Isothiourea-catalysed regioselective acylative kinetic resolution of axially chiral biaryl diols
Abstract
An operationally‐simple isothiourea‐catalyzed acylative kinetic resolution of unprotected 1,1′‐biaryl‐2,2′‐diol derivatives has been developed to allow access to axially chiral compounds in highly enantioenriched form (s values up to 190). Investigation of the reaction scope and limitations provided three key observations: i) the diol motif of the substrate was essential for good conversion and high s values; ii) the use of an α,α‐disubstituted mixed anhydride (2,2‐diphenylacetic pivalic anhydride) was critical to minimize diacylation and give high selectivity; iii) the presence of substituents in the 3,3′‐positions of the diol hindered effective acylation. This final observation was exploited for the highly regioselective acylative kinetic resolution of unsymmetrical biaryl diol substrates bearing a single 3‐substituent. Based on the key observations identified, acylation transition state models have been proposed to explain the atropselectivity of this kinetic resolution.
Citation
Qu , S , Greenhalgh , M D & Smith , A D 2019 , ' Isothiourea-catalysed regioselective acylative kinetic resolution of axially chiral biaryl diols ' , Chemistry - A European Journal , vol. Early View . https://doi.org/10.1002/chem.201805631
Publication
Chemistry - A European Journal
Status
Peer reviewed
ISSN
0947-6539Type
Journal article
Rights
Copyright © 2019 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim. This work has been made available online in accordance with the publisher’s policies. This is the author created accepted version manuscript following peer review and as such may differ slightly from the final published version. The final published version of this work is available at: https://doi.org/10.1002/chem.201805631
Description
The research leading to these results has received funding from the ERC under the European Union's Seventh Framework Programme (FP7/2007-2013)/E.R.C. grant agreement n° 279850. The Chinese Scholarship Scheme and University of St Andrews are thanked for a CSC Scholarship (S.Q.). A.D.S. thanks the Royal Society for a Wolfson Research Merit Award.Collections
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