Synthesis of 5H-Pyrazino[2,3-b]indoles from Indole-2,3-dione Derivatives.
摘要:
Reaction of N-acetylindol-2,3-diones with ethylenediamines gave the dihydro-pyrazinones 11, which could, after dehydrogenation and deacetylation be transformed to the corresponding 5H-pyrazino[2,3-b]indoles 5. N,N-Dimethylaminoethylation of the anion of 5 occurred selectively in the 5-position. Thermolysis of 1-pyrazinylbenzotriazole gave pyrazino[1,2-a]-benzimidazole 33 and no 5H-pyrazino[2,3-b] indole.
N,N′-(Phenylmethylene)diacetamide Analogues as Economical and Efficient Ligands in Copper-Catalyzed Arylation of Aromatic Nitrogen-Containing Heterocycles
TBAF-Assisted Copper-Catalyzed <i>N</i>-Arylation and Benzylation of Benzazoles with Aryl and Benzyl Halides under the Ligand/Base/ Solvent-Free Conditions
TBAF-assisted N-arylation and benzylation of benzazoles such as I H-benzimidazole, 1H-indole, and 1H-benzotriazole with aryl and benzyl halides have been demonstrated tinder the ligand/base/solvent-free conditions. In the presence of CuBr2 and TBAF (n-Bu4NF), the azoles underwent N-arylation and benzylation with aryl and benzyl halides smoothly in moderate to good yields. It is noteworthy that the reaction is conducted under the ligand/base/solvent-free conditions.