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Tetramethylazodicarboxamide
Tetramethylazodicarboxamide (also known as TMAD and diamide) is a reagent used in biochemistry for Organic redox reaction, oxidation of thiols in proteins to Disulfide bond, disulfides. It has also been used as a reagent in the Mitsunobu reaction in place of diethyl azodicarboxylate. References Further reading * Azo compounds Reagents for organic chemistry {{organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Redox Reaction
Organic reductions or organic oxidations or organic redox reactions are redox reactions that take place with organic compounds. In organic chemistry oxidations and reductions are different from ordinary redox reactions, because many reactions carry the name but do not actually involve electron transfer.March Jerry; (1985). Advanced Organic Chemistry reactions, mechanisms and structure (3rd ed.). New York: John Wiley & Sons, inc. Instead the relevant criterion for organic oxidation is gain of oxygen and/or loss of hydrogen, respectively.''Organic Redox Systems: Synthesis, Properties, and Applications'', Tohru Nishinaga 2016 Simple functional groups can be arranged in order of increasing oxidation state. The oxidation numbers are only an approximation: When methane is oxidized to carbon dioxide its oxidation number changes from −4 to +4. Classical reductions include alkene reduction to alkanes and classical oxidations include oxidation of alcohols to aldehydes. In oxidations ... [...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 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. 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 group () bonds very strong ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disulfide Bond
In biochemistry, a disulfide (or disulphide in British English) refers to a functional group with the structure . The linkage is also called an SS-bond or sometimes a disulfide bridge and is usually derived by the coupling of two thiol groups. In biology, disulfide bridges formed between thiol groups in two cysteine residues are an important component of the secondary and tertiary structure of proteins. ''Persulfide'' usually refers to compounds. In inorganic chemistry disulfide usually refers to the corresponding anion (−S−S−). Organic disulfides Symmetrical disulfides are compounds of the formula . Most disulfides encountered in organo sulfur chemistry are symmetrical disulfides. Unsymmetrical disulfides (also called heterodisulfides) are compounds of the formula . They are less common in organic chemistry, but most disulfides in nature are unsymmetrical. Properties The disulfide bonds are strong, with a typical bond dissociation energy of 60 kcal/mol (251& ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitsunobu Reaction
The Mitsunobu reaction is an organic reaction that converts an alcohol into a variety of functional groups, such as an ester, using triphenylphosphine and an azodicarboxylate such as diethyl azodicarboxylate (DEAD) or diisopropyl azodicarboxylate (DIAD). Although DEAD and DIAD are most commonly used, there are a variety of other azodicarboxylates available which facilitate an easier workup and/or purification and in some cases, facilitate the use of more basic nucleophiles. It was discovered by Oyo Mitsunobu (1934–2003). Typical protocol is to add the phosphine and azodicarboxylate together at −10 °C, typically in THF or toluene, until a white precipitate forms. This white, cloudy suspension is the ylide. Then a solution of the nucleophile and alcohol are added together and the reaction can be, and in many cases is, heated to reflux. The alcohol reacts with the phosphine to create a good leaving group then undergoes an inversion of stereochemistry in classic SN2 fashion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethyl Azodicarboxylate
Diethyl azodicarboxylate, conventionally abbreviated as DEAD and sometimes as DEADCAT, is an organic compound with the structural formula CH3CH2O2CN=NCO2CH2CH3. Its molecular structure consists of a central azo functional group, RN=NR, flanked by two ethyl ester groups. This orange-red liquid is a valuable reagent but also quite dangerous and explodes upon heating. Therefore, commercial shipment of pure diethyl azodicarboxylate is prohibited in the United States and is carried out either in solution or on polystyrene particles. DEAD is an aza- dienophile and an efficient dehydrogenating agent, converting alcohols to aldehydes, thiols to disulfides and hydrazo groups to azo groups; it is also a good electron acceptor. While DEAD is used in numerous chemical reactions it is mostly known as a key component of the Mitsunobu reaction, a common strategy for the preparation of an amine, azide, ether, thioether, or ester from the corresponding alcohol. It is used in the synthesis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azo Compounds
Azo compounds are organic compounds bearing the functional group diazenyl (, in which R and R′ can be either aryl or alkyl groups). IUPAC defines azo compounds as: "Derivatives of diazene (diimide), , wherein both hydrogens are substituted by hydrocarbyl groups, e.g. azobenzene or diphenyldiazene." The more stable derivatives contain two aryl groups. The group is called an ''azo group'' (, ). Many textile and leather articles are dyed with azo dyes and pigments. Aryl azo compounds Aryl azo compounds are usually stable, crystalline species. Azobenzene is the prototypical aromatic azo compound. It exists mainly as the ''trans'' isomer, but upon illumination, converts to the ''cis'' isomer. Aromatic azo compounds can be synthesized by azo coupling, which entails an electrophilic substitution reaction where an aryl diazonium cation is attacked by another aryl ring, especially those substituted with electron-donating groups: :ArN2+ + Ar'H -> ArN=NAr' + H+ Since diazoniu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
