Calcium-Mediated Intramolecular Hydroamination Catalysis

Abstract

The calcium-catalyzed intramolecular hydroamination of alkenes and alkynes is reported. The beta-diketiminato complex [{HC(C(Me)2N-2,6-iPr2C6H3)2}-Ca{N(SiMe3)2}(THF)] affects catalytic cyclization of a range of aminoalkenes and aminoalkynes with activities that are broadly commensurate to those of established rare earth catalysts.

Iridium-Catalyzed, Intermolecular Hydroetherification of Unactivated Aliphatic Alkenes with Phenols

“…Hill and coworkers examined the intramolecular hydroamination of aminoalkenes catalyzed by calcium amido and magnesium amido complexes ligated by b diketiminates (Scheme 14). [66,67] Kinetic analysis of the reaction catalyzed by the magnesium system revealed a first-order dependence on catalyst concentration and an inverse first-order dependence on the concentration of aminoalkene. Although preliminary, these data are consistent with a mechanism involving turnover-limiting insertion of alkene into the M À N bond, which occurs after dissociation of one substrate from the metal center.…”

Heterofunctionalization catalysis with organometallic complexes of calcium, strontium and barium

“…A number of homoleptic complexes of the form MX 1 2 , however, have also been reported as pre-catalysts for heterofunctionalization of unsaturated substrates. (Crimmin et al 2005(Crimmin et al , 2009). Reactions were shown to proceed in high yield under mild conditions (25-80…”

Lithium Dihydropyridine Dehydrogenation Catalysis: A Group 1 Approach to the Cyclization of Diamine Boranes

“…Emerging from years of curiosity‐driven research that uncovered novel structures and bonding, main‐group (pre)catalysts have recently found application in a range of important catalytic processes, including hydroamination,2 hydroboration and hydrosilylation,3 hydrogenation,4 and dehydrogenative element–element bond formation 5. The last named is particularly relevant since the catalytic control of dehydrocoupling processes (e.g., formation of B−N bonds) has relevance to hydrogen storage6 as well as utility in the synthesis of polymers and preceramic materials 7.…”