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Transition Metal Dithiophosphate Complex
Transition metal dithiophosphate complexes are coordination compounds containing dithiophosphate ligands, i.e. ligands of the formula (RO)2PS. The homoleptic complexes have formulas M 2P(OR)2sub>2 and M 2P(OR)2sub>3. These neutral complexes tend to be soluble in organic solvents, especially when R is branched. Perhaps the most important members are zinc dialkyldithiophosphates, which are oil additive Oil additives are chemical compounds that improve the lubricant performance of base oil (or oil "base stock"). The manufacturer of many different oils can utilize the same base stock for each formulation and can choose different additives for each ...s. Such compounds are prepared by the reaction of dialkoxydithiophoric acid with metal oxides, chlorides, and acetates.David E. Coldbery, W. Conard Fernelius, Maurice Shamma, "Chromium(III) O,O′-Diethyl Dithiophosphate" Inorganic Syntheses, 1960 volume 6, pp. 142–143. {{doi, 10.1002/9780470132371.ch44 References Phosphorothio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Compound
A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing compounds, especially those that include transition metals (elements like titanium that belong to the Periodic Table's d-block), are coordination complexes. Nomenclature and terminology Coordination complexes are so pervasive that their structures and reactions are described in many ways, sometimes confusingly. The atom within a ligand that is bonded to the central metal atom or ion is called the donor atom. In a typical complex, a metal ion is bonded to several donor atoms, which can be the same or different. A polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom through several of the ligand's atoms; ligands with 2, 3, 4 or even 6 bonds to the central atom are common. These compl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligand
In coordination chemistry, a ligand is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electron pairs, often through Lewis bases. The nature of metal–ligand bonding can range from covalent to ionic. Furthermore, the metal–ligand bond order can range from one to three. Ligands are viewed as Lewis bases, although rare cases are known to involve Lewis acidic "ligands". Metals and metalloids are bound to ligands in almost all circumstances, although gaseous "naked" metal ions can be generated in a high vacuum. Ligands in a complex dictate the reactivity of the central atom, including ligand substitution rates, the reactivity of the ligands themselves, and redox. Ligand selection requires critical consideration in many practical areas, including bioinorganic and medicinal chemistry, homogeneous catalysis, and environmental chemi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Dialkyldithiophosphate
Zinc dialkyldithiophosphates (often referred to as ZDDP) are a family of coordination compounds developed in the 1940s that feature zinc bound to the anion of a dialkyldithiophosphoric salt (e.g., ammonium diethyl dithiophosphate). These uncharged compounds are not salts. They are soluble in nonpolar solvents, and the longer-chain derivatives easily dissolve in mineral and synthetic oils used as lubricants. They come under CAS number . In aftermarket oil additives, the percentage of ZDDP ranges approximately between 2 and 15%. Zinc dithiophosphates have many names, including ZDDP, ZnDTP, and ZDP. Applications The main application of ZDDPs are as anti-wear additives in lubricants including greases, hydraulic oils, and motor oils. ZDDPs also act as corrosion inhibitors and antioxidants. They are almost ubiquitous in lubricants, and treatment rates are usually between 600 ppm for modern, energy-conserving low-viscosity oils to 2000 ppm of this additive in some racing oils. It has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oil Additive
Oil additives are chemical compounds that improve the lubricant performance of base oil (or oil "base stock"). The manufacturer of many different oils can utilize the same base stock for each formulation and can choose different additives for each specific application. Additives comprise up to 5% by weight of some oils.Thorsten Bartels et al. "Lubricants and Lubrication" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Weinheim. Nearly all commercial motor oils contain additives, whether the oils are synthetic or petroleum based. Essentially, only the American Petroleum Institute (API) Service SA motor oils have no additives, and they are therefore incapable of protecting modern engines. The choice of additives is determined by the application, e.g. the oil for a diesel engine with direct injection in a pickup truck (API Service CJ-4) has different additives than the oil used in a small gasoline-powered outboard motor on a boat (2-cycle engine oil). Types of additives O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dialkoxydithiophoric Acid
Diethyl dithiophosphoric acid, sometimes mistakenly called diethyl dithiophosphate, is the organophosphorus compound with the formula (C2H5O)2PS2H. It is the processor for production of the organophosphate insecticide Terbufos. Although samples can appear dark, it is a colorless liquid.J. Svara, N. Weferling, T. Hofmann "Phosphorus Compounds, Organic" in ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH, Weinheim, 2006. It is prepared by treating phosphorus pentasulfide with ethanol: :P2S5 + 4 C2H5OH → 2 (C2H5O)2PS2H + H2S Reactions : Diethyl- and dimethyl dithiophosphoric acids react with bases. The results of this neutralization reaction are salts, e.g., ammonium diethyl dithiophosphate. Diethyl dithiophosphoric acid reacts with zinc oxide to give zinc dithiophosphate, which is used as an oil additive:H. Spikes "The history and mechanisms of ZDDP" Tribology Letters, Vol. 17, No. 3, October 2004. . :ZnO + 2 (C2H5O)2PS2H → C2H5O)2PS2sub>2Zn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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