156927-76-3Relevant articles and documents
Time-dependent enantiodivergent synthesis via sequential kinetic resolution
Tu, Hang-Fei,Yang, Pusu,Lin, Zi-Hua,Zheng, Chao,You, Shu-Li
, p. 838 - 844 (2020)
The preparation of both enantiomers of chiral molecules is among the most fundamental tasks in organic synthesis, medicinal chemistry and materials science. Achieving this goal typically requires reversing the absolute configuration of the chiral component employed in the reaction system that is being used. The task becomes challenging when the natural source of the chiral component is not available in both configurations. Herein, we report a time-dependent enantiodivergent synthesis, in which an Ir-catalysed allylic substitution reaction uses one catalyst sequentially to promote two kinetic resolution reactions, enabling the synthesis of both enantiomers of the product using the same enantiomer of a chiral catalyst. The appropriate permutation of individual reaction rates is essential for the isolation of the chiral products in opposite configurations with high enantiopurity when quenched at different reaction times. This work provides an alternative solution for the preparation of both enantiomers of chiral molecules. [Figure not available: see fulltext.].
Regio- and Enantioselective Allylation of Phenols via Decarboxylative Allylic Etherification of Allyl Aryl Carbonates Catalyzed by (Cyclopentadienyl)ruthenium(II) Complexes and Pyridine-Hydrazone Ligands
Egger, Léo,Tortoreto, Cecilia,Achard, Thierry,Monge, David,Ros, Abel,Fernández, Rosario,Lassaletta, José M.,Lacour, Jér?me
, p. 3325 - 3331 (2015/11/03)
(Cyclopentadienyl)tris(acetonitrile)ruthenium hexafluorophosphate [CpRu(CH3CN)3][PF6] in combination with pyridine-hydrazone ligands efficiently catalyzes the asymmetric decarboxylative allylic rearrangement of allyl aryl carbonates. Formation of C-O bonds with high regio- and enantioselectivity ratios (up to 95:5 and 98% ee) is obtained. Good stereocontrol of the pseudotetrahedral geometry of the CpRu moiety is achieved by the hydrazone ligand and its "electron-poor" nature is evidenced through the epimerization of the hexacoordinated TRISPHAT-N anion.
(Cyclopentadienyl)ruthenium-catalyzed regio- and enantioselective decarboxylative allylic etherification of allyl aryl and alkyl carbonates
Austeri, Martina,Linder, David,Lacour, Jerome
scheme or table, p. 3339 - 3347 (2011/02/23)
(Cyclopentadienyl)tris(acetonitrile)ruthenium hexafluorophosphate {[CpRu(NCMe)3][PF6] or (cyclopentadienyl) (I·6-naphthalene)ruthenium hexafluorophosphate {[CpRu(I·6-naphthalene)][PF6]} in combination with a pyridine oxazoline ligand efficiently catalyze the decarboxylative allylic rearrangement of allyl aryl carbonates. Good levels of regio- and enantioselectivity are obtained. Starting from enantioenriched secondary carbonates, the reaction is stereospecific and the corresponding allylic ethers are obtained with net retention of configuration. An intermolecular version of this transformation was also developed using allyl alkyl carbonates as substrates. Conditions were found to obtain the corresponding products with similar selectivity as in the intramolecular process. Through the use of a hemi-labile hexacoordinated phosphate counterion, a zwitterionic air- and moisture-stable chiral ruthenium complex was synthesized and used in the enantioselective etherification reactions. This highly lipophilic metal complex can be recovered and efficiently reused in subsequent catalysis runs. Copyright
