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Most Requested Journal Articles 2Q05-Chemistry and Related
Following is one of the journal articles most requested by researchers using CAS online services.
CAPLUS COPYRIGHT 2005 ACS on STN
Suzuki-Miyaura coupling reactions of aryl and heteroaryl halides with aryl-, heteroaryl- and vinylboronic acids proceed in very good to excellent yield with the use of 2-(2',6'-dimethoxybiphenyl)dicyclohexylphosphine, SPhos (1) (I). This ligand confers unprecedented activity for these processes, allowing reactions to be performed at low catalyst levels, to prep. extremely hindered biaryls and to be carried out, in general, for reactions of aryl chlorides at room temp. Addnl., structural studies of various 1.cntdot.Pd complexes are presented along with computational data that help elucidate the efficacy that 1 imparts on Suzuki-Miyaura coupling processes. Moreover, a comparison of the reactions with 1 and with 2-(2',4',6'-triisopropylbiphenyl)diphenylphosphine (2) (II) is presented that is informative in detg. the relative importance of ligand bulk and electron-donating ability in the high activity of catalysts derived from ligands of this type. Further, when the aryl bromide becomes too hindered, an interesting C-H bond functionalization-cross-coupling sequence intervenes to provide product in high yield. View the full-text pdf document from the American Chemical Society, a participating ChemPort publisher.
Updated 5/8/2007 10:39:54 AM
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