Carboxylato nickel complexes

A series of thio- 46 [51,168] and seleno-carboxylato complexes 47 [175] with tmns-configurations have been synthesized from the reaction of NiCl2(R3P)2 with alkali metal or 0-trimethylsilyl selenocarboxylates (Scheme 4). Telluro-carboxylato nickel complexes 48 Ni(RCOTe)2(R3P)2 are too labile to isolate, although their formation has been confirmed by their H, and Te NMR and IR spectral data [175]. The anionic thiocarboxylato nickel complex 49 is... 

Nickel(II) complexes with simple carboxylate anions have been well known for a long time,1715 and nickel(II) acetate tetrahydrate is one of the most thoroughly studied compounds. Selected examples of nickel(II) complexes with carboxylate anions are shown in Table 85. The carboxylato complexes are high-spin octahedral with few exceptions. 

Deming and Novak focused their attention on -allylnickel complexes 48 and 49, bearing optically active chiral carboxylato ligands, which would be retained on the nickel center during polymerization (Scheme 38) [62]. The... 

By hydrolysis of the nickel-allyl-carboxylato complexes with mineral acids usually 3-pentene-carboxylic acids are formed [40]. Instead of mineral acids also acetylacetone can be used as displacing agent [44]. 

The reaction between 1,3-dienes and carbon dioxide leads to the formation of carboxylato (ri -allyl)nickel(II) complexes, which may equilibrate with seven-membered ring nickelacycles in which the metal coordinates the allyl in a Ti -fashion (Eq. 5). ... 

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