Palladium-catalyzed coupling of vinylogous amides with aryl halides: Applications to the synthesis of heterocycles

Organic Letters

Volumn 2, Issue 8, 2000, Pages 1109-1112

  Edmondson, Scott D ^a   Mastracchio, Anthony ^a   Parmee, Emma R ^a  

^a MERCK RESEARCH LABORATORIES   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0000594028     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol000031z     Document Type: Article

References (40)

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18. 13C NMR and LC-MS.
19. Recently made commercially available by Strem Chemical Co.
20. 4 was ineffective as a catalyst.
21. Control experiments in which the optimized conditions were applied to the reaction of 1 with 2b in the absence of either palladium or ligand 4 failed to produce 3b. Reactions in Tables 1 and 2 were not optimized with respect to reaction times.
22. It should be noted that the deprotected version of 2p (without the Boc) did not undergo a coupling reaction with 1.
23. 2) followed by Mosher amide analysis of the resulting amine indicated 33% ee of product.
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26. As before, a 33% ee was observed in 8e by chiral HPLC (ChiralPak AS column, 1:3 alcohol/hexanes). Also, no coupling was observed with the deprotected version of 2o.
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36. 4 reduction.
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40. 2, 80% EtOAc/hexanes) to afford 3d (88 mg, 77%) as a waxy yellow solid.