Transposition of Aromaticity from a Furan to a Cyclohexane Ring in Furoisoindoles During the Interaction of 3-(Furyl)allylamines with Bromomaleic Anhydride

• Published in: Synlett Vol. 31; no. 3; pp. 255 - 260
• Main Authors: Alekseeva, Kseniia A., Kvyatkovskaya, Elizaveta A., Nikitina, Eugeniya V., Zaytsev, Vladimir P., Eroshkina, Svetlana M., Shikhaliev, Khidmet S., Truong, Hieu H., Khrustalev, Victor N., Zubkov, Fedor I.
• Format: Journal Article
• Language: English
• Published: STUTTGART Thieme Medical Publishers 01.02.2020
• Subjects: Chemistry; Chemistry, Organic; Physical Sciences; Science & Technology; furan; ARYLATION; transposition of aromaticity; atom-efficient reaction; ALDOSE REDUCTASE INHIBITORS; ALDER; CONSTRUCTION; IMDAV reaction; Diels-Alder reaction; BOND; furo[2,3f]isoindole; DERIVATIVES; STRUCTURE REVISION
• ISSN: 0936-5214; 1437-2096
• DOI: 10.1055/s-0039-1690782

An unexpected four-step reaction sequence was discovered in the course of investigation of the interaction between 3-(furan-2-yl)allylamines and bromomaleic anhydride. This conversion begins with the initial N -acylation of the allylamines by the anhydride, followed by intramolecular Diels-Alder reaction, which is accompanied by a dehydrohalogenation, and ends with the formation of partially unsaturated furo[2,3- f ]isoindoles followed by transposition of aromaticity from the furan moiety to the neighboring cyclohexane ring. The reaction between 3-(furan-3-yl)allylamines and bromomaleic anhydride does not stop at a furo[2,3- f ]isoindole formation step, but proceeds further with the cleavage of the furan ring in a 100% atom-efficient fashion to provide polysubstituted isoindoline-4-carboxylic acids.