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Common Lewis acid catalysts are based on main group metals such as aluminum, boron, silicon, and tin, as well as many early (titanium, zirconium) and late (iron, copper, zinc) d-block metals. The metal atom forms an adduct with a lone-pair bearing electronegative atom in the substrate, such as oxygen (both sp 2 or sp 3), nitrogen, sulfur, and ...
Many methods allow the synthesis of metal carboxylates. From preformed carboxylic acid, the following routes have been demonstrated: [5] acid-base reactions: L n MOR' + RCO 2 H → L n MO 2 CR + R'OH protonolysis: L n Malkyl + RCO 2 H → L n MO 2 CR + alkane oxidative addition: L n M + RCO 2 H → L n (H)MO 2 CR
When the metal is square planar, these complexes can exist as cis and trans isomers. The stereochemical possibilities increase when the amino acid ligands are not homochiral. Homoleptic complexes are also known where the amino carboxylate is tridentate amino acids. One such complex is Ni(κ 3-histidinate) 2.
The synthesis of ionic carbonyl complexes is possible by oxidation or reduction of the neutral complexes. Anionic metal carbonylates can be obtained for example by reduction of dinuclear complexes with sodium. A familiar example is the sodium salt of iron tetracarbonylate (Na 2 Fe(CO) 4, Collman's reagent), which is used in organic synthesis. [47]
In organic chemistry, the Arndt–Eistert reaction is the conversion of a carboxylic acid to its homologue. It is named for the German chemists Fritz Arndt (1885–1969) and Bernd Eistert (1902–1978). The method entails treating an acid chlorides with diazomethane. It is a popular method of producing β-amino acids from α-amino acids. [1]
Metallacarboxylic acids mainly arise by the attack of hydroxide on electrophilic metal carbonyl complexes. An illustrative synthesis is the reaction of a cationic iron carbonyl with a stoichiometric amount of base: [2] [(C 5 H 5)(CO) 2 FeCO]BF 4 + NaOH → [(C 5 H 5)(CO) 2 FeCO 2 H + NaBF 4
The Suzuki reaction or Suzuki coupling is an organic reaction that uses a palladium complex catalyst to cross-couple a boronic acid to an organohalide. [1] [2] [3] It was first published in 1979 by Akira Suzuki, and he shared the 2010 Nobel Prize in Chemistry with Richard F. Heck and Ei-ichi Negishi for their contribution to the discovery and development of noble metal catalysis in organic ...
Examples include the synthesis of ammonium chloride from organic substances as described in the works (c. 850–950) attributed to Jābir ibn Ḥayyān, [4] or the production of mineral acids such as sulfuric and nitric acids by later alchemists, starting from c. 1300. [5]