134780-16-8Relevant articles and documents
Highly Active Cooperative Lewis Acid—Ammonium Salt Catalyst for the Enantioselective Hydroboration of Ketones
Titze, Marvin,Heitk?mper, Juliane,Junge, Thorsten,K?stner, Johannes,Peters, René
supporting information, p. 5544 - 5553 (2021/02/05)
Enantiopure secondary alcohols are fundamental high-value synthetic building blocks. One of the most attractive ways to get access to this compound class is the catalytic hydroboration. We describe a new concept for this reaction type that allowed for exceptional catalytic turnover numbers (up to 15 400), which were increased by around 1.5–3 orders of magnitude compared to the most active catalysts previously reported. In our concept an aprotic ammonium halide moiety cooperates with an oxophilic Lewis acid within the same catalyst molecule. Control experiments reveal that both catalytic centers are essential for the observed activity. Kinetic, spectroscopic and computational studies show that the hydride transfer is rate limiting and proceeds via a concerted mechanism, in which hydride at Boron is continuously displaced by iodide, reminiscent to an SN2 reaction. The catalyst, which is accessible in high yields in few steps, was found to be stable during catalysis, readily recyclable and could be reused 10 times still efficiently working.
Asymmetric hydrogenation of ketones with H2 and ruthenium catalysts containing chiral tetradentate S2N2 ligands
Patchett, Ruth,Magpantay, Iris,Saudan, Lionel,Schotes, Christoph,Mezzetti, Antonio,Santoro, Francesco
supporting information, p. 10352 - 10355 (2013/10/21)
Getting more for less: In the presence of H2 and a base, air- and moisture-tolerant RuII complexes catalyze the hydrogenation of ketones and aldehydes with excellent activity and chemoselectivity, and with enantioselectivity of up to 95 % under mild conditions. The ratio of substrate to catalyst can be lowered to 106:1. The reactions tolerate scale-up and can be carried out with almost no solvent. A base-free method is available for base-sensitive substrates. Copyright
Enantioselective microbial oxidation of allyl alcohols
Matsumoto, Kazutsugu,Kawabata, Yoichi,Okada, Satoshi,Takahashi, Jun,Hashimoto, Key,Nagai, Yuto,Tatsuta, Junichi,Hatanaka, Minoru
, p. 1428 - 1429 (2008/03/18)
A new route to the optically active allyl alcohols by microbial oxidation is disclosed. Yamadazyma farinosa IFO 10896, a yeast, efficiently catalyzes the enantioselective oxidation of allyl alcohols to afford the corresponding optically active alcohols as the remaining substrates. This reaction is applicable to both cyclic and acyclic compounds. Copyright