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Triphenylstibine
Triphenylstibine is the chemical compound with the formula Sb(C6H5)3. Abbreviated SbPh3, this colourless solid is often considered the prototypical organoantimony compound. It is used as a ligand in coordination chemistry and as a reagent in organic synthesis. Like the related molecules triphenylphosphine and triphenylarsine, SbPh3 is pyramidal with a propeller-like arrangement of the phenyl groups. The Sb-C distances average 2.14-2.17 Å and the C-Sb-C angle are 95°. SbPh3 was first reported in 1886, being prepared from antimony trichloride by the reaction: :6 Na + 3 C6H5Cl + SbCl3 → (C6H5)3Sb + 6 NaCl An alternative method treats phenylmagnesium bromide Phenylmagnesium bromide, with the simplified formula , is a magnesium-containing organometallic compound. It is commercially available as a solution in diethyl ether or tetrahydrofuran (THF). Phenylmagnesium bromide is a Grignard reagent. It is o ... with SbCl3. References {{reflist Organoantimony compounds Phenyl c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organoantimony Compounds
Organoantimony chemistry is the chemistry of compounds containing a carbon to antimony (Sb) chemical bond. Relevant oxidation states are Sb(V) and Sb(III). The toxicity of antimony limits practical application in organic chemistry. Organoantimony(V) chemistry Antimony compounds of the type R5Sb (stiboranes) can be synthesised from trivalent Sb precursors: :Ph3Sb + Cl2 → Ph3SbCl2 :Ph3SbCl2 + 2 PhLi → Ph5Sb Asymmetric compounds can also be obtained through the stibonium ion: :R5Sb + X2 → 4Sbsup>+ : 4Sbsup>+ + R'MgX → R4R'Sb Just as in the related organobismuth compounds (same group 15), organoantimony(V) compounds form onium compounds and ate complexes. Pentaphenylantimony decomposes at 200 °C to triphenylstibine and biphenyl. It forms a trigonal bipyramidal molecular geometry. In the related Me5Sb all methyl protons are equivalent at -100 °C in proton NMR. Compounds of the type R4SbX tend to form dimers. Organoantimony(III) chemistry Comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trigonal Pyramidal
In chemistry, a trigonal pyramid is a molecular geometry with one atom at the apex and three atoms at the corners of a trigonal base, resembling a tetrahedron (not to be confused with the tetrahedral geometry). When all three atoms at the corners are identical, the molecule belongs to point group ''C3v''. Some molecules and ions with trigonal pyramidal geometry are the pnictogen hydrides (XH3), xenon trioxide (XeO3), the chlorate ion, , and the sulfite ion, . In organic chemistry, molecules which have a trigonal pyramidal geometry are sometimes described as sp3 hybridized. The AXE method for VSEPR theory states that the classification is AX3E1. Trigonal pyramidal geometry in ammonia The nitrogen in ammonia has 5 valence electrons and bonds with three hydrogen atoms to complete the octet. This would result in the geometry of a regular tetrahedron with each bond angle equal to cos−1(−) ≈ 109.5°. However, the three hydrogen atoms are repelled by the electr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylphosphine
Triphenylphosphine (IUPAC name: triphenylphosphane) is a common organophosphorus compound with the formula P(C6H5)3 and often abbreviated to P Ph3 or Ph3P. It is widely used in the synthesis of organic and organometallic compounds. PPh3 exists as relatively air stable, colorless crystals at room temperature. It dissolves in non-polar organic solvents such as benzene and diethyl ether. Preparation and structure Triphenylphosphine can be prepared in the laboratory by treatment of phosphorus trichloride with phenylmagnesium bromide or phenyllithium. The industrial synthesis involves the reaction between phosphorus trichloride, chlorobenzene, and sodium: :PCl3 + 3 PhCl + 6 Na → PPh3 + 6 NaCl Triphenylphosphine crystallizes in triclinic and monoclinic modification. In both cases, the molecule adopts a pyramidal structure with propeller-like arrangement of the three phenyl groups. Principal reactions with chalcogens, halogens, and acids Oxidation Triphenylphosphine undergoes slow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylarsine
Triphenylarsine is the chemical compound with the formula As(C6H5)3. This organoarsenic compound, often abbreviated As Ph3, is a colorless crystalline solid that is used as a ligand and a reagent in coordination chemistry and organic synthesis. The molecule is pyramidal with As-C distances of 1.942–1.956 Å and C-As-C angles of 99.6–100.5°. This compound is prepared by the reaction of arsenic trichloride with chlorobenzene using sodium as the reducing agent: :AsCl3 + 3 PhCl + 6 Na → AsPh3 + 6 NaCl Reactions Reaction of triphenylarsine with lithium gives lithium diphenylarsenide: :AsPh3 + 2 Li → LiAsPh2 + LiPh Triphenylarsine is the precursor to tetraphenylarsonium chloride, sPh4l, a popular precipitating agent. AsPh3 forms metal complexes with metals. Most are analogues of the corresponding triphenylphosphine derivatives. Examples include IrCl(CO)(AsPh3)2, RhCl(AsPh3)3, and Fe(CO)4(AsPh3). Tetraphenylarsonium chloride Tetraphenylarsonium chloride is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stibine
Stibine (IUPAC name: stibane) is a chemical compound with the formula SbH3. A pnictogen hydride, this colourless, highly toxic gas is the principal covalent hydride of antimony, and a heavy analogue of ammonia. The molecule is pyramidal with H–Sb–H angles of 91.7° and Sb–H distances of 170.7 pm (1.707 Å). This gas has an offensive smell like hydrogen sulfide (rotten eggs). Preparation SbH3 is generally prepared by the reaction of Sb3+ sources with H− equivalents: :2 Sb2O3 + 3 LiAlH4 → 4 SbH3 + 1.5 Li2O + 1.5 Al2O3 :4 SbCl3 + 3 NaBH4 → 4 SbH3 + 3 NaCl + 3 BCl3 Alternatively, sources of Sb3− react with protonic reagents (even water) to also produce this unstable gas: :Na3Sb + 3 H2O → SbH3 + 3 NaOH Properties The chemical properties of SbH3 resemble those for AsH3. Typical for a heavy hydride (e.g. AsH3, H2Te, SnH4), SbH3 is unstable with respect to its elements. The gas decomposes slowly at room temperature but rapidly at 200 °C: ::2 SbH3 → 3 H2 + 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken and/or new bonds formed. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, using the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Formula
In chemistry, a chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and ''plus'' (+) and ''minus'' (−) signs. These are limited to a single typographic line of symbols, which may include Subscript and superscript, subscripts and superscripts. A chemical formula is not a chemical nomenclature, chemical name, and it contains no words. Although a chemical formula may imply certain simple chemical structures, it is not the same as a full chemical structural formula. Chemical formulae can fully specify the structure of only the simplest of molecules and chemical substances, and are generally more limited in power than chemical names and structural formulae. The simplest types of chemical formulae are called ''empirical formulae'', which use letters and numbers ind ... [...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] |
Coordination Chemistry
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] |
Organic Synthesis
Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one of the most important branches of organic chemistry. There are several main areas of research within the general area of organic synthesis: ''total synthesis'', ''semisynthesis'', and ''methodology''. Total synthesis A total synthesis is the complete chemical synthesis of complex organic molecules from simple, commercially available petrochemical or natural precursors. Total synthesis may be accomplished either via a linear or convergent approach. In a ''linear'' synthesis—often adequate for simple structures—several steps are performed one after another until the molecule is complete; the chemical compounds made in each step are called synthetic intermediates. Most often, each step in a synthesis refers to a separate rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylphosphine
Triphenylphosphine (IUPAC name: triphenylphosphane) is a common organophosphorus compound with the formula P(C6H5)3 and often abbreviated to P Ph3 or Ph3P. It is widely used in the synthesis of organic and organometallic compounds. PPh3 exists as relatively air stable, colorless crystals at room temperature. It dissolves in non-polar organic solvents such as benzene and diethyl ether. Preparation and structure Triphenylphosphine can be prepared in the laboratory by treatment of phosphorus trichloride with phenylmagnesium bromide or phenyllithium. The industrial synthesis involves the reaction between phosphorus trichloride, chlorobenzene, and sodium: :PCl3 + 3 PhCl + 6 Na → PPh3 + 6 NaCl Triphenylphosphine crystallizes in triclinic and monoclinic modification. In both cases, the molecule adopts a pyramidal structure with propeller-like arrangement of the three phenyl groups. Principal reactions with chalcogens, halogens, and acids Oxidation Triphenylphosphine undergoes slow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylarsine
Triphenylarsine is the chemical compound with the formula As(C6H5)3. This organoarsenic compound, often abbreviated As Ph3, is a colorless crystalline solid that is used as a ligand and a reagent in coordination chemistry and organic synthesis. The molecule is pyramidal with As-C distances of 1.942–1.956 Å and C-As-C angles of 99.6–100.5°. This compound is prepared by the reaction of arsenic trichloride with chlorobenzene using sodium as the reducing agent: :AsCl3 + 3 PhCl + 6 Na → AsPh3 + 6 NaCl Reactions Reaction of triphenylarsine with lithium gives lithium diphenylarsenide: :AsPh3 + 2 Li → LiAsPh2 + LiPh Triphenylarsine is the precursor to tetraphenylarsonium chloride, sPh4l, a popular precipitating agent. AsPh3 forms metal complexes with metals. Most are analogues of the corresponding triphenylphosphine derivatives. Examples include IrCl(CO)(AsPh3)2, RhCl(AsPh3)3, and Fe(CO)4(AsPh3). Tetraphenylarsonium chloride Tetraphenylarsonium chloride is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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