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

Péter Bagi; Réka Herbay; Nikolett Péczka; Zoltán Mucsi; István Timári; And György Keglevich

doi:10.3762/bjoc.16.75

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

Beilstein J Org Chem. 2020 Apr 22:16:818-832. doi: 10.3762/bjoc.16.75. eCollection 2020.

Authors

Péter Bagi¹, Réka Herbay¹, Nikolett Péczka¹, Zoltán Mucsi², István Timári³, And György Keglevich¹

Affiliations

¹ Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Műegyetem rkp. 3., H-1111 Budapest, Hungary.
² Femtonics Ltd., H-1094 Budapest, Hungary.
³ Department of Inorganic and Analytical Chemistry, University of Debrecen, H-4032 Debrecen, Hungary.

Abstract

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.

Keywords: 2-phospholene oxides; 3-phospholene oxides; chlorophosphonium salts; isomerization; quantum chemistry.

Grants and funding

This work was supported by the National Research, Development and Innovation Office - NKFIH (Grant No. OTKA PD 116096 and NVKP_16-1-2016-0043). The research of I.T. was supported by the EU and co-financed by the European Regional Development Fund under the GINOP-2.3.2-15-2016-00008 project.