One pot preparation of pyrido[2,3,4-de]quinazolines and benzo[de][1,6]naphthyridines by a consecutive process involving an aza-Wittig/electrocyclic ring-closure/heterocumulene-mediated annelation or intramolecular Diels-Alder cycloaddition sequence.
作者:Pedro Molina、Mateo Alajarín、Angel Vidal
DOI:10.1016/s0040-4039(00)92391-8
日期:1991.9
Wittig-type reaction of bis(iminophosphorane)1 with one mole of isocyanate leads to the iminophosphoranes 5 which by treatment with a second mole of isocyanate afforded pyrido[2,3,4-de]quinazolines 6. Similarly, reaction with ketenes leads to the formation of benzo[de][1,6]naphthyridines 9. Direct conversion 1→6 and 1→9 were achieved using two moles of isocyanate or ketene respectively.
双(亚氨基正膦)1与一摩尔异氰酸酯的Aza Wittig型反应产生亚氨基正膦5,其通过用第二摩尔异氰酸酯处理得到吡啶并[2,3,4-de]喹唑啉6。类似地,与乙烯酮的反应导致形成苯并[de] [1,6]萘啶9。分别使用两摩尔的异氰酸酯或乙烯酮可实现1 → 6和1 → 9的直接转化。