The intramolecular Diels-Alder vinylthiophen (IMDAV) reaction: An easy approach to thieno[2, 3-f]isoindole-4-carboxylic acids. Issue 43 (25th October 2017)

• Record Type: Journal Article
• Authors: Horak, Yuriy I.; Lytvyn, Roman Z.; Laba, Yevhen-Oleh V.; Homza, Yuriy V.; Zaytsev, Vladimir P.; Nadirova, Maryana A.; Nikanorova, Tatiana V.; Zubkov, Fedor I.; Varlamov, Alexey V.; Obushak, Mykola D.
• Is Part Of: Tetrahedron letters. Volume 58:Issue 43(2017)
• Page Start: 4103
• Page End: 4106
• Publication Date: 2017-10-25
• Subjects: Vinylthiophene -- [4+2] cycloaddition -- Intramolecular Diels-Alder reaction -- IMDAV reaction -- Thieno[2, 3-f]isoindoles -- Thiophene; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2017.09.038
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Highlights: Application of the IMDAV strategy in synthesis of thieno[2, 3- f ]isoindoles. Mild and diastereoselective synthesis of thieno[2, 3- f ]isoindole-4-carboxylic acids. Reaction of 3-thienylallylamines with maleic anhydride gives thieno[2, 3- f ]isoindoles. Abstract: The reaction of readily accessible 3-(thien-2-yl)allylamines with maleic anhydride, followed by a domino sequence involving successive acylation/[4+2] cycloaddition steps, leads to the formation of the thieno[2, 3- f ]isoindole core. The key step, the intramolecular Diels-Alder vinylaren (IMDAV) reaction, proceeds with high level of diastereoselectivity and with formation of a single diastereoisomer of the target product 4, 4a, 5, 6, 7, 7a-hexahydro-3a H -thieno[2, 3- f ]isoindole-4-carboxylic acids in excellent yields. If the reaction is carried out at room temperature, it occurs in 2–3 days and the proton migration ( H -shift) does not take place at the last stage. In boiling benzene, the reaction is complete after three hours, but in this case a slight impurity of byproducts bearing aromatic thiophene ring – 4a, 5, 6, 7, 7a, 8-hexahydro-4 H -thieno[2, 3- f ]isoindole-4-carboxylic acids is formed.