Efficient access to cyclic ureas via Pd-catalyzed cyclization

Organic Letters

Volumn 8, Issue 15, 2006, Pages 3311-3314

  McLaughlin, Mark ^a   Palucki, Michael ^a   Davies, Ian W ^a  

^a MERCK RESEARCH LABORATORIES   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BENZIMIDAZOLE DERIVATIVE; DRUG DERIVATIVE; IMIDAZOLE DERIVATIVE; PALLADIUM; PYRIDONE DERIVATIVE; UREA;

ARTICLE; CATALYSIS; CHEMICAL STRUCTURE; CHEMISTRY; COMBINATORIAL CHEMISTRY; CYCLIZATION; SYNTHESIS;

BENZIMIDAZOLES; CATALYSIS; COMBINATORIAL CHEMISTRY TECHNIQUES; CYCLIZATION; IMIDAZOLES; MOLECULAR STRUCTURE; PALLADIUM; PYRIDONES; UREA;

EID: 33746883528     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol061233j     Document Type: Article

References (24)

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20. Notably, the published procedures advocate a "normal" addition protocol, in which CSI is added to the substrate. Based on the observations from the current work, this could account for the moderate yields obtained in these cases.
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23. Again, the mass balance was found in the urea cleavage side reaction, apparently suppressed under the less basic conditions.
24. 2 was also ineffective in attempts to cyclize the bromoaniline substrate.