Synthetic studies related to diketopyrrolopyrrole (DPP) pigments. Part 2: The use of esters in place of nitriles in standard DPP syntheses: Claisen-type acylations and furopyrrole intermediates
作者:Colin J.H. Morton、Richard L. Riggs、David M. Smith、Nicholas J. Westwood、Philip Lightfoot、Alexandra M.Z. Slawin
DOI:10.1016/j.tet.2004.10.027
日期:2005.1
Ethyl 2-aryl-4,5-dihydro-5-oxopyrrole-3-carboxylates react with esters or acyl halides in the presence of a strong base to give 4-acyl derivatives, which exist predominantly as either E- or Z-enols. These are cyclised, either in solution at temperatures >200 °C or by microwave irradiation, to 3,6-disubstituted 1H-furo[3,4-c]pyrrolediones which, after N-protection, are convertible by reaction with primary
2-芳基-4,5-二氢-5-氧杂吡咯-3-羧酸乙酯在强碱的存在下与酯或酰基卤反应,生成4-酰基衍生物,其主要以E-或Z-烯醇形式存在。将它们在温度> 200°C的溶液中或通过微波辐射环化成3,6-二取代的1 H-呋喃[3,4- c ]吡咯二酮,在N-保护后可通过与伯胺反应转化合成新的N,N'-二取代的DPP衍生物。