Premium
Tripodal Oxygen Ligand Supported Palladium(II) Complexes: Alkylation, Carboxymethylation, and CO Insertion Reactions – X‐ray Crystal Structure Determination of [PdL 2 ], L – = [(C 5 H 5 )Co{P(O)(OMe) 2 } 3 ] – , a Novel Homoleptic Oxygen Ligand Palladium Complex
Author(s) -
Kläui Wolfgang,
Glaum Marcus,
Hahn Ekkehardt,
Lügger Thomas
Publication year - 2000
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/(sici)1099-0682(200001)2000:1<21::aid-ejic21>3.0.co;2-x
Subject(s) - chemistry , homoleptic , palladium , ligand (biochemistry) , protonation , crystal structure , medicinal chemistry , alkylation , stereochemistry , crystallography , catalysis , metal , organic chemistry , biochemistry , receptor , ion
The reaction of [PdCl 2 (CH 3 CN) 2 ] with the silver salt of the tripodal oxygen ligand L – = [(C 5 H 5 )Co{P(O)(OMe) 2 )} 3 ] – yields the homoleptic oxygen ligand complex [PdL 2 ] ( 1 ). The molecular structure of 1 was determined by single‐crystal X‐ray diffraction: monoclinic space group P 2 1 / n ; a = 8.515(1), b = 13.627(2), c = 15.828(2) Å; β = 92.44(1)°; V = 1834.9(7) Å 3 ; Z = 2. The complexes [Pd(PPh 3 )XL] [X = Cl ( 2a ), Br ( 2b ), I ( 2c )] have been prepared starting from 1 . Complex 2a reacts with PPh 3 to form [Pd(PPh 3 ) 2 L]Cl ( 3a ) and [Pd(PPh 3 ) 2 L]L ( 3b ). Treatment of 2a with CO in MeOH yields the carboxymethyl complex [{(PPh 3 )(COOMe)Pd(μ‐Cl)} 2 ] ( 4 ) and the protonated ligand HL. The carboxymethyl complex 4 shows some catalytic activity for the copolymerization of CO and ethene. Complex 4 reacts with AgL to yield [Pd(PPh 3 )(COOMe)L] ( 6 ). Alkylation of 2a with Me 4 Sn leads to the methyl complexes [Pd(PPh 3 )MeL] ( 7 ) and [Me 2 ClSnL] ( 8 ). CO insertion in the palladium–carbon bond of 7 gives the stable acetyl complex [Pd(PPh 3 ){C(O)Me}L] ( 10 ). The palladium(II) complexes 1 , 2 , 3 , 6 , 7 , and 10 of the tripodal oxygen ligand L are all fluxional molecules that have been studied by temperature‐dependent 1 H‐ and 31 P‐NMR spectroscopy.