Half sandwich compoundHalf sandwich compounds, also known as piano stool complexes, are organometallic complexes that feature a cyclic polyhapto ligand bound to an MLn center, where L is a unidentate ligand. Thousands of such complexes are known. Well-known examples include cyclobutadieneiron tricarbonyl and (C5H5)TiCl3. Commercially useful examples include (C5H5)Co(CO)2, which is used in the synthesis of substituted pyridines, and methylcyclopentadienyl manganese tricarbonyl, an antiknock agent in petrol. MMT-2D-skeletal.
Arene substitution patternArene substitution patterns are part of organic chemistry IUPAC nomenclature and pinpoint the position of substituents other than hydrogen in relation to each other on an aromatic hydrocarbon. Electrophilic aromatic substitution In ortho-substitution, two substituents occupy positions next to each other, which may be numbered 1 and 2. In the diagram, these positions are marked R and ortho. In meta-substitution the substituents occupy positions 1 and 3 (corresponding to R and meta in the diagram).
SubstituentIn organic chemistry, a substituent is one or a group of atoms that replaces (one or more) atoms, thereby becoming a moiety in the resultant (new) molecule. (in organic chemistry and biochemistry, the terms substituent and functional group, as well as side chain and pendant group, are used almost interchangeably to describe those branches from the parent structure, though certain distinctions are made in polymer chemistry. In polymers, side chains extend from the backbone structure.
Alkyl groupIn organic chemistry, an alkyl group is an alkane missing one hydrogen. The term alkyl is intentionally unspecific to include many possible substitutions. An acyclic alkyl has the general formula of . A cycloalkyl group is derived from a cycloalkane by removal of a hydrogen atom from a ring and has the general formula . Typically an alkyl is a part of a larger molecule. In structural formulae, the symbol R is used to designate a generic (unspecified) alkyl group. The smallest alkyl group is methyl, with the formula .
LigandIn 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 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".
CorrelationIn statistics, correlation or dependence is any statistical relationship, whether causal or not, between two random variables or bivariate data. Although in the broadest sense, "correlation" may indicate any type of association, in statistics it usually refers to the degree to which a pair of variables are linearly related. Familiar examples of dependent phenomena include the correlation between the height of parents and their offspring, and the correlation between the price of a good and the quantity the consumers are willing to purchase, as it is depicted in the so-called demand curve.
Organoruthenium chemistryOrganoruthenium chemistry is the chemistry of organometallic compounds containing a carbon to ruthenium chemical bond. Several organoruthenium catalysts are of commercial interest and organoruthenium compounds have been considered for cancer therapy. The chemistry has some stoichiometric similarities with organoiron chemistry, as iron is directly above ruthenium in group 8 of the periodic table. The most important reagents for the introduction of ruthenium are ruthenium(III) chloride and triruthenium dodecacarbonyl.
AmineIn chemistry, amines (əˈmi:n,_ˈæmi:n, ˈeɪmiːn) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group (these may respectively be called alkylamines and arylamines; amines in which both types of substituent are attached to one nitrogen atom may be called alkylarylamines). Important amines include amino acids, biogenic amines, trimethylamine, and aniline.
Metal carbonylMetal carbonyls are coordination complexes of transition metals with carbon monoxide ligands. Metal carbonyls are useful in organic synthesis and as catalysts or catalyst precursors in homogeneous catalysis, such as hydroformylation and Reppe chemistry. In the Mond process, nickel tetracarbonyl is used to produce pure nickel. In organometallic chemistry, metal carbonyls serve as precursors for the preparation of other organometallic complexes.
CisplatinCisplatin is a chemotherapy medication used to treat a number of cancers. These include testicular cancer, ovarian cancer, cervical cancer, bladder cancer, head and neck cancer, esophageal cancer, lung cancer, mesothelioma, brain tumors and neuroblastoma. It is given by injection into a vein. Common side effects include bone marrow suppression, hearing problems, including total irreversible hearing loss, usually restricted to one ear, kidney damage, and vomiting.
Phenyl groupIn organic chemistry, the phenyl group, or phenyl ring, is a cyclic group of atoms with the formula , and is often represented by the symbol Ph. Phenyl group is closely related to benzene and can be viewed as a benzene ring, minus a hydrogen, which may be replaced by some other element or compound to serve as a functional group. Phenyl group has six carbon atoms bonded together in a hexagonal planar ring, five of which are bonded to individual hydrogen atoms, with the remaining carbon bonded to a substituent.
Intraclass correlationIn statistics, the intraclass correlation, or the intraclass correlation coefficient (ICC), is a descriptive statistic that can be used when quantitative measurements are made on units that are organized into groups. It describes how strongly units in the same group resemble each other. While it is viewed as a type of correlation, unlike most other correlation measures, it operates on data structured as groups rather than data structured as paired observations.
Correlation does not imply causationThe phrase "correlation does not imply causation" refers to the inability to legitimately deduce a cause-and-effect relationship between two events or variables solely on the basis of an observed association or correlation between them. The idea that "correlation implies causation" is an example of a questionable-cause logical fallacy, in which two events occurring together are taken to have established a cause-and-effect relationship. This fallacy is also known by the Latin phrase cum hoc ergo propter hoc ('with this, therefore because of this').
RedoxRedox (ˈrɛdɒks , ˈriːdɒks , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. There are two classes of redox reactions: Electron-transfer – Only one (usually) electron flows from the atom being oxidized to the atom that is reduced. This type of redox reaction is often discussed in terms of redox couples and electrode potentials.
Triruthenium dodecacarbonylTriruthenium dodecacarbonyl is the chemical compound with the formula Ru3(CO)12. Classified as metal carbonyl cluster, it is a dark orange-colored solid that is soluble in nonpolar organic solvents. The compound serves as a precursor to other organoruthenium compounds. The cluster has D3h symmetry, consisting of an equilateral triangle of Ru atoms, each of which bears two axial and two equatorial CO ligands. The Ru-Ru distance is 284 pm. Os3(CO)12 has the same structure. In Fe3(CO)12, two CO ligands are bridging, resulting in C2v symmetry.
CarcinomaCarcinoma is a malignancy that develops from epithelial cells. Specifically, a carcinoma is a cancer that begins in a tissue that lines the inner or outer surfaces of the body, and that arises from cells originating in the endodermal, mesodermal or ectodermal germ layer during embryogenesis. Carcinomas occur when the DNA of a cell is damaged or altered and the cell begins to grow uncontrollably and become malignant. It is from the καρκίνωμα (itself derived from karkinos meaning crab).Oxford English Dictionary, 3rd edition, s.
Vanadium redox batteryThe vanadium redox battery (VRB), also known as the vanadium flow battery (VFB) or vanadium redox flow battery (VRFB), is a type of rechargeable flow battery. It employs vanadium ions as charge carriers. The battery uses vanadium's ability to exist in a solution in four different oxidation states to make a battery with a single electroactive element instead of two. For several reasons, including their relative bulkiness, vanadium batteries are typically used for grid energy storage, i.e.
