Rapid, efficient and solvent-free synthesis of (un)symmetrical xanthenes catalyzed by recyclable sulfated polyborate
作者:Manisha S. Patil、Amey V. Palav、Chetan K. Khatri、Ganesh U. Chaturbhuj
DOI:10.1016/j.tetlet.2017.06.027
日期:2017.7
straightforward approach to the synthesis of 1,8-dioxo-octahydroxanthenes, 14-phenyl-14H-dibenzo[a,j]xanthene and tetrahydrobenzoxanthene-11-ones under solvent-free conditions usingsulfated polyborate as a highly efficientcatalyst. The procedure offers several advantages including cleaner reaction profile, mild reaction condition, economic, recyclable and environmentally benign catalyst, high yields, simple
Convenient synthesis of novel 2,2-dialkyl-1,2-dihydronaphtho[2,1-b]furans
作者:Doug Vaughan、Amitabh Jha
DOI:10.1016/j.tetlet.2009.07.087
日期:2009.10
2,2-dialkylacetaldehydes with electron-rich 2-naphthols in presence of p-TSA under closed-vessel solvent-free microwave irradiation conditions resulted in formation of corresponding dihydronaphtho[2,1-b]furans in good to excellent yields. In several cases, small amounts of 14-alkyl-14H-dibenzo[a,j]xanthenes were also formed.
2,2-二烷基乙醛与p -TSA存在下的富电子2-萘在密闭容器无溶剂微波辐射条件下反应,可形成相应的二氢萘[2,1- b ]呋喃,收率高至优异。在几种情况下,还形成了少量的14-烷基-14 H-二苯并[ a,j ]蒽。
An efficient, high yielding, and eco-friendly method for the synthesis of 14-aryl- or 14-alkyl-14H-dibenzo[a,j]xanthenes using polyvinylsulfonic acid as a recyclable Brønsted acid catalyst
作者:Ali Rahmatpour
DOI:10.1007/s00706-011-0537-z
日期:2011.12
Aryl or alkyl-14H-dibenzo[a,j]xanthene derivatives were synthesized efficiently by the reaction of 2-naphthol and aromatic or aliphatic aldehydes in the presence of polyvinylsulfonic acid (PVSA) as a reusable Bronsted acid catalyst under aqueous conditions at 90 A degrees C. This reaction was studied under different conditions, and several solvents were examined. In terms of reaction yield and time, water was found to be the optimum solvent. The catalytic performance of PVSA was then compared with various acidic catalysts under optimized reaction conditions. The catalyst is well characterized using IR and DSC techniques.