Palladium complexes, structure

X-ray photoelectron spectroscopy, 144 palladium complexes structure, 144 Diopside structure, 856 Dioxygen activation, 682 biology, 681-711 chemistry, 682 evolution... 

Reaction of the diphosphines Ph2P(CH2) PPh2 (n = 1-3) with MCl2(PhCN)2 affords 1 1 m-complexes (Figure 3.46) [102]. (Note the use of the labile PhCN adducts if the MCl salts are used, Magnus type compounds M(P-P)2+MCl4- are formed.) Similar complexes are formed with other halides for the thiocyanates see section 3.8.6. The structures of the palladium complexes have been determined (Table 3.10) with square coordination only achieved for n = 3 with the formation of a six-membered metal-chelate ring. 

Palladium, polymethylenebis(diphenylphosphine)-bis(thiocyanato)-linkage isomers, 1, 185 Palladium, tetraammine-tetrachloropalladate history, 1, 2 Palladium, tetrachloro-crystal structure, 1, 16 Palladium, tris(dinitrogen)-synthesis, 1,28 Palladium complexes a,(5-dione dioximates electrical properties, 6, 143 acetylacetone hydrolysis, 2,379 alkylperoxo... 

Chitosan (Fig. 27) was deposited on sihca by precipitation. The palladium complex was shown to promote the enantioselective hydrogenation of ketones [80] with the results being highly dependent on the structure of the substrate. In the case of aromatic ketones, both yield and enantioselectiv-ity depend on the N/Pd molar ratio. Low palladium contents favored enan-tioselectivity but reduced the yield. Very high conversions were obtained with aliphatic ketones, although with modest enantioselectivities. More recently, the immobilized chitosan-Co complex was described as a catalyst for the enantioselective hydration of 1-octene [81]. Under optimal conditions, namely Co content 0.5 mmolg and 1-octene/Co molar ratio of 50, a 98% yield and 98% ee were obtained and the catalyst was reused five times without loss of activity or enantioselectivity. 

Over the last decade, the chemistry of the carbon-carbon triple bond has experienced a vigorous resurgence [1]. Whereas construction of alkyne-con-taining systems had previously been a laborious process, the advent of new synthetic methodology based on organotransition metal complexes has revolutionized the field [2]. Specifically, palladium-catalyzed cross-coupling reactions between alkyne sp-carbon atoms and sp -carbon atoms of arenes and alkenes have allowed for rapid assembly of relatively complex structures [3]. In particular, the preparation of alkyne-rich macrocycles, the subject of this report, has benefited enormously from these recent advances. For the purpose of this review, we Emit the discussion to cychc systems which contain benzene and acetylene moieties only, henceforth referred to as phenylacetylene and phenyldiacetylene macrocycles (PAMs and PDMs, respectively). Not only have a wide... 

A bis(stannyl)bis(phosphine)palladium complex has a twisted square planar structure and shows facile unimolecular twist-rotation.170... 

The synthesis, structure, and catalytic properties of a Pd11 complex with a partially hydrogenated ligand, shown in Figure 31, are described.393 This study provides the first asymmetric epoxidation of alkenes catalyzed by a palladium complex.393... 

Figure 3.21 Structure of the dimeric palladium complex [(dppplPdhfCFjSChh. (Reprinted with permission from Organometallics, 1992,11,23. Copyright (1992) American Chemical Society.)...

The reaction of racemic Sb-chiral l-phenyl-2-trimethylsilylstibindole with the optically active ortho-palladated benzylamine derivative, di-p-chlorobis (S)-2-[l-dimethylamino)ethyl]phenyl-C,N dipalladium, leads to diastereomeric complexes which were used for the separation of the enantiomers of the stibindoles.65 The molecular structures of the diastereomeric palladium complexes are depicted in Fig. 4. 

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