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1,2-Bis(diisopropylphosphino)ethane
1,2-Bis(diisopropylphosphino)ethane (dippe) is a commonly used bidentate 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 elec ... in coordination chemistry. This compound is similar to the ligand 1,2-bis(diphenylphosphino)ethane (dppe), with the substitution of isopropyl groups for phenyl groups. {{DEFAULTSORT:Bis(diisopropylphosphino)ethane, 1,2- Diphosphines Isopropyl compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diphosphines
Diphosphines, sometimes called bisphosphanes, are organophosphorus compounds most commonly used as bidentate phosphine ligands in inorganic and organometallic chemistry. They are identified by the presence of two phosphino groups linked by a backbone, and are usually chelating. A wide variety of diphosphines have been synthesized with different linkers and R-groups. Alteration of the linker and R-groups alters the electronic and steric properties of the ligands which can result in different coordination geometries and catalytic behavior in homogeneous catalysts. Synthesis 222px, Chlorodiisopropylphosphine is a popular building block for the preparation of diphosphines. From phosphide building blocks Many widely used diphosphine ligands have the general formula Ar2P(CH2)nPAr2. These compounds can be prepared from the reaction of X(CH2)nX (X=halogen) and MPPh2 (M = alkali metal): :Cl(CH2)nCl + 2 NaPPh2 → Ph2P(CH2)nPPh2 + 2 NaCl Diphosphine ligands can also be prepa ... [...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 environment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2-bis(diphenylphosphino)ethane
1,2-Bis(diphenylphosphino)ethane (dppe) is an organophosphorus compound with the formula (PhPCH) (Ph = phenyl). It is a commonly used bidentate ligand in coordination chemistry. It is a white solid that is soluble in organic solvents. Preparation The preparation of dppe is by the alkylation of NaPPh: :P(CH) + 2 Na → NaP(CH) + NaCH NaP(CH), which is readily air-oxidized, is treated with 1,2-dichloroethane (ClCHCHCl) to give dppe: :2 NaP(CH) + ClCHCHCl → (CH)PCHCHP(CH) + 2 NaCl Reactions The reduction of dppe by lithium to give PhHP(CH)PHPh has been reported. :PhP(CH)PPh + 4 Li → PhLiP(CH)PLiPh + 2 PhLi Hydrolysis gives the bis(secondary phosphine): :PhLiP(CH)PLiPh + 2 PhLi + 4HO → PhHP(CH)PHPh + 4 LiOH + 2 CH : Treatment of dppe with conventional oxidants such as hydrogen peroxide (HO), aqueous bromine (Br), etc., produces dppeO in low yield (e.g., 13%) as a result of non-selective oxidation.Encyclopedia of Reagents for Organic Synthesis 2001 John Wiley & Sons, Ltd Sel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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