The melting point of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium; the melting point of a substance depends on pressure and is specified at a standard pressure such as 1 atmosphere or 100 kPa. When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point or crystallization point; because of the ability of some substances to supercool, the freezing point is not considered as a characteristic property of a substance. When the "characteristic freezing point" of a substance is determined, in fact the actual methodology is always "the principle of observing the disappearance rather than the formation of ice", that is, the melting point. For most substances and freezing points are equal. For example, the melting point and freezing point of mercury is 234.32 kelvins. However, certain substances possess differing solid-liquid transition temperatures.
For example, agar melts at 85 °C and solidifies from 31 °C. The melting point of ice at 1 atmosphere of pressure is close to 0 °C. In the presence of nucleating substances, the freezing point of water is not always the same as the melting point. In the absence of nucleators water can exist as a supercooled liquid down to −48.3 °C before freezing. The chemical element with the highest melting point is tungsten, at 3,414 °C; the often-cited carbon does not melt at ambient pressure but sublimes at about 3,726.85 °C. Tantalum hafnium carbide is a refractory compound with a high melting point of 4215 K. At the other end of the scale, helium does not freeze at all at normal pressure at temperatures arbitrarily close to absolute zero. Many laboratory techniques exist for the determination of melting points. A Kofler bench is a metal strip with a temperature gradient. Any substance can be placed on a section of the strip, revealing its thermal behaviour at the temperature at that point. Differential scanning calorimetry gives information on melting point together with its enthalpy of fusion.
A basic melting point apparatus for the analysis of crystalline solids consists of an oil bath with a transparent window and a simple magnifier. The several grains of a solid are placed in a thin glass tube and immersed in the oil bath; the oil bath is heated and with the aid of the magnifier melting of the individual crystals at a certain temperature can be observed. In large/small devices, the sample is placed in a heating block, optical detection is automated; the measurement can be made continuously with an operating process. For instance, oil refineries measure the freeze point of diesel fuel online, meaning that the sample is taken from the process and measured automatically; this allows for more frequent measurements as the sample does not have to be manually collected and taken to a remote laboratory. For refractory materials the high melting point may be determined by heating the material in a black body furnace and measuring the black-body temperature with an optical pyrometer. For the highest melting materials, this may require extrapolation by several hundred degrees.
The spectral radiance from an incandescent body is known to be a function of its temperature. An optical pyrometer matches the radiance of a body under study to the radiance of a source, calibrated as a function of temperature. In this way, the measurement of the absolute magnitude of the intensity of radiation is unnecessary. However, known temperatures must be used to determine the calibration of the pyrometer. For temperatures above the calibration range of the source, an extrapolation technique must be employed; this extrapolation is accomplished by using Planck's law of radiation. The constants in this equation are not known with sufficient accuracy, causing errors in the extrapolation to become larger at higher temperatures. However, standard techniques have been developed to perform this extrapolation. Consider the case of using gold as the source. In this technique, the current through the filament of the pyrometer is adjusted until the light intensity of the filament matches that of a black-body at the melting point of gold.
This establishes the primary calibration temperature and can be expressed in terms of current through the pyrometer lamp. With the same current setting, the pyrometer is sighted on another black-body at a higher temperature. An absorbing medium of known transmission is inserted between this black-body; the temperature of the black-body is adjusted until a match exists between its intensity and that of the pyrometer filament. The true higher temperature of the black-body is determined from Planck's Law; the absorbing medium is removed and the current through the filament is adjusted to match the filament intensity to that of the black-body. This establishes a second calibration point for the pyrometer; this step is repeated to carry the calibration to hi
Simplified molecular-input line-entry system
The simplified molecular-input line-entry system is a specification in the form of a line notation for describing the structure of chemical species using short ASCII strings. SMILES strings can be imported by most molecule editors for conversion back into two-dimensional drawings or three-dimensional models of the molecules; the original SMILES specification was initiated in the 1980s. It has since been extended. In 2007, an open standard called. Other linear notations include the Wiswesser line notation, ROSDAL, SYBYL Line Notation; the original SMILES specification was initiated by David Weininger at the USEPA Mid-Continent Ecology Division Laboratory in Duluth in the 1980s. Acknowledged for their parts in the early development were "Gilman Veith and Rose Russo and Albert Leo and Corwin Hansch for supporting the work, Arthur Weininger and Jeremy Scofield for assistance in programming the system." The Environmental Protection Agency funded the initial project to develop SMILES. It has since been modified and extended by others, most notably by Daylight Chemical Information Systems.
In 2007, an open standard called "OpenSMILES" was developed by the Blue Obelisk open-source chemistry community. Other'linear' notations include the Wiswesser Line Notation, ROSDAL and SLN. In July 2006, the IUPAC introduced the InChI as a standard for formula representation. SMILES is considered to have the advantage of being more human-readable than InChI; the term SMILES refers to a line notation for encoding molecular structures and specific instances should be called SMILES strings. However, the term SMILES is commonly used to refer to both a single SMILES string and a number of SMILES strings; the terms "canonical" and "isomeric" can lead to some confusion when applied to SMILES. The terms are not mutually exclusive. A number of valid SMILES strings can be written for a molecule. For example, CCO, OCC and CC all specify the structure of ethanol. Algorithms have been developed to generate the same SMILES string for a given molecule; this SMILES is unique for each structure, although dependent on the canonicalization algorithm used to generate it, is termed the canonical SMILES.
These algorithms first convert the SMILES to an internal representation of the molecular structure. Various algorithms for generating canonical SMILES have been developed and include those by Daylight Chemical Information Systems, OpenEye Scientific Software, MEDIT, Chemical Computing Group, MolSoft LLC, the Chemistry Development Kit. A common application of canonical SMILES is indexing and ensuring uniqueness of molecules in a database; the original paper that described the CANGEN algorithm claimed to generate unique SMILES strings for graphs representing molecules, but the algorithm fails for a number of simple cases and cannot be considered a correct method for representing a graph canonically. There is no systematic comparison across commercial software to test if such flaws exist in those packages. SMILES notation allows the specification of configuration at tetrahedral centers, double bond geometry; these are structural features that cannot be specified by connectivity alone and SMILES which encode this information are termed isomeric SMILES.
A notable feature of these rules is. The term isomeric SMILES is applied to SMILES in which isotopes are specified. In terms of a graph-based computational procedure, SMILES is a string obtained by printing the symbol nodes encountered in a depth-first tree traversal of a chemical graph; the chemical graph is first trimmed to remove hydrogen atoms and cycles are broken to turn it into a spanning tree. Where cycles have been broken, numeric suffix labels are included to indicate the connected nodes. Parentheses are used to indicate points of branching on the tree; the resultant SMILES form depends on the choices: of the bonds chosen to break cycles, of the starting atom used for the depth-first traversal, of the order in which branches are listed when encountered. Atoms are represented by the standard abbreviation of the chemical elements, in square brackets, such as for gold. Brackets may be omitted in the common case of atoms which: are in the "organic subset" of B, C, N, O, P, S, F, Cl, Br, or I, have no formal charge, have the number of hydrogens attached implied by the SMILES valence model, are the normal isotopes, are not chiral centers.
All other elements must be enclosed in brackets, have charges and hydrogens shown explicitly. For instance, the SMILES for water may be written as either O or. Hydrogen may be written as a separate atom; when brackets are used, the symbol H is added if the atom in brackets is bonded to one or more hydrogen, followed by the number of hydrogen atoms if greater than 1 by the sign + for a positive charge or by - for a negative charge. For example, for ammonium. If there is more than one charge, it is written as digit.
European Chemicals Agency
The European Chemicals Agency is an agency of the European Union which manages the technical and administrative aspects of the implementation of the European Union regulation called Registration, Evaluation and Restriction of Chemicals. ECHA is the driving force among regulatory authorities in implementing the EU's chemicals legislation. ECHA helps companies to comply with the legislation, advances the safe use of chemicals, provides information on chemicals and addresses chemicals of concern, it is located in Finland. The agency headed by Executive Director Bjorn Hansen, started working on 1 June 2007; the REACH Regulation requires companies to provide information on the hazards and safe use of chemical substances that they manufacture or import. Companies register this information with ECHA and it is freely available on their website. So far, thousands of the most hazardous and the most used substances have been registered; the information is technical but gives detail on the impact of each chemical on people and the environment.
This gives European consumers the right to ask retailers whether the goods they buy contain dangerous substances. The Classification and Packaging Regulation introduces a globally harmonised system for classifying and labelling chemicals into the EU; this worldwide system makes it easier for workers and consumers to know the effects of chemicals and how to use products safely because the labels on products are now the same throughout the world. Companies need to notify ECHA of the labelling of their chemicals. So far, ECHA has received over 5 million notifications for more than 100 000 substances; the information is available on their website. Consumers can check chemicals in the products. Biocidal products include, for example, insect disinfectants used in hospitals; the Biocidal Products Regulation ensures that there is enough information about these products so that consumers can use them safely. ECHA is responsible for implementing the regulation; the law on Prior Informed Consent sets guidelines for the import of hazardous chemicals.
Through this mechanism, countries due to receive hazardous chemicals are informed in advance and have the possibility of rejecting their import. Substances that may have serious effects on human health and the environment are identified as Substances of Very High Concern 1; these are substances which cause cancer, mutation or are toxic to reproduction as well as substances which persist in the body or the environment and do not break down. Other substances considered. Companies manufacturing or importing articles containing these substances in a concentration above 0,1% weight of the article, have legal obligations, they are required to inform users about the presence of the substance and therefore how to use it safely. Consumers have the right to ask the retailer whether these substances are present in the products they buy. Once a substance has been identified in the EU as being of high concern, it will be added to a list; this list is available on ECHA's website and shows consumers and industry which chemicals are identified as SVHCs.
Substances placed on the Candidate List can move to another list. This means that, after a given date, companies will not be allowed to place the substance on the market or to use it, unless they have been given prior authorisation to do so by ECHA. One of the main aims of this listing process is to phase out SVHCs where possible. In its 2018 substance evaluation progress report, ECHA said chemical companies failed to provide “important safety information” in nearly three quarters of cases checked that year. "The numbers show a similar picture to previous years" the report said. The agency noted that member states need to develop risk management measures to control unsafe commercial use of chemicals in 71% of the substances checked. Executive Director Bjorn Hansen called non-compliance with REACH a "worry". Industry group CEFIC acknowledged the problem; the European Environmental Bureau called for faster enforcement to minimise chemical exposure. European Chemicals Bureau Official website
An alcoholic drink is a drink that contains ethanol, a type of alcohol produced by fermentation of grains, fruits, or other sources of sugar. Drinking alcohol plays an important social role in many cultures. Most countries have laws regulating the production and consumption of alcoholic beverages; some countries ban such activities but alcoholic drinks are legal in most parts of the world. The global alcoholic drink industry exceeded $1 trillion in 2014. Alcohol is a depressant, which in low doses causes euphoria, reduces anxiety, improves sociability. In higher doses, it causes drunkenness, unconsciousness, or death. Long-term use can lead to alcohol abuse, physical dependence, alcoholism. Alcohol is one of the most used recreational drugs in the world with about 33% of people being current drinkers; as of 2016 women on average drink 0.7 drinks and males 1.7 drinks a day. In 2015, among Americans, 86% of adults had consumed alcohol at some point, 70% had drunk it in the last year, 56% in the last month.
Alcoholic drinks are divided into three classes—beers and spirits—and their alcohol content is between 3% and 50%. Discovery of late Stone Age jugs suggest that intentionally fermented drinks existed at least as early as the Neolithic period. Many animals consume alcohol when given the opportunity and are affected in much the same way as humans, although humans are the only species known to produce alcoholic drinks intentionally. Beer is a beverage fermented from grain mash, it is made from barley or a blend of several grains and flavored with hops. Most beer is carbonated as part of the fermentation process. If the fermented mash is distilled the drink becomes a spirit. In the Andean region, the most common beer is chicha, made from grain or fruits. Beer is the most consumed alcoholic beverage in the world. Cider or cyder is a fermented alcoholic drink made from any fruit juice. Cider alcohol content varies from 1.2% ABV to 8.5% or more in traditional English ciders. In some regions, cider may be called "apple wine".
Mead is an alcoholic drink made by fermenting honey with water, sometimes with various fruits, grains, or hops. The alcoholic content of mead may range from about 8% ABV to more than 20%; the defining characteristic of mead is that the majority of the drink's fermentable sugar is derived from honey. Pulque is the Mesoamerican fermented drink made from the "honey water" of maguey cacti; the drink distilled from pulque is mescal. Wine is a fermented beverage produced from sometimes other fruits. Wine involves a longer fermentation process than beer and a long aging process, resulting in an alcohol content of 9%–16% ABV. "Fruit wines" are made from fruits other than grapes, such as cherries, or apples. Sake is a popular example of "rice wine". Sparkling wine like French Champagne, Catalan Cava or Italian Prosecco can be made by means of a secondary fermentation. A distilled drink or liquor is an alcoholic drink produced by distilling ethanol produced by means of fermenting grain, fruit, or vegetables.
Unsweetened, alcoholic drinks that have an alcohol content of at least 20% ABV are called spirits. For the most common distilled drinks, such as whiskey and vodka, the alcohol content is around 40%; the term hard liquor is used in North America to distinguish distilled drinks from undistilled ones. Vodka, baijiu, whiskey and soju are examples of distilled drinks. Distilling eliminates some of the congeners. Freeze distillation concentrates ethanol along with fusel alcohols in applejack. Fortified wine is wine, such as sherry, to which a distilled beverage has been added. Fortified wine is distinguished from spirits made from wine in that spirits are produced by means of distillation, while fortified wine is wine that has had a spirit added to it. Many different styles of fortified wine have been developed, including port, madeira, marsala and the aromatized wine vermouth. Rectified spirit called "neutral grain spirit", is alcohol, purified by means of "rectification"; the term neutral refers to the spirit's lack of the flavor that would have been present if the mash ingredients had been distilled to a lower level of alcoholic purity.
Rectified spirit lacks any flavoring added to it after distillation. Other kinds of spirits, such as whiskey, are distilled to a lower alcohol percentage to preserve the flavor of the mash. Rectified spirit is a clear, flammable liquid that may contain as much as 95% ABV, it is used for medicinal purposes. It may be a grain spirit or it may be made from other plants, it is used in mixed drinks and tinctures, as a household solvent. Alcohol has significant negative health effects, including increased risk of cancer. Negative effects are related to the amount consumed with no safe lower limit seen. Wine, distilled spirits and other alcoholic drinks contain ethyl alcohol and alcohol consumption has short-term psychological and physiological effects on the user. Different concentrations of alcohol in the human body have different effects on a person; the effects of alcohol depend on the amount an individual has drunk, the percentage of alcohol in the wine, beer or spirits and the timespan that the consumption took place, the amount of food eaten and whether an indiv
Amobarbital is a drug, a barbiturate derivative. It has sedative-hypnotic properties, it is a white crystalline powder with no odor and a bitter taste. It was first synthesized in Germany in 1923, it is considered an intermediate acting barbiturate. If amobarbital is taken for extended periods of time and psychological dependence can develop. Amobarbital withdrawal may be life-threatening. Amobarbital was once manufactured by Eli Lilly and Company in the US under the brand name Amytal in bright blue bullet shaped capsule form containing either 50 or 100 mg of the drug, it was abused, known as "blue heavens" on the streets, was discontinued by Eli Lilly in the early 1980s. In an in vitro study in fat thalamic slices amobarbital worked by activating GABAA receptors, which decreased input resistance, depressed burst and tonic firing in ventrobasal and intralaminar neurons, while at the same time increasing burst duration and mean conductance at individual chloride channels. Amobarbital has been used in a study to inhibit mitochondrial electron transport in the rat heart in an attempt to preserve mitochondrial function following reperfusion.
A 1988 study found that amobarbital increases benzodiazepine receptor binding in vivo with less potency than secobarbital and pentobarbital, but greater than phenobarbital and barbital. It has an LD50 in mice of 212 mg/kg s.c. Amobarbital undergoes both hydroxylation to form 3'-hydroxyamobarbital, N-glucosidation to form 1-amobarbital. Anxiety Epilepsy Insomnia Wada test When given by an intravenous route, sodium amobarbital has a reputation for acting as a so-called truth serum. Under the influence, a person will divulge information that under normal circumstances they would block; this was most due to loss of inhibition. As such, the drug was first employed clinically by Dr. William Bleckwenn at the University of Wisconsin to circumvent inhibitions in psychiatric patients; the use of amobarbital as a truth serum has lost credibility due to the discovery that a subject can be coerced into having a "false memory" of the event. The drug may be used intravenously to interview patients with catatonic mutism, sometimes combined with caffeine to prevent sleep.
It was used by the United States armed forces during World War II in an attempt to treat shell shock and return soldiers to the front-line duties. This use has since been discontinued as the powerful sedation, cognitive impairment, dis-coordination induced by the drug reduced soldiers' usefulness in the field. Amobarbital was once manufactured in the US by Eli Lilly Pharmaceuticals under the brand name Amytal in capsule form, it was discontinued in the early 80's replaced by the benzodiazepine family of drugs. Amobarbital was widely abused, known on the streets as "blue heavens" because of their blue capsule; the following drugs should be avoided when taking amobarbital: Antiarrhythmics, such as verapamil and digoxin Antiepileptics, such as phenobarbital or carbamazepine Antihistamines, such as doxylamine and clemastine Antihypertensives, such as atenolol and propranolol EthanolAlcohol https://www.drugs.com/food-interactions/amobarbital.html Benzodiazepines, such as diazepam, nitrazepam,alprazolam,or lorazepam Chloramphenicol Chlorpromazine Cyclophosphamide Ciclosporin Digitoxin Doxorubicin Doxycycline Methoxyflurane Metronidazole Narcotic analgesics, such as morphine and oxycodone Quinine Steroids, such as prednisone and cortisone Theophylline Warfarin Amobarbital has been known to decrease the effects of hormonal birth control, sometimes to the point of uselessness.
Being chemically related to phenobarbital, it might do the same thing to digitoxin, a cardiac glycoside. Some side effects of overdose include confusion. Amobarbital, like all barbiturates, is synthesized by reacting malonic acid derivatives with urea derivatives. In particular, in order to make amobarbital, α-ethyl-α-isoamylmalonic ester is reacted with urea, it has been used to convict alleged murderers such as Andres English-Howard, who strangled his girlfriend to death but claimed innocence. He was surreptitiously administered the drug by his lawyer, under the influence of it he revealed why he strangled her and under what circumstances. On the night of August 28, 1951, the housekeeper of actor Robert Walker found him to be in an emotional state, she called Walker's psychiatrist who administered amobarbital for sedation. Walker was drinking prior to his emotional outburst, it is believed the combination of amobarbital and alcohol resulted in a severe reaction; as a result, he passed out and stopped breathing, all efforts to resuscitate him failed.
Walker died at 32 years old. Eli Lilly manufactured Amobarbital under the brand name Amytal, it was discontinued in the 1980's replaced by the benzodiazepine family of drugs. Amytal was widely abused. Street names for Amobarbital include "blues", "blue angels", "blue birds", "blue devils", "blue heavens" due to their blue capsule. Blue 88 Depressant Tuinal
Valerian is a perennial flowering plant native to Europe and Asia. In the summer when the mature plant may have a height of 1.5 metres, it bears sweetly scented pink or white flowers that attract many fly species hoverflies of the genus Eristalis. It is consumed as food including the grey pug. Crude extract of valerian root may have sedative and anxiolytic effects, is sold in dietary supplement capsules to promote sleep. Valerian has been used as a medicinal herb since at least the time of ancient Rome. Hippocrates described its properties, Galen prescribed it as a remedy for insomnia. In medieval Sweden, it was sometimes placed in the wedding clothes of the groom to ward off the "envy" of the elves. In the 16th century, the Anabaptist reformer Pilgram Marpeck prescribed valerian tea for a sick woman. John Gerard's Herball states that his contemporaries found Valerian "excellent for those burdened and for such as be troubled with croup and other like convulsions, for those that are bruised with falls."
He says that the dried root was valued as a medicine by the poor in the north of England and the south of Scotland, so that "no broth or pottage or physicall meats be worth anything if Setewale be not there."The seventeenth century astrological botanist Nicholas Culpeper thought the plant was "under the influence of Mercury, therefore hath a warming faculty." He recommended both herb and root, said that "the root boiled with liquorice and aniseed is good for those troubled with cough. It is of special value against the plague, the decoction thereof being drunk and the root smelled; the green herb being bruised and applied to the head taketh away pain and pricking thereof." The name of the herb is derived from the Latin verb valere. Other names used for this plant include garden valerian, garden heliotrope and all-heal. Red valerian grown in gardens, is sometimes referred to as "valerian", but is a different species, from the same family but not closely related. Known compounds detected in valerian that may contribute to its method of action are: Alkaloids: actinidine, shyanthine and valerine Isovaleramide may be created in the extraction process.
Gamma-aminobutyric acid Isovaleric acid Iridoids, including valepotriates: isovaltrate and valtrate Sesquiterpenes: valerenic acid, hydroxyvalerenic acid and acetoxyvalerenic acid Flavanones: hesperidin, 6-methylapigenin, linarin Because of valerian's historical use as a sedative, anticonvulsant, migraine treatment, pain reliever, most basic science research has been directed at the interaction of valerian constituents with the GABA receptor. Many studies remain all require clinical validation; the mechanism of action of valerian in general, as a mild sedative in particular, has not been elucidated. However, some of the GABA-analogs valerenic acids as components of the essential oil along with other semivolatile sesquiterpenoids are believed to have some affinity for the GABAA receptor, a class of receptors on which benzodiazepines are known to act. Valeric acid, responsible for the typical odor of older valerian roots, does not have any sedative properties. Valeric acid is related to valproic acid, a prescribed anticonvulsant.
Valerian contains isovaltrate, shown to be an inverse agonist for adenosine A1 receptor sites. This action does not contribute to the herb's possible sedative effects, which would be expected from an agonist, rather than an inverse agonist, at this particular binding site. Hydrophilic extractions of the herb sold over the counter, however do not contain significant amounts of isovaltrate. Valerenic acid in valerian stimulates serotonin receptors as a partial agonist, including 5-HT5A, implicated in the sleep-wake cycle; the chief constituent of valerian is a yellowish-green to brownish-yellow oil present in the dried root, varying in content from 0.5 to 2.0%. This variation in quantity may be determined by location; the volatile oils that form the active ingredient are pungent, somewhat reminiscent of well-matured cheese. Though some people remain partial to the earthy scent, some find it unpleasant, comparing the odor to that of unwashed feet. Although valerian is a common traditional medicine used for treating insomnia, there is no good evidence it is effective for this purpose.
Valerian is not helpful in treating anxiety. There is insufficient evidence for safety of valerian for anxiety disorders; the European Medicines Agency approved the health claim that valerian can be used as a traditional herbal medicine to relieve mild nervous tension and to aid sleep. In the United States, valerian extracts are sold as a nutritional supplement under the Dietary Supplement Health and Education Act of 1994. Oral forms are available in both unstandardized forms. Standardized products may be preferable considering the wide variation of the chemicals in the dried root, as noted above; when standardized, it is done so as a percentage of valeric acid. Because th
Tert-Butyl alcohol called tert-butanol or t-butanol, is the simplest tertiary alcohol, with a formula of 3COH. It is one of the four isomers of butanol. Tert-Butyl alcohol is a colorless solid, which melts near room temperature and has a camphor-like odor, it is miscible with water and diethyl ether. Tert-Butyl alcohol has been identified in beer and chickpeas, it is found in cassava, used as a fermentation ingredient in certain alcoholic beverages. Tert-Butyl alcohol is derived commercially from isobutane as a coproduct of propylene oxide production, it can be produced by the catalytic hydration of isobutylene, or by a Grignard reaction between acetone and methylmagnesium chloride. Purification cannot be performed by simple distillation due to formation of an azeotrope with water, although initial drying of the solvent containing large amounts of water is performed by adding benzene to form a tertiary azeotrope and distilling off the water. Smaller amounts of water are removed by drying with calcium oxide, potassium carbonate, calcium sulfate, or magnesium sulfate, followed by fractional distillation.
Anhydrous tert-butyl alcohol is obtained by further refluxing and distilling from magnesium activated with iodine, or alkali metals such as sodium or potassium. Other methods include the use of 4 Å molecular sieves, aluminium tert-butylate, calcium hydride, or fractional crystallization under inert atmosphere. Tert-Butyl alcohol is used as a solvent, ethanol denaturant, paint remover ingredient, gasoline octane booster and oxygenate, it is a chemical intermediate used to produce methyl tert-butyl ether and ethyl tert-butyl ether by reaction with methanol and ethanol and tert-butyl hydroperoxide by reaction with hydrogen peroxide. As a tertiary alcohol, tert-butyl alcohol is more resistant to oxidation and less reactive than the other isomers of butanol; when tert-butyl alcohol is deprotonated with a strong base, the product is an alkoxide anion. In this case, it is tert-butoxide. For example, the used organic reagent potassium tert-butoxide is prepared by refluxing dry tert-butanol with potassium metal.
K + t-BuOH → t-BuO−K+ + 1/2 H2The tert-butoxide is a strong, non-nucleophilic base in organic chemistry. It abstracts acidic protons from substrates, but its steric bulk inhibits the group from participating in nucleophilic substitution, such as in a Williamson ether synthesis or an SN2 reaction. Tert-Butyl alcohol reacts with hydrogen chloride to form tert-butyl chloride, it reacts with sodium in liquid ammonia. There is limited data on the pharmacology and toxicology of tert-butanol in humans and other animals. Human exposure may occur due to fuel oxygenate metabolism. Tert-butanol is poorly absorbed through skin but absorbed if inhaled or ingested. Tert-butanol is irritating to skin or eyes. Toxicity of single doses is low but high doses can produce a sedative or anesthetic effect. International Chemical Safety Card 0114 NIOSH Pocket Guide to Chemical Hazards. "#0078". National Institute for Occupational Safety and Health. IPCS Environmental Health Criteria 65: Butanols: four isomers IPCS Health and Safety Guide 7: tert-Butanol