62673-29-4Relevant articles and documents
Synthesis of the tantalum hydride complex (R,R)-[Ta(O2C 20H10 {SiMe3}2-3,3′) 2(H)] and reactivity with aldehydes, ketones, acetylenes, and related substrates: A reagent for the asymmetric hydrogenation of prochiral carbonyl species
Weinert, Charles S.,Fanwick, Phillip E.,Rothwell, Ian P.
, p. 5759 - 5766 (2008/10/09)
The tantalum phenyl complex (R,R)-[Ta(O2C20H 10{SiMe3}2-3,3′)2(Ph)], (R,R)-1, has been prepared from [H2NEt2][Ta(O 2C20H10{SiMe3}2-3, 3′}2Cl2] and has been employed for the synthesis of the hydride species (R,R)-[Ta(O2C20H 10{SiMe3}2-3,3′)2(H)], (R,R)-2, by reaction with diisobutylaluminum hydride (DIBAL-H). The reaction proceeds cleanly and in high yield. Compound (R,R)-2 undergoes clean reactions with acetophenone and benzaldehyde-d to give alkoxide complexes that are chiral at the α-carbon. The progress of these reactions was monitored by 13C NMR spectroscopy. An X-ray crystal structure of one of the products (R,R,R)/(R,R,S)-[Ta(O2C20H10{SiMe 3}2-3,3′)2(OCH{CH3}{Ph})(O= C{CH3}{Ph})] was obtained, and the catalytic conversion of benzaldehyde-d to benzyl alcohol-d was carried out using (R,R)-2. The hydride complex also reacts with acetylenes to give vinyl metal complexes, with 2,6-dimethylphenyl isocyanide to give an iminoformyl complex, and with allene to yield a labile η3-π-allyl species.
