194545-44-3Relevant articles and documents
Semi-continuous flow biocatalysis with affinity co-immobilized ketoreductase and glucose dehydrogenase
Petrovi?ová, Tatiana,Pl?, Michal,Rebro?, Martin
, (2020)
The co-immobilization of ketoreductase (KRED) and glucose dehydrogenase (GDH) on highly cross-linked agarose (sepharose) was studied. Immobilization of these two enzymes was performed via affinity interaction between His-tagged enzymes (six histidine resi
An industrial perspective fermentative bioreduction of aromatic ketones by Penicillium rubens VIT SS1 and Penicillium citrinum VIT SS2
Jothi, Saravanan,Vuppu, Suneetha
, (2021/08/18)
Microbial mediated, especially the fungi mediated asymmetric reduction of the ketone is one of the most promising tools for the synthesis of chiral alcohols. Many fungal cultures were isolated from soil and screened for the stereo selective bioreduction of acetophenone. The potential isolates are characterised using molecular techniques and found to be Penicillium rubens VIT SS1 (Genbank ID: MK063869) and Penicillium citrinum VIT SS2 (Genbank ID: MW960208). Both the isolates were tested for the bioreduction of few aromatic ketones such as 4-fluoro acetophenone, 3-hydroxy acetophenone, and oxcarbazepine, which are the key chiral intermediates of various pharmaceutical drugs. The P. rubens VIT SS1 produced (S)-alcohol obeying Prelog’s rule, and P. citrinum was anti-Prelog configuration in nature. Preparatory scale reactions were conducted using the optimised bioreduction process, and the keto loading was significantly increased by 12-fold (from 0.5 to 6 g/L) with >99% conversion and >98% enantiomeric excess. The study discloses the vast prospective approach of exploring filamentous fungi for sustainable synthesis of chiral alcohols in an environment-friendly, novel, and cost competent way.
Chiral Iron(II)-Catalysts within Valinol-Grafted Metal-Organic Frameworks for Enantioselective Reduction of Ketones
Akhtar, Naved,Antil, Neha,Begum, Wahida,Chauhan, Manav,Kumar, Ajay,Manna, Kuntal,Newar, Rajashree
, p. 10450 - 10459 (2021/08/31)
The development of highly efficient and enantioselective heterogeneous catalysts based on earth-abundant elements and inexpensive chiral ligands is essential for environment-friendly and economical production of optically active compounds. We report a strategy of synthesizing chiral amino alcohol-functionalized metal-organic frameworks (MOFs) to afford highly enantioselective single-site base-metal catalysts for asymmetric organic transformations. The chiral MOFs (vol-UiO) were prepared by grafting of chiral amino alcohol such as l-valinol within the pores of aldehyde-functionalized UiO-MOFs via formation of imine linkages. The metalation of vol-UiO with FeCl2 in THF gives amino alcohol coordinated octahedral FeII species of vol-FeCl(THF)3 within the MOFs as determined by X-ray absorption spectroscopy. Upon activation with LiCH2SiMe3, vol-UiO-Fe catalyzed hydrosilylation and hydroboration of a range of aliphatic and aromatic carbonyls to afford the corresponding chiral alcohols with enantiomeric excesses up to 99%. Vol-UiO-Fe catalysts have high turnover numbers of up to 15 ?000 and could be reused at least 10 times without any loss of activity and enantioselectivity. The spectroscopic, kinetic, and computational studies suggest iron-hydride as the catalytic species, which undergoes enantioselective 1,2-insertion of carbonyl to give an iron-alkoxide intermediate. The subsequent σ-bond metathesis between Fe-O bond and Si-H bond of silane produces chiral silyl ether. This work highlights the importance of MOFs as the tunable molecular material for designing chiral solid catalysts based on inexpensive natural feedstocks such as chiral amino acids and base-metals for asymmetric organic transformations.
