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Title: Oxidative Mizoroki–Heck reaction of unprotected cinnamylamines at ambient temperature under air
Cinnamylamines make-up many important drugs that target G protein-coupled receptors. While 3,3-diarylallylamines can be prepared via existing synthetic methods, these often require poorly-selective Wittig addition to unsymmetrical ketones, and multistep sequences thereafter to reach the allylamine product. Methods that make use of direct aryl addition to N -protected cinnamylamines via a Mizoroki–Heck pathway are known, however, unprotected cinnamylamines are sensitive to a mixture of C–H activation and Mizoroki–Heck arylation under Pd-catalysed arylation conditions using aryl iodides. This leads to a decrease in the trans / cis selectivity that can be achieved under these reaction conditions. By reimagining the reaction and using aryl boronic acids, we have herein demonstrated how in many cases the yield and E / Z selectivity can be improved. The in situ -formed active catalyst is more sensitive under these conditions, and was observed to shut down at elevated temperatures.  more » « less
Award ID(s):
2047725
PAR ID:
10436812
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Organic Chemistry Frontiers
ISSN:
2052-4129
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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