1232403-88-1Relevant articles and documents
Enantioselective synthesis of amines by combining photoredox and enzymatic catalysis in a cyclic reaction network
Guo, Xingwei,Okamoto, Yasunori,Schreier, Mirjam R.,Ward, Thomas R.,Wenger, Oliver S.
, p. 5052 - 5056 (2018/06/12)
Visible light-driven reduction of imines to enantioenriched amines in aqueous solution is demonstrated for the first time. Excitation of a new water-soluble variant of the widely used [Ir(ppy)3] (ppy = 2-phenylpyridine) photosensitizer in the p
Expanding the chemical diversity in artificial imine reductases based on the biotin-streptavidin technology
Quinto, Tommaso,Schwizer, Fabian,Zimbron, Jeremy M.,Morina, Albert,Koehler, Valentin,Ward, Thomas R.
, p. 1010 - 1014 (2014/05/06)
We report on the optimization of an artificial imine reductase based on the biotin-streptavidin technology. With the aim of rapidly generating chemical diversity, a novel strategy for the formation and evaluation of biotinylated complexes is disclosed. Tethering the biotin-anchor to the Cp* moiety leaves three free coordination sites on a d6 metal for the introduction of chemical diversity by coordination of a variety of ligands. To test the concept, 34 bidentate ligands were screened and a selection of the 6 best was tested in the presence of 21 streptavidin (Sav) isoforms for the asymmetric imine reduction by the resulting three legged piano stool complexes. Enantiopure α-amino amides were identified as promising bidentate ligands: up to 63 % ee and 190 turnovers were obtained in the formation of 1-phenyl-1,2,3,4-tetrahydroisoquinoline with [IrCp*biotin(L-ThrNH2)Cl]?SavWT as a catalyst. Biotinspired! A new strategy for the generation of chemical diversity in artificial transfer hydrogenases (ATHases) based on the biotin-streptavidin technology is disclosed. By combining a biotinylated MCp* fragment with 34 commercially available ligands in the presence of wild-type streptavidin, promising candidates for the asymmetric reduction of imines are identified. Selected ligands are screened against 21 streptavidin isoforms and the performance of the resulting constructs is evaluated.
Enantioconvergent cross-couplings of racemic alkylmetal reagents with unactivated secondary alkyl electrophiles: Catalytic asymmetric Negishi α-alkylations of N-Boc-pyrrolidine
Cordier, Christopher J.,Lundgren, Rylan J.,Fu, Gregory C.
, p. 10946 - 10949 (2013/08/23)
Although enantioconvergent alkyl-alkyl couplings of racemic electrophiles have been developed, there have been no reports of the corresponding reactions of racemic nucleophiles. Herein we describe Negishi cross-couplings of racemic α-zincated N-Boc-pyrrolidine with unactivated secondary halides, thus providing a one-pot, catalytic asymmetric method for the synthesis of a range of 2-alkylpyrrolidines (an important family of target molecules) from N-Boc-pyrrolidine, a commercially available precursor. Preliminary mechanistic studies indicated that two of the most straightforward mechanisms for enantioconvergence (dynamic kinetic resolution of the organometallic coupling partner and a simple β-hydride elimination/β-migratory insertion pathway) are unlikely to be operative.
