Polycyclic Aromatic Heterocycles with a Benzo[c][1, 2]azaborinine Core. (20th August 2019)

• Record Type: Journal Article
• Authors: de Lescure, Louis R.; Jesse, Talitha; Groziak, Michael P.; Powers, Xian B.; Olmstead, Marilyn M.
• Is Part Of: Journal of heterocyclic chemistry. Volume 56:Number 10(2019)
• Page Start: 2960
• Page End: 2965
• Publication Date: 2019-08-20
• Subjects: Heterocyclic compounds -- Periodicals; 547.59
• DOI: 10.1002/jhet.3651
• Languages: English
• ISSNs: 0022-152X

Abstract

Abstract : 2‐Formylphenylboronic acid condenses with active methylene reagents like α‐amino esters, ketones, and lactams directly to give benzo‐fused 1‐hydroxy‐2, 1‐azaborines in good yields within minutes under microwave‐accelerated conditions. The new stable boron heterocycles prepared to demonstrate this approach were characterized by NMR spectroscopy. Three members of a new diboron heteropentacyclic ring system, 5a, 12a‐diaza‐5, 12‐dibora‐5, 12‐dihydroxypentacene‐6, 13‐dione, were prepared, and one of these highly fluorescent compounds was characterized by X‐ray crystallography. Some key solid‐state structural features revealed by the X‐ray analysis provide a basis for explaining the limited solubility of these pentaheterocycles in common organic solvents. Abstract :