6344-76-9Relevant academic research and scientific papers
Hexachlorocyclotriphosphazene (HCCP)-mediated direct formation of thioethers and ethers from quinazolin-4(3H)-ones
Hu, Baoxiang,Zhang, Xiaochu,Sheng, Lili,Guo, Ming,Shen, Zhenlu,Hu, Xinquan,Sun, Nan,Mo, Weimin
, p. 5580 - 5593 (2013/07/04)
A hexachlorocyclotriphosphazene (HCCP)-mediated direct formation of quinazoline (thio)ethers from quinazolin-4(3H)-ones has been developed. Treatment of quinazolin-4(3H)-ones with HCCP, diisopropylethylamine (DIPEA), and thiophenols resulted in formation of the corresponding 4-arylthioquinazoline derivatives in moderate to excellent yields. This method has also been utilized to prepare 4-aryloxyquinazoline and 4-alkoxyquinazoline derivatives using phenols and sodium alkoxides as the nucleophiles.
The scope and mechanism of phosphonium-mediated SNAr reactions in heterocyclic amides and ureas
Wan, Zhao-Kui,Wacharasindhu, Sumrit,Levins, Christopher G.,Lin, Melissa,Tabei, Keiko,Mansour, Tarek S.
, p. 10194 - 10210 (2008/04/12)
(Chemical Equation Presented) An efficient "one-step" synthesis of cyclic amidines and guanidines has been developed. Treatment of cyclic amides and ureas with benzotriazol-l-yloxytris(dimethylamino)phosphonium hexafluorophosphate (BOP), base, and nitrogen nucleophiles leads to the formation of the corresponding cyclic amidines and guanidines, typically in good to excellent yields. This method has also been used to prepare heteroaryl ethers and thioethers using phenol and thiophenol nucleophiles. Time course NMR and HPLC-MS studies have facilitated explicit characterization of the proposed intermediates (the phosphonium salt and HOBt adduct); the data reveal a stepwise reaction pathway.
An efficient direct amination of cyclic amides and cyclic ureas
Wan, Zhao-Kui,Wacharasindhu, Sumrit,Binnun, Eva,Mansour, Tarek
, p. 2425 - 2428 (2007/10/03)
An efficient one-step amination of cyclic amides and ureas has been developed. Treatment of cyclic amides and cyclic ureas with BOP in the presence of DBU in various solvents led to the formation of cyclic amidines and cyclic guanidines in good to excellent yields. Concise syntheses of biologically intriguing kinetin and potent kinase inhibitor olomoucin were thus achieved in just one and two steps, respectively.
Synthesis of alkylthio- and arylthioheteroarenes by regioselective grignard reaction of thiocyanatoheteroarenes
Nagasaki, Izuru,Matsumoto, Miyuki,Yamashita, Masanori,Miyashita, Akira
, p. 1015 - 1024 (2007/10/03)
Treatment of thiocyanatoheteroarenes (1) with Grignard reagents (2) afforded alkylthio- or arylthioheteroarenes (3-6) in good yields. Grignard reagents regioselectively attacked the sulfur atom of the thiocyanato group owing to the metal-chelating effect of this group in combination with the hetero ring-nitrogen. 2-Thiocyanatopyridine (1a), 2-thiocyanatopyrimidine (1b), 2-thiocyanatobenzothiazole (1c), and 4-thiocyanatoquinazoline (1d) were converted into a variety of sulfides. Sulfides consisting of two heteroarenes linked by a sulfur atom were readily obtained by this method.
NUCLEOPHILIC HETEROAROMATIC SUBSTITUTIONS. XLI. THE REACTION OF 4-PHENOXY- AND 4-PHENYLTHIO-QUINAZOLINE WITH PIPERIDINE IN ISOOCTANE: peri EFFECT ON BIFUNCTIONAL CATALYSIS
Corvi, Doretta,Mitidieri-Costanza, Angela,Sleiter, Giancarlo
, p. 167 - 172 (2007/10/02)
The kinetics of the piperidino dephenoxylation of 4-phenoxyquinazoline in isooctane have been followed spectrophotometrically.The reaction turned out to be not catalysed by piperidine and to be moderately speeded up by added 2-piperidone.The kinetic ineffectiveness of piperidine is explained by a steric effect of the peri-hydrogen atom, which makes the formation of a six-membered transition state impossible.The results of a kinetic study of the piperidino dethiophenoxylation of 4-phenylthioquinazoline confirm the insensitiveness of heteroaromatic substrates with sulphur-leaving groups to both base and bifunctional catalysis.
