Recent advances in organo- lanthanides and actinides mediated hydroaminations

Abstract

Hydroamination, an atom-economic one-step reaction that refers to the addition of an NH unit into CC/CX multiple bonds, provides an ideally efficient methodology to construct C–N bonds. Due to the presence of the f-orbitals, organo- lanthanides and actinides mediated hydroamination generally reveal distinct differences and in some cases complementary catalytic behaviors when compared to early/late-transition metals and main group metal complexes. The earliest organo-f-metal catalyzed hydroamination can be dated back to 1989, and since then numerous organo-f-metal complexes have been designed and systematically explored. According to the types of the ligands, the authors roughly divided the past thirty-three years of development into three stages. In the 1st stage (1989–1998), only metallocene-types, lanthanocenes and actinocenes, served as the catalysts. In the 2nd stage (1999–2008), post-metallocene complexes appeared and started to grow thereafter, and in a ten-year development, the number of reports on both metallocene and post-metallocene catalysts is similar. These two stages have been comprehensively reviewed previously. Since 2009 (3rd stage), more and more post-metallocene catalysts were exploited and soon became the predominant type of catalysts. Therefore, this review covers the reports in the 3rd stage, which mainly are post-metallocene complexes that bear mono-, bi-, tri-, and tetra-dentate ligands. Different from previous reviews that only focus on challenging alkene or alkyne substrates (CC multiple bonds), this review also includes CX multiple bonds containing substrates to give a better catalytic hydroamination map of the organo-f-metal complexes. In the end, we also give our personal “Quo Vadis” opinions on some challenging questions and where this field should continue to develop.