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Pentafluorothiophenol
Pentafluorothiophenol is an organosulfur compound with the formula . It is a colorless volatile liquid. The compound is prepared by the reaction of sodium hydrosulfide and hexafluorobenzene. With a p''K''a of 2.68, it is one of the most acidic thiols. Its conjugate base has been used as a ligand in coordination chemistry.Torrens, Hugo "Pentafluorobenzenethiolato derivatives of the platinum group metals" Coordination Chemistry Reviews, 2000, vol. 196, pp. 331-352. {{doi, 10.1016/S0010-8545(99)00055-7 Related compounds * Pentafluorophenol Pentafluorophenol is the organofluorine compound (specifically a fluoroalcohol) with the formula . This is the perfluorinated analogue of phenol. It is a white solid that melts just above room temperature, and smells of phenol. With a pKa, p''K''a ... References Thiols Fluoroarenes Foul-smelling chemicals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexafluorobenzene
Hexafluorobenzene, HFB or perfluorobenzene is an organofluorine compound with the chemical formula . In this derivative of benzene, all hydrogen atoms have been replaced by fluorine atoms. The technical uses of the compound are limited, although it has some specialized uses in the laboratory owing to distinctive spectroscopic properties. Geometry of the aromatic ring Hexafluorobenzene stands somewhat aside in the perhalogenbenzenes. If a perhalogenated benzene ring were to remain planar, then geometric constraints would force adjacent halogens closer than their associated nonbonding radius. Consequently the benzene ring buckles, reducing ''p''-orbital overlap and aromaticity to avoid the steric clash. Perfluorobenzene is an exception: as shown in the following table, two fluorines are small enough to avoid collision, retaining planarity and full aromaticity. Synthesis The direct synthesis of hexafluorobenzene from benzene and fluorine has not been useful. Instead it is pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiol
In organic chemistry, a thiol (; ), or thiol derivative, is any organosulfur compound of the form , where R represents an alkyl or other organic substituent. The functional group itself is referred to as either a thiol group or a sulfhydryl group, or a sulfanyl group. Thiols are the sulfur analogue of alcohols (that is, sulfur takes the place of oxygen in the hydroxyl () group of an alcohol), and the word is a blend of "''thio-''" with "alcohol". Many thiols have strong odors resembling that of garlic, cabbage or rotten eggs. Thiols are used as odorants to assist in the detection of natural gas (which in pure form is odorless), and the smell of natural gas is due to the smell of the thiol used as the odorant. Nomenclature Thiols are sometimes referred to as mercaptans () or mercapto compounds, a term introduced in 1832 by William Christopher Zeise and is derived from the Latin ('capturing mercury')''Oxford American Dictionaries'' (Mac OS X Leopard). because the thiolate grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organosulfur Compound
Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur derivatives, e.g., saccharin. Nature is abound with organosulfur compounds—sulfur is vital for life. Of the 20 common amino acids, two ( cysteine and methionine) are organosulfur compounds, and the antibiotics penicillin and sulfa drugs both contain sulfur. While sulfur-containing antibiotics save many lives, sulfur mustard is a deadly chemical warfare agent. Fossil fuels, coal, petroleum, and natural gas, which are derived from ancient organisms, necessarily contain organosulfur compounds, the removal of which is a major focus of oil refineries. Sulfur shares the chalcogen group with oxygen, selenium, and tellurium, and it is expected that organosulfur compounds have similarities with carbon–oxygen, carbon–selenium, and car ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hydrosulfide
Sodium hydrosulfide is the chemical compound with the formula NaSH. This compound is the product of the half-neutralization of hydrogen sulfide () with sodium hydroxide (NaOH). NaSH and sodium sulfide are used industrially, often for similar purposes. Solid NaSH is colorless. The solid has an odor of owing to hydrolysis by atmospheric moisture. In contrast with sodium sulfide (), which is insoluble in organic solvents, NaSH, being a 1:1 electrolyte, is more soluble. Structure and properties Crystalline NaSH undergoes two phase transitions. At temperatures above 360 K, NaSH adopts the NaCl structure, which implies that the behaves as a spherical anion owing to its rapid rotation, leading to equal occupancy of eight equivalent positions. Below 360 K, a rhombohedral structure forms, and the sweeps out a discoidal shape. Below 114 K, the structure becomes monoclinic. The analogous rubidium and potassium compounds behave similarly. NaSH has a relatively low melting p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conjugate Base
A conjugate acid, within the Brønsted–Lowry acid–base theory, is a chemical compound formed when an acid gives a proton () to a base—in other words, it is a base with a hydrogen ion added to it, as it loses a hydrogen ion in the reverse reaction. On the other hand, a conjugate base is what remains after an acid has donated a proton during a chemical reaction. Hence, a conjugate base is a substance formed by the removal of a proton from an acid, as it can gain a hydrogen ion in the reverse reaction. Because some acids can give multiple protons, the conjugate base of an acid may itself be acidic. In summary, this can be represented as the following chemical reaction: \text + \text \; \ce \; \text + \text Johannes Nicolaus Brønsted and Martin Lowry introduced the Brønsted–Lowry theory, which said that any compound that can give a proton to another compound is an acid, and the compound that receives the proton is a base. A proton is a subatomic particle in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligand
In coordination chemistry, a ligand is an ion or molecule with a 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 acids and bases, Lewis bases. The nature of metal–ligand bonding can range from covalent bond, covalent to ionic bond, 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 acids and bases, 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 (chemistry), 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 are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Chemistry
A coordination complex is a chemical compound consisting of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of chemical bond, bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing chemical compound, 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 Ligand#Polydentate and polyhapto ligand motifs and nomenclature, polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentafluorophenol
Pentafluorophenol is the organofluorine compound (specifically a fluoroalcohol) with the formula . This is the perfluorinated analogue of phenol. It is a white solid that melts just above room temperature, and smells of phenol. With a pKa, p''K''a of 5.5, it is one of the most acidic phenols. Uses Pentafluorophenol is used to prepare pentafluorophenyl esters, which are active esters useful in peptide synthesis. Environmental hazards Pentafluorophenol is considered hazardous because of oral, dermal and inhalation toxicity and because it causes severe skin burns and eye damage. References {{Reflist Fluoroarenes Perfluorinated compounds Phenols ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluoroarenes
In organic chemistry, an aryl halide (also known as a haloarene) is an aromatic compound in which one or more hydrogen atoms directly bonded to an aromatic ring are replaced by a halide ion (such as fluorine F''−'', chlorine Cl−1,−3,−5, bromine Br−1, or iodine I−). Aryl halides are distinct from haloalkanes (alkyl halides) due to significant differences in their methods of preparation, chemical reactivity, and physical properties. The most common and important members of this class are aryl chlorides, but the group encompasses a wide range of derivatives with diverse applications in organic synthesis, pharmaceuticals, and materials science. Classification according to halide Aryl fluorides Aryl fluorides are used as synthetic intermediates, e.g. for the preparation of pharmaceuticals, pesticides, and liquid crystals. The conversion of diazonium salts is a well established route to aryl fluorides. Thus, anilines are precursors to aryl fluorides. In the classic Schiemann ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
