Abstract
Reaction of l-methyl-3-methylthiomaleimides (1a-c) with N,N-dialkylanilines (2) under refluxing in acetic acid condition gave the corresponding 3-(4-diakylamino)phenyl-1-methylmaleimides (3a-g). Treatment of these 1-methyl-3-phenylmaleimides (3a, c) with Lawesson's reagent under refluxing in toluene afforded new blue dyes, 4-(4-dialkylamino)phenyl-3-cyano-1-methyl-5-oxopyrrole-2-thiones (5a, b) which are brilliant blue dyes appearing at 606 and 615 nm (log ε: 4.59 and 4.50) in UV spectra. Reaction of 4-methoxycarbonyl-1-methyl-3-methylthiomaleimide (1b) with 3-dialkylamino-phenol under the same reaction conditions gave cyclizcd products, 2H, 4H-[1]-benzopyrano[3,4-c]pyrrole-1,3,4-triones (6a-c) in good yields.
Original language | English |
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Pages (from-to) | 41-44 |
Number of pages | 4 |
Journal | Heterocycles |
Volume | 46 |
Issue number | 1 |
DOIs | |
Publication status | Published - Jan 1 1997 |
Externally published | Yes |
ASJC Scopus subject areas
- Analytical Chemistry
- Pharmacology
- Organic Chemistry