In:
European Journal of Inorganic Chemistry, Wiley, Vol. 2004, No. 13 ( 2004-07), p. 2706-2715
Abstract:
The binuclear hydroxo complex [NBu 4 ] 2 [Pd 2 {C 4 (COOMe) 4 } 2 (μ‐OH) 2 ] ( 1 ) has been prepared by addition of two equivalents of NBu 4 OH to polymeric [Pd{C 4 (COOMe) 4 }] n . Complex 1 has been successfully employed as a precursor to three novel binuclear imidate‐bridged complexes [NBu 4 ] 2 [Pd 2 {C 4 (COOMe) 4 } 2 (μ‐imidate) 2 ] [imidate = succinimidate (suc) 2 , phthalimidate (pht) 3 or maleimidate (mal) 4 ] in which the imidate group displays a bidentate N , O ‐coordination mode. The hemilabile behaviour of the imidate ligands has been investigated by reaction with a variety of P, N and S ligands, affording the corresponding mononuclear derivatives [NBu 4 ][Pd{C 4 (COOMe) 4 }(imidate)L] [L = PPh 3 ( 2a , 3a or 4a ), P( p ‐C 6 H 4 F) 3 ( 2b , 3b or 4b ), PBu 3 ( 2c , 3c or 4c ), py ( 2d , 3d or 4d ), p ‐MeC 6 H 4 NH 2 ( 2e , 3e or 4e ), tetrahydrothiophene ( 2f , 3f or 4f )] with terminal N ‐bonded imidate ligands. The characterization of the new complexes involved spectroscopic methods (IR, FAB, 1 H, 13 C, 19 F and 31 P NMR) and X‐ray crystallographic analysis for 1 , 4b and 4e . The mononuclear derivatives are shown to catalyse the Stille cross‐coupling of benzyl bromide 7 with ethyl Z ‐vinylstannyl carboxylate ( 8 ) in high yields. Yields and reaction times are dependent on the presence and type of imidate ligand, which suggests an important role for it in the catalytic cycle. (© Wiley‐VCH Verlag GmbH and Co. KGaA, 69451 Weinheim, Germany, 2004)
Type of Medium:
Online Resource
ISSN:
1434-1948
,
1099-0682
DOI:
10.1002/ejic.v2004:13
DOI:
10.1002/ejic.200300962
Language:
English
Publisher:
Wiley
Publication Date:
2004
detail.hit.zdb_id:
1475009-0
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