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Germanabenzene
Germabenzene (C5H6Ge) is the parent representative of a group of chemical compounds containing in their molecular structure a benzene ring with a carbon atom replaced by a germanium atom. Germabenzene itself has been studied theoretically, and synthesized with a bulky 2,4,6-tris is(trimethylsilyl)methylhenyl or Tbt group. Also, stable naphthalene derivatives do exist in the laboratory such as the 2-germanaphthalene-containing substance represented below. The germanium to carbon bond in this compound is shielded from potential reactants by a Tbt group. This compound is aromatic just as the other carbon group representatives silabenzene and stannabenzene. : See also * 6-membered aromatic rings with one carbon replaced by another group: borabenzene, silabenzene, germabenzene, stannabenzene, pyridine, phosphorine, arsabenzene, bismabenzene, pyrylium, thiopyrylium, selenopyrylium, telluropyrylium Telluropyrylium is an aromatic heterocyclic compound consisting of a six member ring ... [...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, usi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorine
Phosphorine ( IUPAC name: phosphinine) is a heavier element analog of pyridine, containing a phosphorus atom instead of an aza- moiety. It is also called phosphabenzene and belongs to the phosphaalkene class. It is a colorless liquid that is mainly of interest in research. Phosphorine is an air-sensitive oil but is otherwise stable when handled using air-free techniques (however, substituted derivatives can often be handled under air without risk of decomposition). In contrast, silabenzene, a related heavy-element analogue of benzene, is not only air- and moisture-sensitive but also thermally unstable without extensive steric protection. History The first phosphorine to be isolated is 2,4,6-triphenylphosphorine. It was synthesized by Gottfried Märkl in 1966 by condensation of the corresponding pyrylium salt and phosphine or its equivalent ( P(CH2OH)3 and P(SiMe3)3).''G. Märkl'', 2,4,6-Triphenylphosphabenzol iAngewandte Chemie 78, 907–908 (1966)/ref> 500px, Synthesi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germanium(IV) Compounds
Germanium is a chemical element with the symbol Ge and atomic number 32. It is lustrous, hard-brittle, grayish-white and similar in appearance to silicon. It is a metalloid in the carbon group that is chemically similar to its group neighbors silicon and tin. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature. Because it seldom appears in high concentration, germanium was discovered comparatively late in the discovery of the elements. Germanium ranks near fiftieth in relative abundance of the elements in the Earth's crust. In 1869, Dmitri Mendeleev predicted its existence and some of its properties from its position on his periodic table, and called the element ekasilicon. In 1886, Clemens Winkler at Freiberg University found the new element, along with silver and sulfur, in the mineral argyrodite. Winkler named the element after his country, Germany. Germanium is mined primarily from sphalerite (the primary ore of zinc), though germanium is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telluropyrylium
Telluropyrylium is an aromatic heterocyclic compound consisting of a six member ring with five carbon atoms, and a positively charged tellurium atom. Derivatives of telluropyrylium are important in research of infrared dyes. Naming and numbering Formerly it was named tellurapyrylium. However this is misleading, as "tellura" indicates that tellurium substitutes for carbon atom, but actually tellurium is substituted for the oxygen atom in pyrilium. In the Hantzsch-Widman system it is called tellurinium. This is the name used by Chemical Abstracts. Replacement nomenclature would call this telluroniabenzene. Numbering in telluropyrylium starts with 1 on the tellurium atom and counts up to 6 counter-clockwise on the carbon atoms. The positions adjacent to the chalcogen, numbered 2 and 6 can also be called α, the next two positions 3 and 5 can be termed "β" and the opposite carbon at position 4 can be called "γ". Occurrence Because telluropyrylium is a positively charged cation, it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenopyrylium
Selenopyrylium is an aromatic heterocyclic compound consisting of a six-membered ring with five carbon atoms and a positively charged selenium atom. Naming and numbering Formerly it was named selenapyrylium. However, this is misleading as "selena" indicates that selenium substitutes for a carbon atom, but actually selenium is substituted for the oxygen atom in pyrylium. In the Hantzsch-Widman system of nomenclature, it is called seleninium. This is the name used by Chemical Abstracts. Replacement nomenclature would call this selenoniabenzene. Numbering in selenopyrylium starts with 1 on the selenium atom and counts up to 6 on the carbon atoms. The positions adjacent to the chalcogen, numbered 2 and 6 can also be called α, the next two positions 3 and 5 can be termed "β" and the opposite carbon at position 4 can be called "γ". Occurrence Because selenopyrylium is a positively charged ion, it takes the solid form as a salt with non-nucleophillic anions such as perchlorate, tetra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiopyrylium
Thiopyrylium is a cation with the chemical formula C5H5S+. It is analogous to the pyrylium cation with the oxygen atom replaced by a sulfur atom. Thiopyrylium salts are less reactive than the analogous pyrylium salts due to the higher polarizability of the sulfur atom. Among the chalcogenic 6-membered unsaturated heterocycles, thiopyrylium is the most aromatic, due to sulfur having the similar Pauling electronegativity as carbon and only a slightly higher covalent radius. In water, thiopyrylium reacts to it and forms a mixture of 2-hydroxythiopyran and 4-hydroxythiopyran. Thiopyrylium salts can be synthesized by hydrogen abstraction from thiopyran by a hydride ion acceptor, such as trityl perchlorate. The thiopyrylium analogue of 2,4,6-trisubstituted pyrylium salts can be synthesized by treatment with sodium sulfide followed by precipitation with acid. This reaction causes the oxygen atom in the pyrylium cation to be substituted with sulfur. See also * 6-membered aromatic r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrylium
Pyrylium is a cation (positive ion) with formula , consisting of a six-membered ring of five carbon atoms, each with one hydrogen atom, and one positively charged oxygen atom. The bonds in the ring are conjugated as in benzene, giving it an aromatic character. In particular, because of the positive charge, the oxygen atom is trivalent. Pyrilium is a mono-cyclic and heterocyclic compound, one of the oxonium ions. Salts Pyrylium and its derivatives form stable salts with a variety of anions. Derivatives Many important cations are formally derived from pyrylium by substitution of various functional groups for some or all the hydrogens in the ring. The 2,4,6-triphenylpyrilium, referred to as the Katritzky salt, (after Alan R. Katritzky) is an important example used in many modern examples of metal catalyzed cross-couplings. Chemical properties Like other oxonium ions, pyrylium is unstable in neutral water. However, pyrylium is much less reactive than ordinary oxonium ions bec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bismabenzene
Bismabenzene () is the parent representative of a group of organobismuth compounds that are related to benzene with a carbon atom replaced by a bismuth Bismuth is a chemical element with the symbol Bi and atomic number 83. It is a post-transition metal and one of the pnictogens, with chemical properties resembling its lighter group 15 siblings arsenic and antimony. Elemental bismuth occurs ... atom. Bismabenzene itself has been synthesised but not isolated because it is too reactive, tending to instead dimerize in a Diels-Alder addition. An unstable derivative with 4-alkyl substituents was reported in 1982. A stable derivative was reported in 2016. This derivative has two tri(isopropyl)silyl substituents in the ''ortho''-positions and was synthesized from aluminacyclohexadiene, bismuth trichloride, and DBU. References {{reflist, colwidth=30em, refs= {{cite journal , doi = 10.1021/jacs.6b08714, title = An Isolable Bismabenzene: Synthesis, Structure, and Reactivit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsabenzene
Arsabenzene (IUPAC name: arsinine) is an organoarsenic heterocyclic compound with the chemical formula C5H5As. It belongs to a group of compounds called heteroarenes that have the general formula C5H5E (E= N, P, As, Sb, Bi). This air sensitive liquid has an onion odor, and it decomposes on heating. Arsabenzene is also an ambidentate ligand that prefers to coordinate using η1(As)- or η6(π)-routes. The study of arsabenzene and related compounds was an important step in the understanding of compounds that contain multiple bonds between carbon and heavier elements. The study of heteroarenes was begun by Märkl, with the synthesis of 2,4,6-triphenylphosphabenzene. This is achieved by treating 2,4,6-trisubstituted pyrylium salt with phosphanes. The first derivative of arsabenzene was 9-arsaanthracene prepared by Jutzi and Bickelhaupt. Structure Arsabenzene is planar. The C—C bond distances of 1.39 Å, the As—C bond has a length of 1.85 Å, this is 6.6% shorter than the no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyridine
Pyridine is a basic (chemistry), basic heterocyclic compound, heterocyclic organic compound with the chemical formula . It is structurally related to benzene, with one methine group replaced by a nitrogen atom. It is a highly flammable, weakly alkaline, water-miscible liquid with a distinctive, unpleasant fish-like smell. Pyridine is colorless, but older or impure samples can appear yellow, due to the formation of extended, unsaturated polymeric chains, which show significant electrical conductivity. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Historically, pyridine was produced from coal tar. As of 2016, it is synthesized on the scale of about 20,000 tons per year worldwide. Properties Physical properties The molecular electric dipole moment is 2.2 debyes. Pyridine is diamagnetism, diamagnetic and has a Magnetic susceptibility, diamagnetic susceptibility of −48.7 × 10−6 cm3·mol−1. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
