Complexes of Rare- and Alkaline-Earth Elements in Catalytic Intermolecular Hydrophosphination of Multiple C—C Bonds

Abstract

In accordance with United Nations General Assembly resolution, the year 2019 was proclaimed the International Year of the Periodic Table of Chemical Elements. Rare-earth elements were discovered during the time of the Periodic System development. In the past few decades, their compounds have attracted great interest due to their unique reactivity. This review covers recent achievements in the field of intermolecular hydrophosphination of alkenes, dienes and alkynes, which is catalyzed by rare earth and alkaline-earth metal complexes. Catalytic hydrophosphination reaction is the addition of an P—H bond to С—С multiple bonds, and offers an efficient and elegant synthetic approach to production of the organophosphorus compounds widely used in industrial synthesis, pharmaceuticals, agrochemistry, and other areas. The high values of the ionic radii of rare earth and alkaline-earth metals in combination with the Lewis acidity provide their compounds with a pronounced tendency to complex formation and, accordingly, high coordination numbers. Due to high reactivity of M—E (E = C, H, N, P) bonds, ease of Ln—P ı-bond metathesis and multiple C—C bond insertions, these compounds offer new prospects for the catalysis of the alkenes and alkynes hydrophosphination. Therefore, complexes of non-toxic and relatively abundant in nature rare earth and alkaline earth metals can be a cheaper and more effective alternative to compounds of late transition metals in the catalysis of the C—P bond formation.