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Cadet's Fuming Liquid
Cadet's fuming liquid was a red-brown oily liquid prepared in 1760 by the French chemist Louis Claude Cadet de Gassicourt (1731-1799) by the reaction of potassium acetate with arsenic trioxide. It consisted mostly of dicacodyl (((CH3)2As)2) and cacodyl oxide (((CH3)2As)2O). The global reaction (mass balance) corresponding to the oxide formation is the following: : These were the first organometallic substances prepared; as such, Cadet has been regarded as the father of organometallic chemistry. This liquid develops white fumes when exposed to air, resulting in a pale flame producing carbon dioxide, water, and arsenic trioxide. It has a nauseating and very disagreeable garlic-like odor. Around 1840, Robert Bunsen did much work on characterizing the compounds in the liquid and its derivatives. His research was important in the development of radical theory Radical theory is an obsolete scientific theory in chemistry describing the structure of organic compounds. The theory wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Louis Claude Cadet De Gassicourt
Louis Claude Cadet de Gassicourt (24 July 1731 – 17 October 1799) was a French chemist who synthesised the first organometalic compound. He obtained a red liquid by the reaction of potassium acetate with arsenic trioxide. This liquid is known as Cadet's fuming liquid and contains the two compounds cacodyl and cacodyl oxide. Cadet studied at the Collège des Quatre-Nations and became a pharmacist at the Hotel Royal des Invalides in Paris. He was the brother of the pharmacist Antoine-Alexis Cadet de Vaux. Marie Thérèse Françoise Boisselet became his wife in 1771, at that time her son, fathered by Louis XV, was two years old. The boy was adopted by Cadet as Charles-Louis Cadet. Cadet was elected to the American Philosophical Society in 1787. In 1825, botanist Antoine Laurent Apollinaire Fée circumscribed ''Gassicurtia'' which is a genus of lichenized fungi in the family Caliciaceae The Caliciaceae are a family of mostly lichen-forming fungi belonging to the class ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Acetate
Potassium acetate (CH3COOK) is the potassium salt of acetic acid. It is a hygroscopic solid at room temperature. Preparation It can be prepared by treating a potassium-containing base such as potassium hydroxide or potassium carbonate with acetic acid: :CH3COOH + KOH → CH3COOK + H2O This sort of reaction is known as an acid-base neutralization reaction. The sesquihydrate in water solution (CH3COOK·1½H2O) begins to form semihydrate at 41.3 °C. Applications Deicing Potassium acetate (as a substitute for calcium chloride or magnesium chloride) can be used as a deicer to remove ice or prevent its formation. It offers the advantage of being less aggressive on soils and much less corrosive: for this reason, it is preferred for airport runways although it is more expensive. Fire extinguishing Potassium acetate is the extinguishing agent used in Class K fire extinguishers because of its ability to cool and form a crust over burning oils. Food additive Potassium acetate is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsenic Trioxide
Arsenic trioxide, sold under the brand name Trisenox among others, is an inorganic compound and medication. As an industrial chemical, whose major uses include in the manufacture of wood preservatives, pesticides, and glass. As a medication, it is used to treat a type of cancer known as acute promyelocytic leukemia. For this use it is given by injection into a vein. Common side effects include vomiting, diarrhea, swelling, shortness of breath, and headaches. Severe side effects may include APL differentiation syndrome and heart problems. Use during pregnancy or breastfeeding may harm the baby. Arsenic trioxide has the formula . Its mechanism in treating cancer is not entirely clear. Arsenic trioxide was approved for medical use in the United States in 2000. It is on the World Health Organization's List of Essential Medicines. Approximately 50,000 tonnes are produced a year. Due to its toxicity, a number of countries have regulations around its manufacture and sale. Uses M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dicacodyl
Cacodyl, also known as dicacodyl or tetramethyldiarsine, (CH3)2As–As(CH3)2, is an organoarsenic compound that constitutes a major part of "Cadet's fuming liquid" (named after the French chemist Louis Claude Cadet de Gassicourt). It is a poisonous oily liquid with an extremely unpleasant garlicky odor. Cacodyl undergoes spontaneous combustion in dry air. Cacodyl is also the name of the functional group or radical (CH3)2As. Preparation A mixture of dicacodyl and cacodyl oxide ((CH3)2As–O–As(CH3)2) was first prepared by Cadet by the reaction of potassium acetate with arsenic trioxide. A subsequent reduction yields a mixture of several methylated arsenic compounds including dicacodyl. The global reaction (mass balance) corresponding to the oxide formation is the following: : A more efficient synthesis was later developed which started from the dimethyl arsine chloride and dimethyl arsine: : History Robert Wilhelm Bunsen coined the name kakodyl (later modified to cacodyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cacodyl Oxide
Cacodyl oxide is a chemical compound of the formula CH3)2Assub>2O. This organoarsenic compound is primarily of historical significance since it is sometimes considered to be the first organometallic compound synthesized in relatively pure form. "Cadet's fuming liquid", which is composed of cacodyl and cacodyl oxide, was originally synthesized by heating potassium acetate with arsenic trioxide. It has a disagreeable odor and is toxic. The molecular structure of h2Assub>2O (Ph = phenyl), the tetraphenyl analogue of cacodyl oxide, has been established by X-ray crystallography. See also * Arsenic * Arsine * Cacodylic acid * Lewisite * Cacodyl cyanide Cacodyl cyanide is a highly poisonous organoarsenic compound discovered by Robert Bunsen in the 1840s. It is very volatile and flammable, as it shares the chemical properties of both arsenic and cyanide. Synthesis Cacodyl cyanide can be prepared ... References Cacodyl compounds Foul-smelling chemicals {{organic-compo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organometallic Chemistry
Organometallic chemistry is the study of organometallic compounds, chemical compounds containing at least one chemical bond between a carbon atom of an organic molecule and a metal, including alkali, alkaline earth, and transition metals, and sometimes broadened to include metalloids like boron, silicon, and selenium, as well. Aside from bonds to organyl fragments or molecules, bonds to 'inorganic' carbon, like carbon monoxide (metal carbonyls), cyanide, or carbide, are generally considered to be organometallic as well. Some related compounds such as transition metal hydrides and metal phosphine complexes are often included in discussions of organometallic compounds, though strictly speaking, they are not necessarily organometallic. The related but distinct term " metalorganic compound" refers to metal-containing compounds lacking direct metal-carbon bonds but which contain organic ligands. Metal β-diketonates, alkoxides, dialkylamides, and metal phosphine complexes are repres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Bunsen
Robert Wilhelm Eberhard Bunsen (; 30 March 1811 – 16 August 1899) was a German chemist. He investigated emission spectra of heated elements, and discovered caesium (in 1860) and rubidium (in 1861) with the physicist Gustav Kirchhoff. The Bunsen–Kirchhoff Award for spectroscopy is named after Bunsen and Kirchhoff. Bunsen also developed several gas-analytical methods, was a pioneer in photochemistry, and did early work in the field of organic arsenic chemistry. With his laboratory assistant Peter Desaga, he developed the Bunsen burner, an improvement on the laboratory burners then in use. Early life and education Bunsen was born in Göttingen, Germany in 1811, in what is now the state of Lower Saxony in Germany. Bunsen was the youngest of four sons of the University of Göttingen's chief librarian and professor of modern philology, Christian Bunsen (1770–1837). After attending school in Holzminden, Bunsen matriculated at Göttingen in 1828 and studied chemistry with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radical Theory
Radical theory is an obsolete scientific theory in chemistry describing the structure of organic compounds. The theory was pioneered by Justus von Liebig, Friedrich Wöhler and Auguste Laurent around 1830 and is not related to the modern understanding of free radicals. In this theory, organic compounds were thought to exist as combinations of radicals that could be exchanged in chemical reactions just as chemical elements could be interchanged in inorganic compounds. Preamble The term radical was already in use when radical theory was developed. Louis-Bernard Guyton de Morveau introduced the phrase "radical" in 1785 and the phrase was employed by Antoine Lavoisier in 1789 in his Traité Élémentaire de Chimie. A radical was identified as the root base of certain acids (The Latin word "radix" meaning "root"). The combination of a radical with oxygen would result in an acid. For example the radical of acetic acid was called "acetic" and that of muriatic acid (hydrochloric acid) was c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organoarsenic Compounds
Organoarsenic chemistry is the chemistry of compounds containing a chemical bond between arsenic and carbon. A few organoarsenic compounds, also called "organoarsenicals," are produced industrially with uses as insecticides, herbicides, and fungicides. In general these applications are declining in step with growing concerns about their impact on the environment and human health. The parent compounds are arsane and arsenic acid. Despite their toxicity, organoarsenic biomolecules are well known. History 140px, Cacodyl (tetramethyldiarsine) was one of the first organoarsenic compounds. Surprising for an area now considered of minor importance, organoarsenic chemistry played a prominent role in the history of the field of chemistry. The oldest known organoarsenic compound, the foul smelling cacodyl was reported in "cacodyl" (1760) and is sometimes classified as the first synthetic organometallic compound. The compound Salvarsan was one of the first pharmaceuticals, earning a Nobe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
