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Title: Asymmetric synthesis of pharmaceutically relevant 1-aryl-2-heteroaryl- and 1,2-diheteroarylcyclopropane-1-carboxylates
This study describes general methods for the enantioselective syntheses of pharmaceutically relevant 1-aryl-2-heteroaryl- and 1,2-diheteroarylcyclopropane-1-carboxylates through dirhodium tetracarboxylate-catalysed asymmetric cyclopropanation of vinyl heterocycles with aryl- or heteroaryldiazoacetates. The reactions are highly diastereoselective and high asymmetric induction could be achieved using either ( R )-pantolactone as a chiral auxiliary or chiral dirhodium tetracarboxylate catalysts. For meta - or para -substituted aryl- or heteroaryldiazoacetates the optimum catalyst was Rh 2 ( R-p -Ph-TPCP) 4 . In the case of ortho -substituted aryl- or heteroaryldiazoacetates, the optimum catalyst was Rh 2 ( R -TPPTTL) 4 . For a highly enantioselective reaction with the ortho -substituted substrates, 2-chloropyridine was required as an additive in the presence of either 4 Å molecular sieves or 1,1,1,3,3,3-hexafluoroisopropanol (HFIP). Under the optimized conditions, the cyclopropanation could be conducted in the presence of a variety of heterocycles, such as pyridines, pyrazines, quinolines, indoles, oxadiazoles, thiophenes and pyrazoles.  more » « less
Award ID(s):
1956154 1700982
PAR ID:
10329965
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Chemical Science
Volume:
12
Issue:
33
ISSN:
2041-6520
Page Range / eLocation ID:
11181 to 11190
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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