1334474-19-9Relevant academic research and scientific papers
Silica sulfuric acid: A reusable solid catalyst for one pot synthesis of densely substituted pyrrole-fused isocoumarins under solvent-free conditions
Pathak, Sudipta,Debnath, Kamalesh,Pramanik, Animesh
, p. 2344 - 2353 (2014/01/06)
A convenient and efficient methodology for the synthesis of densely substituted pyrrole-fused isocoumarins, which employs solidsupported silica sulfuric acid (SSA) as catalyst, has been developed. When the mixture of ninhydrin adducts of acetylacetone/ethyl acetoacetate and primary amines was heated on the solid surface of SSA under solvent-free conditions, the pyrrole-fused isocoumarins were formed in good yields. This synthetic method has several advantages such as the employment of solvent-free reaction conditions without the use of any toxic reagents and metal catalysts, the ease of product isolation, the use of a recyclable catalyst, the low cost, the easy availability of the starting materials, and the excellent yields of products.
Facile synthesis of substituted pyrrole-fused isocoumarins from ninhydrin
Pathak, Sudipta,Kundu, Ashis,Pramanik, Animesh
, p. 5180 - 5183 (2011/10/12)
A simple and efficient procedure has been developed for the synthesis of substituted pyrrole-fused isocoumarins from easily available ninhydrin. The cyclic hemiaminal dihydroxy-indenopyrroles, the adducts of ninhydrin with enamines of acetylacetone, give pyrrole-fused isocoumarins upon heating in acidic medium. The process constitutes an interesting acid-catalyzed rearrangement to eight-membered lactams followed by intramolecular cyclization involving the amino and keto groups.
