Metallacyclic yttrium alkyl and hydrido complexes: synthesis, structures and catalytic activity in intermolecular olefin hydrophosphination and hydroaminationElectronic supplementary information (ESI) available. CCDC 1024799-1024802. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5dt00129c

• Main Authors: Kissel, Alexander A, Mahrova, Tatyana V, Lyubov, Dmitry M, Cherkasov, Anton V, Fukin, Georgy K, Trifonov, Alexander A, Del Rosal, Iker, Maron, Laurent
• Format: Article
• Language: English
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c5dt00129c

Metallacyclic neutral and ionic yttrium alkyl complexes coordinated by a dianionic ene-diamido ligand ([2,6-iPr 2 C 6 H 3 NC(Me)&z.dbd;C(Me)NC 6 H 3 iPr 2 -2,6] = L 1 ) [L 1 ]Y(CH 2 SiMe 3 )(THF) 2 ( 2 ), {[L 1 ]Y(CH 2 SiMe 3 ) 2 } − {Li(THF) 4 } + ( 3 ), [L 1 ]Y(OEt 2 )(μ-Me) 2 Li(TMEDA) ( 4 ) were synthesized using a salt-metathesis approach starting from the related chloro complex [L 1 ]Y(THF) 2 (μ-Cl) 2 Li(THF) 2 ( 1 ) in 70, 85 and 72% yields respectively. The reactions of 2 with H 2 or PhSiH 3 afford the dimeric hydride {[L 1 ]Y(THF)(μ-H)} 2 (μ-THF) ( 5 ) containing two μ-bridging hydrido and one μ-bridging THF ligands (91 and 85% yields). The X-ray studies of complexes 2 , 3 and 5 revealed η 2 -coordination of the C&z.dbd;C fragment of an ene-diamido ligand to a Y cation. DFT calculations were carried out to give an insight into the metal-ligand bonding and especially the interaction between the metal and the ene-diamido ligand. The observed bonding of the ene-diamido fragment is found to reflect the acidity of the metal center in the complex that is partially overcome by a better donation from the double bond (better overlap with an empty d orbital at the yttrium center). The treatment of complex 4 with DME resulted in the C-O bond cleavage of DME and afforded a three nuclear methoxide oxide complex [{[L 1 ]Y} 3 (μ 2 -OMe) 3 (μ 3 -O)] 2− [Li(DME) 3 ] + 2 ( 6 ). Complexes 2 , 3 , 5 and 7 proved to be efficient precatalysts for the intermolecular hydrophosphination of styrene, 4-vinylpyridine, and 1-nonene with PhPH 2 and Ph 2 PH as well as hydroamination of styrene and pyrrolidine. Yttrium complexes - efficient precatalysts for intermolecular olefin hydrophosphination and hydroamination.