181229-59-4Relevant academic research and scientific papers
Efficient lipase-catalyzed enantioselective acylation under reduced pressure conditions in an ionic liquid solvent system
Itoh, Toshiyuki,Akasaki, Eri,Nishimura, Yoshihito
, p. 154 - 155 (2002)
Lipase-catalyzed transesterification was demonstrated using methyl esters as acyl donors under reduced pressure in an ionic liquid ([bmim]PF6) solvent system. The transesterification of 5-phenyl-1-penten-3-ol took place smoothly under reduced p
Enantioselective vinylation of aldehydes with the vinyl Grignard reagent catalyzed by magnesium complex of chiral BINOLs
Wang, Pei,Ma, Guo-Rong,Yu, Sheng-Li,Da, Chao-Shan
supporting information, p. 79 - 86 (2018/12/13)
Enantioselective vinylation of aldehydes via direct catalytic asymmetric Grignard reaction of aldehdyes and the vinyl Grinard reagent is a long-standing challenge. This work demonstrated that the magnesium (S)-3,3′-dimethyl BINOLate enantioselectively catalyze the direct vinylation of aldehydes with the deactivated vinylmagnesium bromide by bis(2-[N,N′-dimethylamino]ethyl) ether (BDMAEE) in the addition of n-butylmagnesium chloride. The highest ee of 63% was achieved up to date.
Enhanced activity and modified substrate-favoritism of Burkholderia cepacia lipase by the treatment with a pyridinium alkyl-PEG sulfate ionic liquid
Kadotani, Shiho,Nokami, Toshiki,Itoh, Toshiyuki
, p. 441 - 447 (2019/01/04)
Three types of pyridinium salts, i.e., 1-ethylpyridin-1-ium cetyl-PEG10 sulfate (PYET), 1-butylpyridin-1-ium cetyl-PEG10 sulfate (PYBU), and 1-(3-methoxypropyl)pyridin-1-ium cetyl-PEG10 sulfate (PYMP), have been prepared and evaluated for their activation property of Burkholderia cepacia lipase by comparison to the control IL-coated enzymes, 1-butyl-2,3-dimethylimidazolium cetyl-PEG10 sulfate-coated lipase PS (IL1-PS). Among the tested pyridinium salt-coated lipases, the PYET-coated lipase PS (PYET-PS) exhibited the best results; the transesterification of 1-(pyridin-2-yl)ethanol, 1-(pyridin-3-yl)ethanol, 1-(pyridin-4-yl)ethanol, or 4-phenylbut-3-en-2-ol proceeded faster than those of the IL1-PS-catalyzed reaction while maintaining an excellent enantioselectivity (E > 200). This improved efficiency was found to be dependent on the increased Kcat value.
Rhodium-Catalyzed Regio- and Enantioselective Addition of N-Hydroxyphthalimide to Allenes: A Strategy to Synthesize Chiral Allylic Alcohols
Liu, Zi,Breit, Bernhard
supporting information, p. 300 - 303 (2018/01/17)
We achieved the first Rh-catalyzed regio- and enantioselective additions of N-hydroxyphthalimide to allenes. This transformation is accomplished via mild reaction conditions, leveraging on Josiphos SL-J003-2 as a chiral ligand to furnish branched O-allyl compounds in good yields with moderate to excellent enantioselectivities. The substrate scope is broad, and various functional groups are tolerated. The utility of this methodology is elaborated by transformation to allylic alcohols with different functional groups as well as to chiral O-allyl hydroxylamines.
Enantioselective transformation of allyl carbonates into branched allyl carbamates by using amines and recycling CO2 under iridium catalysis
Zheng, Sheng-Cai,Zhang, Min,Zhao, Xiao-Ming
supporting information, p. 7216 - 7221 (2014/06/23)
Enantioselective transformation of allyl carbonates into branched allyl carbamates by using amines and recycling CO2 in the presence of an Ir complex and K3PO4 was accomplished. This provided branched allyl carbamates in fair to excellent yields with up to 98:2 regioselectivity and 93% ee. The role of CO2 in this transformation is discussed as well.
Concise stereoselective total synthesis of (4 R, 6 R)-lactone moiety analog of mevinoline and compactin
Rao, D. Chandra,Reddy, D. Kumar,Chinnababu,Shekhar,Venkateswarlu
supporting information, p. 2980 - 2984 (2013/09/12)
A simple and highly efficient synthetic route has been developed for analogue of HMGCo A reductase inhibitor (1). The strategy utilizes S-Corey-Bakshi-Shibata (CBS) reduction, FeCl3-catalyzed C-H insertion of ethyl diazoacetate.
Kinetic resolution of allylic alcohols via stereoselective acylation catalyzed by lipase PS-30
Chen, Peiran,Xiang, Peng
experimental part, p. 5758 - 5760 (2011/12/03)
By using lipase PS-30 as catalyst, the kinetic resolution of a series of racemic allylic alcohols has been achieved via stereoselective acylation. The value of kinetic enantiomeric ratio (E) reached up to 968. Substituent effect is briefly discussed.
Enantio- and regioselective iridium-catalyzed allylic hydroxylation
Gaertner, Martin,Mader, Steffen,Seehafer, Kai,Helmchen, Guenter
supporting information; experimental part, p. 2072 - 2075 (2011/04/16)
The first enantioselective allylic hydroxylation to prepare branched allylic alcohols directly is described. Bicarbonate was used as nucleophile in conjunction with new single component Ir-catalysts, which are stable to air and water. Excellent regio- and
The use of COP-OAc in the catalyst-controlled syntheses of 1,3-polyols
Kirsch, Stefan F.,Klahn, Philipp,Menz, Helge
supporting information; experimental part, p. 3592 - 3603 (2011/12/21)
An iterative strategy to the 1,3-polyol motif is described. The use of the catalytic asymmetric Overman esterification for the construction of all stereogenic centers is broadly examined as are the sequences to extend the developing polyol chain. The iterative strategies are applied to the total syntheses of rugulactone and polyrhacitides A and B. 1 Introduction 2 Results and Discussion 2.1 Chain Elongation via RCM (Cycle A) 2.2 Total Synthesis of Rugulactone 2.3 Chain Elongation via Ando Olefination (Cycle B) and Total Syntheses of Polyrhacitides A and B 2.4 Useful Variants 3 Conclusions. Georg Thieme Verlag Stuttgart. New York.
Ruthenium-catalyzed regio- and enantioselective allylic substitution with water: Direct synthesis of chiral allylic alcohols
Kanbayashi, Naoya,Onitsuka, Kiyotaka
supporting information; experimental part, p. 5197 - 5199 (2011/06/26)
Less is more: A new route to access chiral allylic alcohols through the regio- and enantioselective substitution of monosubstituted allylic chlorides with water has been developed. The reaction is catalyzed effectively by planar-chiral cyclopentadienyl ruthenium complexes (see scheme). Copyright
