All these products possess a keto group which will allow further transformations. The same concept was applied for the synthesis of the S-shaped terpyridine 25. The reaction of the Mannich base 21 with 1,3-cyclohexanedione yielded the heptacyclicterpyridine 22, which is a key intermediate for the synthesis of torands and other tridentate clefts. The ketone 12a was used for the synthesis of the quaterpyridine
Alumina-sulfuric acid catalyzed eco-friendly synthesis of xanthenediones
作者:Amit Pramanik、Sanjay Bhar
DOI:10.1016/j.catcom.2011.12.036
日期:2012.4
Alumina-sulfuric acid has been developed as a cost-effective, recyclable, heterogeneous solid acid catalyst for the eco-friendly synthesis of 9-aryl-1,8-dioxododecahydroxanthenes and 9-aryl-3,3,6,6-tetramethyl-1,8-dioxooctahydroxanthenes through the condensation of cyclic 1,3-diketones with different aryl and heteroaryl aldehydes. (C) 2012 Elsevier BM. All rights reserved.