The Use of Aryl-Substituted Homophthalic Anhydrides in the Castagnoli-Cushman Reaction Provides Access to Novel Tetrahydroisoquinolone Carboxylic Acid Bearing an All-Carbon Quaternary Stereogenic Center

Nazar Moshnenko; Alexander Kazantsev; Olga Bakulina; Dmitry Dar'in; Mikhail Krasavin

doi:10.3390/molecules27238462

The Use of Aryl-Substituted Homophthalic Anhydrides in the Castagnoli-Cushman Reaction Provides Access to Novel Tetrahydroisoquinolone Carboxylic Acid Bearing an All-Carbon Quaternary Stereogenic Center

Molecules. 2022 Dec 2;27(23):8462. doi: 10.3390/molecules27238462.

Authors

Nazar Moshnenko¹, Alexander Kazantsev¹, Olga Bakulina¹, Dmitry Dar'in¹, Mikhail Krasavin^{1

2}

Affiliations

¹ Institute of Chemistry, Saint Petersburg State University, 26 Universitetskii Prospect, 198504 Peterhof, Russia.
² Institute of Living Systems, Immanuel Kant Baltic Federal University, 236041 Kaliningrad, Russia.

Abstract

Novel aryl-substituted homophthalic acids were cyclodehydrated to the respective homophthalic anhydrides for use in the Castagnoli-Cushman reaction. With a range of imines, this reaction proceeded smoothly and delivered hitherto undescribed 4-aryl-substituted tetrahydroisoquinolonic acids with remarkable diastereoselectivity, good yields and no need for chromatographic purification. These findings significantly extend the range of cyclic anhydrides employable in the Castagnoli-Cushman reaction and signify access to a novel substitution pattern around the medicinally relevant tetrahydroisoquinolonic acid scaffold.

Keywords: Castagnoli–Cushman reaction; all-carbon quaternary atom; homophthalic anhydride; imine; lactam; tetrahydroisoquinolone.

MeSH terms

Anhydrides* / chemistry
Carbon
Carboxylic Acids*
Imines / chemistry
Molecular Structure

Substances

Anhydrides
Carboxylic Acids
Carbon
Imines

Abstract

MeSH terms

Substances

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