One or Two-Step Bohlmann-Rahtz Heteroannulation of 6-Aminouracil Derivatives for the Synthesis of Pyrido[2,3-<i>d</i>]pyrimidines
作者:Mark C. Bagley、David D. Hughes
DOI:10.1055/s-2002-32953
日期:——
The Michael addition-cyclodehydration of a 6-aminouracil and alkynone proceeds to give 5-deazapterin derivatives with total control of regiochemistry. This simple and facile cyclocondensation process is catalyzed by zinc(II) bromide or ytterbium(III) trifluoromethanesulfonate at 110 °C, providing the heteroannulated products in up to 94% yield.
6-氨基尿嘧啶和炔酮的迈克尔加成环脱水反应得到完全控制区域化学的5-去氮杂蝶呤衍生物。这种简单易行的环缩合反应由溴化锌 (II) 或三氟甲磺酸镱 (III) 在 110 °C 催化,以高达 94% 的产率提供杂环化产物。
Studies on Condensed Pyrimidine Systems. XIX. A New Synthesis of Pyrido [2,3-d] pyrimidines. The Condensation of 1,3-Diketones and 3-Ketoaldehydes with 4-Aminopyrimidines
作者:Roland K. Robins、George H. Hitchings
DOI:10.1021/ja01546a061
日期:1958.7
Ionic liquid promoted synthesis of heterocycle-fused pyrimidine-2,4(1H,3H)-diones utilising CO2
An efficient ionic liquid system was developed for the preparation of various heterocycle-fused pyrimidine-2, 4(1H,3H)-diones in moderate to excellent yields (52-95%). It was found that [HDBN+][TFE-], a simple and easily prepared ionic liquid, could act as both the solvent and reaction promoter, and that the reactions could be efficiently carried out at atmospheric pressures of CO2. (C) 2018 Elsevier Ltd. All rights reserved.
Ridi; Checchi, Annali di Chimica, 1957, vol. 47, p. 728,737