New methodology for the preparation of quinazoline derivatives via tandem aza-wittig/heterocumulene-mediated annulation. Synthesis of 4(3H)-quinazolinones, benzimidazo[1,2-c] quinazolines, quinazolino[3,2-a]quinazolines and benzothiazolo[3,2-c]quinazolines
作者:Pedro Molina、Mateo Alajarín、Angel Vidal
DOI:10.1016/s0040-4020(01)81321-1
日期:1989.1
2-substituted-4(3H)-quinazolinones . Iminophosphoranes also react with carbon disulfide and carbon dioxide to give the quinazolinones and respectively. Iminophosphorane , derived from 2-(o-azidophenyl)benzimidazole, reacts with isocyanates, carbon disulfide and carbon dioxide to form 6-substituted benzimidazo[1,2-c]quinazolines and respectively. In benzene at room temperature, iminophosphorane , reacts
Tandem Pseudopericyclic Reactions: [1,5]-X Sigmatropic Shift/6π-Electrocyclic Ring Closure Converting <i>N</i>-(2-X-Carbonyl)phenyl Ketenimines into 2-X-Quinolin-4(3<i>H</i>)-ones
tube in the absence of solvent. The mechanism for the conversion of these ketenimines into quinolin-4(3H)-ones has been studied by ab initio and DFT calculations, using as model compounds N-(2-X-carbonyl)vinyl ketenimines bearing different X groups (X = F, Cl, OH, SH, NH2, and PH2) converting into 4(3H)-pyridones. This computational study afforded two general reaction pathways for the first step of the