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1,2-bis(dichlorophosphino)benzene
1,2-Bis(dichlorophosphino)benzene is an organophosphorus compound with the formula C6H4(PCl2)2. A viscous colorless liquid, it is a precursor to chelating diphosphines of the type C6H4(PR2)2. It is prepared from 1,2-dibromobenzene by sequential lithiation followed by treatment with (Et2N)2PCl (Et = ethyl), which affords C6H4 (NEt2)2sub>2. This species is finally cleaved with hydrogen chloride: :C6H4 (NEt2)2sub>2 + 8 HCl → C6H4(PCl2)2 + 4 Et2NH2Cl Related compounds *1,2-Bis(dichlorophosphino)ethane 1,2-Bis(dichlorophosphino)ethane is an organophosphorus compound with the formula (CH2PCl2)2. A colorless liquid, it is a precursor to chelating diphosphines. Synthesis and reactions It is prepared by the reaction of ethylene, white phosphorus, a ... References {{DEFAULTSORT:Bis(dichlorophosphino)benzene, 1,2- Phosphines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bis(diethylamino)chlorophosphine
Bis(diethylamino)chlorophosphine is an organophosphorus compound with the formula (Et2N)2PCl (Et = ethyl). A colorless liquid, it serves as a masked source of PCl2+. Synthesis and reactions The compound is prepared by treatment of phosphorus trichloride with diethylamine: :4 Et2NH + PCl3 → (Et2N)2PCl + 2 Et2NH2Cl Illustrative of its utility is the synthesis of 1,2-bis(dichlorophosphino)benzene. The synthesis involves sequential lithiation of 1,2-dibromobenzene followed by treatment with (Et2N)2PCl:{{cite journal, doi=10.1021/ol010219y, pmid=11735590, title=BINOL-Based Diphosphonites as Ligands in the Asymmetric Rh-Catalyzed Conjugate Addition of Arylboronic Acids, journal=Organic Letters, volume=3, issue=25, pages=4083–4085, year=2001, last1=Reetz, first1=Manfred T., last2=Moulin, first2=Dominique, last3=Gosberg, first3=Andreas :C6H4Br2 + BuLi → C6H4(Br)Li + BuBr :C6H4(Br)Li + (Et2N)2PCl → C6H4(Br)(P(NEt2)2) + LiCl :C6H4(Br)(P(NEt2)2) + BuLi → C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organophosphorus Compound
Organophosphorus compounds are organic compounds containing phosphorus. They are used primarily in pest control as an alternative to chlorinated hydrocarbons that persist in the environment. Some organophosphorus compounds are highly effective insecticides, although some are extremely toxic to humans, including sarin and VX nerve agents. Organophosphorus chemistry is the corresponding science of the properties and reactivity of organophosphorus compounds. Phosphorus, like nitrogen, is in group 15 of the periodic table, and thus phosphorus compounds and nitrogen compounds have many similar properties. The definition of organophosphorus compounds is variable, which can lead to confusion. In industrial and environmental chemistry, an organophosphorus compound need contain only an organic substituent, but need not have a direct phosphorus-carbon (P-C) bond. Thus a large proportion of pesticides (e.g., malathion), are often included in this class of compounds. Phosphorus can adopt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diphosphine
Diphosphane, or diphosphine, is an inorganic compound with the chemical formula P2H4. This colourless liquid is one of several binary phosphorus hydrides. It is the impurity that typically causes samples of phosphine to ignite in air. Properties, preparation, reactions Diphosphane adopts the gauche conformation (like hydrazine, less symmetrical than shown in the image) with a P−P distance of 2.219 angstroms. It is nonbasic, unstable at room temperature, and Pyrophoricity, spontaneously flammable in air. It is only poorly soluble in water but dissolves in organic solvents. Its 1H NMR spectrum consists of 32 lines resulting from an A2XX'A'2 splitting system. Diphosphane is produced by the hydrolysis of calcium monophosphide, which can be described as the Ca2+ derivative of . According to an optimized procedure, hydrolysis of 400 g of CaP at −30 °C gives about 20 g of product, slightly contaminated with phosphine. Reaction of diphosphane with butyllithium affords a varie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2-Dibromobenzene
1,2-Dibromobenzene is an organobromine compound with the formula C6H4Br2. It is one of three isomers, the others being 1,3- and 1,4-dibromobenzene. It is a colorless liquid, although impure samples appear yellowish. The compound is a precursor to many 1,2-disubstituted derivatives of benzene Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms .... For example, it is a precursor to 1,2-dicyanobenzene and dithioethers. See also * 1,3-Dibromobenzene * 1,4-Dibromobenzene References {{DEFAULTSORT:Dibromobenzene, 1,2- Bromoarenes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithiation
In organometallic chemistry, organolithium reagents are chemical compounds that contain carbon–lithium Lithium (from el, λίθος, lithos, lit=stone) is a chemical element with the symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid el ... (C–Li) Chemical bond, bonds. These reagents are important in organic synthesis, and are frequently used to transfer the organic group or the lithium atom to the substrates in synthetic steps, through nucleophilic addition or simple deprotonation. Organolithium reagents are used in industry as an initiator for anionic polymerization, which leads to the production of various elastomers. They have also been applied in asymmetric synthesis in the pharmaceutical industry. Due to the large difference in electronegativity between the carbon atom and the lithium atom, the C−Li bond is highly ionization, ionic. Owing to the polar nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethyl Group
In organic chemistry, an ethyl group (abbr. Et) is an alkyl substituent with the formula , derived from ethane (). ''Ethyl'' is used in the International Union of Pure and Applied Chemistry's nomenclature of organic chemistry for a saturated two-carbon moiety in a molecule, while the prefix "''eth-''" is used to indicate the presence of two carbon atoms in the molecule. Ethylation Ethylation is the formation of a compound by introduction of the ethyl group. The most widely practiced example of this reaction is the ethylation of benzene with ethylene to yield ethylbenzene, a precursor to styrene, which is a precursor to polystyrene. Approximately 24.7 million tons of ethylbenzene were produced in 1999. :: Many ethyl-containing compounds are generated by electrophilic ethylation, i.e. treatment of nucleophiles with sources of Et+. Triethyloxonium tetrafluoroborate t3OF4 is such a reagent. For good nucleophiles, less electrophilic reagents are employed, such as ethyl h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Chloride
The compound hydrogen chloride has the chemical formula and as such is a hydrogen halide. At room temperature, it is a colourless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric water vapor. Hydrogen chloride gas and hydrochloric acid are important in technology and industry. Hydrochloric acid, the aqueous solution of hydrogen chloride, is also commonly given the formula HCl. Reactions Hydrogen chloride is a diatomic molecule, consisting of a hydrogen atom H and a chlorine atom Cl connected by a polar covalent bond. The chlorine atom is much more electronegative than the hydrogen atom, which makes this bond polar. Consequently, the molecule has a large dipole moment with a negative partial charge (δ−) at the chlorine atom and a positive partial charge (δ+) at the hydrogen atom. In part because of its high polarity, HCl is very soluble in water (and in other polar solvents). Upon contact, and HCl combine to form hydronium cations and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2-Bis(dichlorophosphino)ethane
1,2-Bis(dichlorophosphino)ethane is an organophosphorus compound with the formula (CH2PCl2)2. A colorless liquid, it is a precursor to chelating diphosphines. Synthesis and reactions It is prepared by the reaction of ethylene, white phosphorus, and phosphorus trichloride: :3 C2H4 + 0.5 P4 + 4 PCl3 → 3 (CH2PCl2)2 The compound reacts with Grignard reagents and secondary amines to give chelating ligands. An often practiced use of this compound is the synthesis of 1,2-bis(dimethylphosphino)ethane 1,2-Bis(dimethylphosphino)ethane (dmpe) is a diphosphine ligand in coordination chemistry. It is a colorless, air-sensitive liquid that is soluble in organic solvents. With the formula (CHPMe), dmpe is used as a compact strongly basic spectator l .... Related compounds * 1,2-Bis(dichlorophosphino)benzene References {{DEFAULTSORT:Bis(dichlorophosphino)ethane, 1,2- Phosphines 1,2-Ethanediyl compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
