence of triethylamine as a desulfurization agent, monothioureas prepared in situ from the reaction of bis-nucleophiles with isothiocyanates underwent rapid cyclization to afford a variety
Desymmetrisation of aromatic diamines and synthesis of non-symmetrical thiourea derivatives by click-mechanochemistry
作者:Vjekoslav Štrukil、Davor Margetić、Marina D. Igrc、Mirjana Eckert-Maksić、Tomislav Friščić
DOI:10.1039/c2cc34013e
日期:——
ortho- and para-Phenylenediamines were desymmetrised and quantitatively transformed into mono- and bis-(thio)ureas or mixed thiourea–ureas through a one-pot mechanochemical click reaction sequence; mechanochemical desymmetrisation proceeds quantitatively without excess reagents and allows the controlled extension of a molecular structure by combining normally competing reactions.
Simple urea/thiourea sensors for the biologically important ions
作者:Jongmin Kang、Ju Hoon Lee、Young Hee Kim、Sung kyu Lee、Eun Young Kim、Hong Gyu Lee、Cheal Kim
DOI:10.1007/s10847-010-9853-x
日期:2011.6
Two anion receptors 1 and 2 with a nitrophenyl group as a signaling group and urea/thiourea as a binding group were synthesized and their anion binding abilities were examined. The receptor 1 formed the hydrogen-bonded complex with various anions except fluoride. However, the receptor 2 immediately formed deprotonated receptor with various anions. Therefore, they operated based on a hydrogen bonding and an acid–base equilibrium. In addition, the receptor 1 proved to be an efficient and selective naked-eye detector for the fluoride ion.