In:
European Journal of Inorganic Chemistry, Wiley, Vol. 2005, No. 6 ( 2005-03), p. 1081-1089
Abstract:
The chiral biphenyl‐bridged diimino‐bispyridine ligands N , N ′‐(6,6′‐dimethylbiphenyl‐2,2′‐diyl)bis(2‐pyridylmethyl)‐diimine( 1 )and N , N ′‐(6,6′‐dimethylbiphenyl‐2,2′‐diyl)bis[(6‐methyl‐2‐pyridyl)methyl]diimine ( 2 ) react with Pd(COD)Cl 2 to give, depending on the reaction conditions, either mono‐ or binuclear PdCl 2 complexes. In the binuclear complex 1 ‐(PdCl 2 ) 2 , the Pd nuclei are held at a distance of 3.37 Å by the ligand backbone. N , N ′‐(6,6′‐dimethylbiphenyl‐2,2′‐diyl)bis[(5‐methyl‐2‐furyl)methyl]diimine ( 3 ), with furyl instead of pyridyl rings, gives mononuclear, C 2 ‐ symmetric complexes only. Reactions of [Pd(NCCH 3 ) 4 ] 2+ (BF 4 – ) 2 with ligand 1 or 3 give the C 2 ‐ symmetric cations [ 1 ‐Pd] 2+ or [ 3 ‐Pd(NCCH 3 ) 2 ] 2+ , respectively, as their BF 4 – salts. Solid‐state structures of the chloride complexes 1 ‐PdCl 2 , 1 ‐(PdCl 2 ) 2 and 3 ‐PdCl 2 , and of the complex cations [ 1 ‐Pd] 2+ and [ 3 ‐Pd(NCCCH 3 ) 2 ] 2+ with tetradentate and bidentate ligand coordination, respectively, all show square‐planar coordination, with some distortion toward tedrahedral geometry due to the twisted biaryl‐backbone. Preliminary observations on norbornene polymerization with the catalysts 1 ‐PdCl 2 /MAO, 2 ‐PdCl 2 /MAO and [( 3 ‐Pd(NCCH 3 ) 2 ] 2+ suggest that a certain degree of stereoregularity of the polymers is induced by these chiral catalysts. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Type of Medium:
Online Resource
ISSN:
1434-1948
,
1099-0682
DOI:
10.1002/ejic.v2005:6
DOI:
10.1002/ejic.200400913
Language:
English
Publisher:
Wiley
Publication Date:
2005
detail.hit.zdb_id:
1475009-0
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