通过用H 2 O 2-钨酸四氢喹唑啉氧化制备喹唑啉-1-氧化物,并研究了它们的环境光化学性质。报道了在光化学和热条件下,取代基对其光化学环化的影响以及产物1a H- [1,2]恶二叠氮化物[2,3- a ]喹唑啉的反应。喹唑啉-1-氧化物的环化和1a H- [1,2]恶嗪烯丙并[2,3- a ]喹唑啉的反应显示出明显的溶剂同位素和溶剂效应。
Synthesis of 2-aryl-1,2,3,4-tetrahydroquinazolin-1-ols and their conversion to 7-aryl-9H-6-oxa-5,8-diaza-benzocycloheptenes
摘要:
2-Aminobenzylamine was reacted with corresponding aromatic or heteroaromatic aldehydes to give 1,2,3,4-tetrahydroquinazolines 1 the oxidation of which with H2O2-tungstate in methanol led to the formation of the corresponding 1,2,3,4-tetrahydroquinazolin-1-ols 2. A one-pot procedure involving the treatment of the in situ formed quinazoline 1 with H2O-tungstate again led to the formation of 2. Compounds 2 react with 2equiv of aryl isocyanate in toluene at room temperature to produce compounds 3. The probable mechanism of the ring-expanding carbamoylation of quinazolin-1-ols 2 to 6-oxa-5,8-diaza-benzocycloheptenes 3 is discussed. (C) 2004 Elsevier Ltd. All rights reserved.
A new regioselective synthesis and ambient light photochemistry of quinazolin-1-oxides
作者:Necdet Coşkun、Meliha Çetin
DOI:10.1016/j.tet.2007.02.004
日期:2007.4
their ambient light photochemistry was investigated. Substituenteffects on their photochemical cyclization and the reactions of the products 1aH-[1,2]oxazireno[2,3-a]quinazolines under photochemical and thermal conditions are reported. The cyclization of quinazolin-1-oxides and the reactions of 1aH-[1,2]oxazireno[2,3-a]quinazolines show pronounced solvent isotope and solvent effects.
通过用H 2 O 2-钨酸四氢喹唑啉氧化制备喹唑啉-1-氧化物,并研究了它们的环境光化学性质。报道了在光化学和热条件下,取代基对其光化学环化的影响以及产物1a H- [1,2]恶二叠氮化物[2,3- a ]喹唑啉的反应。喹唑啉-1-氧化物的环化和1a H- [1,2]恶嗪烯丙并[2,3- a ]喹唑啉的反应显示出明显的溶剂同位素和溶剂效应。
Synthesis of 2-aryl-1,2,3,4-tetrahydroquinazolin-1-ols and their conversion to 7-aryl-9H-6-oxa-5,8-diaza-benzocycloheptenes
作者:Necdet Coşkun、Meliha Çetin
DOI:10.1016/j.tetlet.2004.10.062
日期:2004.11
2-Aminobenzylamine was reacted with corresponding aromatic or heteroaromatic aldehydes to give 1,2,3,4-tetrahydroquinazolines 1 the oxidation of which with H2O2-tungstate in methanol led to the formation of the corresponding 1,2,3,4-tetrahydroquinazolin-1-ols 2. A one-pot procedure involving the treatment of the in situ formed quinazoline 1 with H2O-tungstate again led to the formation of 2. Compounds 2 react with 2equiv of aryl isocyanate in toluene at room temperature to produce compounds 3. The probable mechanism of the ring-expanding carbamoylation of quinazolin-1-ols 2 to 6-oxa-5,8-diaza-benzocycloheptenes 3 is discussed. (C) 2004 Elsevier Ltd. All rights reserved.