42558-50-9Relevant articles and documents
General chemoenzymatic route to two-stereocenter triketides employing assembly line ketoreductases
Zhang, Zhicheng,Cepeda, Alexis J.,Robles, Mireya L.,Hirsch, Melissa,Kumru, Kaan,Zhou, Jina A.,Keatinge-Clay, Adrian T.
supporting information, p. 157 - 160 (2019/12/25)
Modular polyketide synthases (PKSs) are enzymatic assembly lines that fuse carbon fragments into complex chiral products. Here, their synthetic logic is employed to chemoenzymatically generate two-stereocenter triketides. Each of the four stereoisomers was constructed in a stereocontrolled manner using C-acylation and two PKS ketoreductases possessing opposite stereoselectivities.
Copper-Catalyzed Asymmetric Conjugate Additions of Bis(pinacolato)diboron and Dimethylzinc to Acyl- N-methylimidazole Michael Acceptors: A Highly Stereoselective Unified Strategy for 1,3,5,... n (OH, Me) Motif Synthesis
Lauberteaux, Jimmy,Crévisy, Christophe,Baslé, Olivier,De Figueiredo, Renata Marcia,Mauduit, Marc,Campagne, Jean-Marc
supporting information, p. 1872 - 1876 (2019/03/11)
A unified strategy for the construction of prevalent 1,3,5,...n (OH, Me) motifs based on consecutive copper-catalyzed asymmetric conjugate borylation (ACB) and methylation (ACA) reactions involving α,β-unsaturated 2-acyl-N-methylimidazoles is described. Good yields and high diastereoselectivities have been obtained in ACA and ACB reactions for both matched and mismatched pairs as illustrated in the synthesis of syn/anti and anti/anti (Me, OTBS, Me) and (OH, OTBS, Me) motifs.
2-(1S)-Camphanoyloxy-2′-phosphanylbiphenyl Ligands – Synthesis, Structure, and Preliminary Tests in Transition-Metal Catalysis
Wawrzyniak, Piotr,Kindermann, Markus K.,Thede, Gabriele,Thede, Richard,Jones, Peter G.,Enthaler, Stephan,Junge, Kathrin,Beller, Matthias,Heinicke, Joachim W.
, p. 2762 - 2773 (2017/06/06)
Diastereoisomer separation of the (1S)-camphanic acid 2-isopropylphenylphosphanyl-phenyl ester 1 exemplifies the potential of (1S)-camphanoyl chloride for enantiomer separation of hydroxyl-functional asymmetric phosphanes. Esterification of lithium 2′-phosphanylbiphenyl-2-olates, generated from the respective 2-OH or 2-OSiMe3 precursors 2aOH and 2b–fSi, furnished the 2-(1S)-camphanoyloxy-biphenylphosphanes 3a–c as 1:1 mixtures of diastereomers with low barriers for interconversion by rotation around the C–C axis (ΔG# = 70–73 kJ mol–1 for 3a and 3c by 31P VT NMR spectroscopy). The P-asymmetric compounds 3d–f form 1:1 mixtures of stereoisomers. There is a tendency to cocrystallization of two preferred diastereoisomers, as shown by the crystal structure analyses of 3dD and 3fD, and in solution, there is a tendency toward partial isomerization to the sterically less-favored atropisomers. The [RhCl(cod)(3dD)] complex 4dD, however, seems stable in solution. Excess 2dLi reacted with (1S)-camphanoyl chloride preferentially to form the (SP,Rax,1S) isomer, which was separated by crystallization as enantiopure 3dE, characterized by single-crystal XRD. Preliminary screening tests of this ligand in Rh-catalyzed asymmetric hydrogenations of N-(1-phenylvinyl)acetamide allowed high conversion and up to 59 % ee. Hydrosilylation of acetophenone proceeded with 78 % conversion and 48 % ee; Suzuki–Miyaura couplings of 1-bromo-2-naphthol with PhB(OH)2, in the presence of 3b/[Pd(OAc)2], gave yields up to 98 %.
