120443-82-5Relevant articles and documents
Design of a well-defined, silica-supported chiral Zn scaffold for enantioselective catalysis
Ternel, Jeremy,Delevoye, Laurent,Agbossou-Niedercorn, Francine,Roisnel, Thierry,Gauvin, Regis M.,Thomas, Christophe M.
, p. 3802 - 3804 (2010)
New compound Zn[(S,S)-iPr-pybox](Et)2 (1) was fully characterized, including by X-ray diffraction structural studies. Its grafting onto partially dehydroxylated silica affords material 2, which bears well-defined chiral (SiO)Zn[(S,S)-iPr-pybox]
Chiral vanadyl Schiff base complex anchored on silicas as solid enantioselective catalysts for formation of cyanohydrins: Optimization of the asymmetric induction by support modification
Baleizao, Carlos,Gigante, Barbara,Garcia, Hermenegildo,Corma, Avelino
, p. 199 - 207 (2003)
A series of vanadyl Schiff base complexes having a terminal carbon-carbon double bond pending alkyl chains of various lengths attached to the para position of the salen ligand were prepared and anchored on three large surface area silicas, i.e., amorphous
Lithium salts of chiral metallocomplex anions as catalysts for asymmetric trimethylsilylcyanation of aldehydes
Maleev,Skrupskaya,Savel'eva,Mkrtchyan,Saghiyan
, p. 598 - 604 (2010)
A series of the anionic CoIII complexes based on optically active amino acids containing the lithium cation in the external sphere of the complex was synthesized. The synthesized com- pounds were used as catalysts in the asymmetric addition of
The asymmetric addition of trimethylsilylcyanide to aldehydes catalysed by anionic chiral nucleophiles. Part 2
Holmes,Kagan
, p. 7457 - 7460 (2000)
Studies have been carried out on the addition of trimethylsilylcyanide to aldehydes using highly active chiral lithium phenolate catalysts. The screening of a number of chiral phenolates has resulted in a system which gives the TMS ethers of cyanohydrins
Catalytic, asymmetric cyanohydrin synthesis in propylene carbonate
North, Michael,Omedes-Pujol, Marta
, p. 4452 - 4454 (2009)
Propylene carbonate can be used as a green solvent for asymmetric cyanohydrin synthesis catalyzed by VO(salen)NCS. A range of 10 aromatic and aliphatic aldehydes gave high enantioselectivities (up to 93%) and conversions (up to 100%) in reactions carried
Asymmetric trimethylsilylcyanation of benzaldehyde catalyzed by (salen)Ti(IV) complexes derived from (R)- and/or (S)-4-hydroxy-5-formyl[2.2]paracyclophane and diamines
Belokon', Yuri,Moscalenko, Margarita,Ikonnikov, Nicolai,Yashkina, Lidia,Antonov, Dmitri,Vorontsov, Evgeni,Rozenberg, Valeria
, p. 3245 - 3250 (1997)
Benzaldehyde has been asymmetrically trimethylsilylcyanated, using chiral (salen)Ti(IV) catalysts 1a and 1b, 2a and 2b, 3a and 3b prepared in situ from titanium tetraisopropoxide and the Schiff's bases derived from (R)- or (S)-4-hydroxy-5-formyl[2.2]parac
Chiral ion pairs in catalysis: lithium salts of chiral metallocomplex anions as catalysts for asymmetric C-C bond formation
Belokon', Yuri N.,Maleev, Victor I.,Kataev, Dmitri A.,Saveleva, Tatiana F.,Skrupskaya, Tatiana V.,Nelyubina, Yulia V.,North, Michael
, p. 1746 - 1752 (2009)
A series of Co(III) anionic complexes of Schiff bases obtained from substituted salicylaldehydes and optically active amino acids has been synthesized. The ion pairing of these anions to a lithium cation can be used to induce asymmetry into lithium-cataly
Asymmetric catalysis in a micro reactor - Ce, Yb and Lu catalysed enantioselective addition of trimethylsilyl cyanide to benzaldehyde
J?nsson, Christina,Lundgren, Stina,Haswell, Stephen J.,Moberg, Christina
, p. 10515 - 10520 (2004)
A T-shaped micro reactor was used for the optimisation of reaction conditions for the enantioselective silylcyanation of benzaldehyde catalysed by lanthanide-pybox complexes. Compared to a conventional batch procedure, higher conversion was observed within shorter reaction time. The micro reactor process involving Lu(III) afforded essentially the same enantioselectivity as the batch process (73 vs 76% ee), whereas the enantioselectivity was lower in the micro reactor for catalysts containing Yb(III) (53 compared to 72%). Ce(III) provided very low selectivity in both types of processes (1 and 11% ee, respectively). A study of the effect of additives showed that the enantioselectivity in the Yb catalysed reaction performed in the micro reactor could be increased to 66%, whereas only a minor improvement, to 78% ee, was observed in the reaction with Lu. Graphical Abstract.
Encapsulation of Homogeneous Catalysts in Mesoporous Materials Using Diffusion-Limited Atomic Layer Deposition
Zhang, Shufang,Zhang, Bin,Liang, Haojie,Liu, Yequn,Qiao, Yan,Qin, Yong
, p. 1091 - 1095 (2018)
The heterogenization of homogeneous metal complex catalysts has attracted great attention. The encapsulation of metal complexes into nanochannels of mesoporous materials is achieved by coating metal oxides at/near the pore entrance by diffusion-limited atomic layer deposition (ALD) to produce a hollow plug. The pore size of the hollow plug is precisely controlled on the sub-nanometer scale by the number of ALD cycles to fit various metal complexes with different molecular sizes. Typically, Co or Ti complexes are successfully encapsulated into the nanochannels of SBA-15, SBA-16, and MCM-41. The encapsulated Co and Ti catalysts show excellent catalytic activity and reusability in the hydrolytic kinetic resolution of epoxides and asymmetric cyanosilylation of carbonyl compounds, respectively. This ALD-assisted encapsulation method can be extended to the encapsulation of other homogeneous catalysts into different mesoporous materials for various heterogeneous reactions.
Asymmetric synthesis of cyanohydrins catalysed by a potassium Δ-bis[N-salicylidene-(R)-tryptophanato]cobaltate complex
Belokon, Yuri N.,Bulychev, Alexander G.,Maleev, Victor I.,North, Michael,Malfanov, Ilja L.,Ikonnikov, Nikolai S.
, p. 249 - 250 (2004)
A chiral cobalt(III) complex of a Schiff base derived from (R)-tryptophan and salicylaldehyde catalysed asymmetric trimethylsilylcyanation of benzaldehyde at ambient temperature and a 20:1 substrate/catalyst ratio with the formation of enantiomerically en
