Preparation of 2-phospholene oxides by the isomerization of 3-phospholene oxides

• Main Authors: Péter Bagi, Réka Herbay, Nikolett Péczka, Zoltán Mucsi, István Timári, and György Keglevich
• Format: Article
• Language: English
• Published: Beilstein-Institut 2020-04-01
• Series: Beilstein Journal of Organic Chemistry
• Subjects: chlorophosphonium salts; isomerization; 2-phospholene oxides; 3-phospholene oxides; quantum chemistry
• Online Access: https://doi.org/10.3762/bjoc.16.75
• ISSN: 1860-5397

A series of 1-substituted-3-methyl-2-phospholene oxides was prepared from the corresponding 3-phospholene oxides by double bond rearrangement. The 2-phospholene oxides could be obtained by heating the 3-phospholene oxides in methanesulfonic acid, or via the formation of cyclic chlorophosphonium salts. Whereas mixtures of the 2- and 3-phospholene oxides formed, when the isomerization of 3-phospholene oxides was attempted under thermal conditions, or in the presence of a base. The mechanisms of the various double bond migration pathways were elucidated by quantum chemical calculations.