61350-45-6Relevant academic research and scientific papers
Reactions of Cyclic Oxalyl Compounds, XXIII. Reactions of Five-membered 2,3-Dioxo Heterocycles with Carbodiimides - a Synthetic Pathway to Hetero Analogues of Deazapurine Systems
Kollenz, Gert,Penn, Gerhard,Ott, Walter,Peters, Karl,Peters, Eva-Maria,et al.
, p. 1310 - 1329 (2007/10/02)
The furandione 1 reacts with diaryl- or arylalkylcarbodiimides to yield 4--2,3-furandiones 5, which isomerize to 2,3-pyrrolediones 2 above 60 deg C. 1, 2, and 5 react with dimethylcarbodiimide under mild conditions (20 deg C, a few minutes) to give the so far unknown pyrrolooxazinediones 7 which reversibly can lose dimethylcarbodiimide to form again 2.Analogously 2,3-thiophenedione 3 and dimethyl- or diisopropylcarbodiimide yield the pyrrolothiazines 8.The basic skeletons of 7 and 8 were determined by X-ray structure analys is of 7a and 8b.On the other hand, the reaction of 1 with diethyl- or diisopropylcarbodiimide leads to furopyrimidines 10.The bicyclic compounds 7, 8, and 10 can be regarded as heteroanalogues of the 7-deazapurine system.The reaction pathways leading to 5, 7, 8, and 10 involve cycloadditions, cycloreversions or fragmentation reactions as well as some surprising new furandione-furandione rearrangements.
