La[N(SiMe3)2]3 proves to be an efficient catalyst system for the cyclocarbonylation of 1,2-disubstituted benzenes with isocyanates. In this approach, aryl/alkyl isocyanates react with o-phenylenediamine, o-aminophenol...La[N(SiMe3)2]3 proves to be an efficient catalyst system for the cyclocarbonylation of 1,2-disubstituted benzenes with isocyanates. In this approach, aryl/alkyl isocyanates react with o-phenylenediamine, o-aminophenol, o-aminothiophenol, catechols and anilines ortho-substituted by CH2NH2 and CONH2 to form, respectively, the corresponding benzimidazolones, benzoxazolones, benzothiazolones, benzodioxolones, 3,4-dihydroquinazolin-2(1H)-one, and quinazolinediones. These results represent the first example of lanthanide-catalyzed carbonylation. This methodology is also applicable for the preparation of various benzannulated 1,3-diheteroatom cyclic thioketones starting from aryl/alkyl isothiocyanates or CS2 in good to excellent yields. Based on the results of experiments performed using an o-aminobenzamido dianion lanthanide complex, a general mechanism, involving the tandem reaction of two lanthanide-ligand bonds with one heterocumulene molecule, is proposed as well.展开更多
A new six-membered heterocyclic compound including four nitrogen atoms was obtained. The compound [NH 3(CH 2) 2NH(CH 2CH 2) 2NH(CH 2) 2NH 3]·(ClO 4) 4·4H 2O was characterized by X-ray single crystal diffract...A new six-membered heterocyclic compound including four nitrogen atoms was obtained. The compound [NH 3(CH 2) 2NH(CH 2CH 2) 2NH(CH 2) 2NH 3]·(ClO 4) 4·4H 2O was characterized by X-ray single crystal diffraction,elemental analysis,IR, 1H NMR and MS. It belongs to a monoclinic system,\{ P2 1/n \},with a =0.787 34(7) nm, b =1.966 98(18) nm, c =0.820 75(8) nm, β =103.396(2)° and \{ Z =\}2. The molecular structure consists of six-membered heterocyclic NH 3(CH 2) 2NH(CH 2CH 2) 2NH(CH 2) 2NH 3,ClO - 4 and H 2O. The six-membered heterocyclic is a stable chair conformation. Various hydrogen bonds are formed among nitrogen atoms,ClO - 4 anion and water molecules. This compound may be a better heterocyclic ligand containing four nitrogon atoms,which can perhaps be employed to aggregate with transitional metal atoms and generate new complexes.展开更多
基金supported by the National Natural Science Foundation of China (21132002, 21272038)the National Basic Research Program of China (2011CB825300)
文摘La[N(SiMe3)2]3 proves to be an efficient catalyst system for the cyclocarbonylation of 1,2-disubstituted benzenes with isocyanates. In this approach, aryl/alkyl isocyanates react with o-phenylenediamine, o-aminophenol, o-aminothiophenol, catechols and anilines ortho-substituted by CH2NH2 and CONH2 to form, respectively, the corresponding benzimidazolones, benzoxazolones, benzothiazolones, benzodioxolones, 3,4-dihydroquinazolin-2(1H)-one, and quinazolinediones. These results represent the first example of lanthanide-catalyzed carbonylation. This methodology is also applicable for the preparation of various benzannulated 1,3-diheteroatom cyclic thioketones starting from aryl/alkyl isothiocyanates or CS2 in good to excellent yields. Based on the results of experiments performed using an o-aminobenzamido dianion lanthanide complex, a general mechanism, involving the tandem reaction of two lanthanide-ligand bonds with one heterocumulene molecule, is proposed as well.
文摘A new six-membered heterocyclic compound including four nitrogen atoms was obtained. The compound [NH 3(CH 2) 2NH(CH 2CH 2) 2NH(CH 2) 2NH 3]·(ClO 4) 4·4H 2O was characterized by X-ray single crystal diffraction,elemental analysis,IR, 1H NMR and MS. It belongs to a monoclinic system,\{ P2 1/n \},with a =0.787 34(7) nm, b =1.966 98(18) nm, c =0.820 75(8) nm, β =103.396(2)° and \{ Z =\}2. The molecular structure consists of six-membered heterocyclic NH 3(CH 2) 2NH(CH 2CH 2) 2NH(CH 2) 2NH 3,ClO - 4 and H 2O. The six-membered heterocyclic is a stable chair conformation. Various hydrogen bonds are formed among nitrogen atoms,ClO - 4 anion and water molecules. This compound may be a better heterocyclic ligand containing four nitrogon atoms,which can perhaps be employed to aggregate with transitional metal atoms and generate new complexes.
