121-44-8 Usage
Chemical Description
Different sources of media describe the Chemical Description of 121-44-8 differently. You can refer to the following data:
1. Triethylamine is a colorless liquid used as a base.
2. Triethylamine is a colorless liquid with a strong ammonia-like odor and a molecular formula of C6H15N.
3. Triethylamine is a common organic base used in organic synthesis.
4. Triethylamine is a colorless, volatile liquid with a strong fishy odor and is used as a base in organic synthesis.
5. Triethylamine is a common organic base used in chemical reactions.
6. Triethylamine is a base that is used in organic reactions.
7. Triethylamine is a colorless liquid with a strong, fishy odor.
8. Triethylamine is a commonly used organic base.
9. Triethylamine is a colorless liquid with a strong ammonia-like odor, 4-(4-phenylpiperazin-1-yl)butan-1-amine is a white to off-white powder, imidazo[1,2-a]pyridine-2-carboxylic acid is a white to off-white powder, BOP-Cl is a white to off-white powder, and N-(4-(4-Phenylpiperazin-1-yl)butyl)imidazo[1,2-a]pyridine-2-carboxamide is a colorless solid.
10. Triethylamine is a tertiary amine used as a base in organic chemistry.
11. Triethylamine is a tertiary amine with the formula N(CH2CH3)3, which is commonly used as a base in organic chemistry.
12. Triethylamine is a colorless liquid with a strong, ammonia-like odor.
13. Triethylamine is a tertiary amine, and 1,7-dihydroxycarbonyl-1,7-dicarba-closo-dodecaborane is a boron-containing ligand.
14. Triethylamine is a tertiary amine with the chemical formula (C2H5)3N.
15. Triethylamine is a colorless liquid used as a solvent and in the production of pharmaceuticals and other chemicals.
16. Triethylamine is a colorless liquid used as a base in organic synthesis.
17. Triethylamine is a colorless, volatile liquid with the formula N(CH2CH3)3.
18. Triethylamine is used as a base to deprotonate the phosphaamidinate ligands.
19. Triethylamine is a tertiary amine used as a base in organic synthesis.
20. Triethylamine is a tertiary amine with the formula N(CH2CH3)3, commonly used as a base in organic chemistry.
21. Triethylamine is a common organic base that can be used to catalyze reactions.
22. Triethylamine, diisopropylethylamine, DBU, and pyridine are organic bases that show the same reactivity as K2CO3.
23. Triethylamine is used as a catalyst.
24. Triethylamine is a common base used in organic chemistry.
25. Triethylamine is a tertiary amine that is commonly used as a base in organic chemistry.
26. Triethylamine is a tertiary amine that is used as a base in organic reactions.
27. Triethylamine is a base that is used to catalyze the reaction between the amino acid and the glucose derivative.
28. Triethylamine is a tertiary amine that is commonly used as a base in organic synthesis.
29. Triethylamine is a colorless, strongly alkaline liquid used as a base in organic synthesis.
30. Triethylamine is a base used as a catalyst in the reaction.
31. Triethylamine is a colorless liquid with a strong ammonia-like odor, commonly used as a base in organic synthesis.
32. Triethylamine is a base used as a catalyst, THF is a solvent, AIBN is a radical initiator, and methacrylic chloride is a monomer used to form the polymer.
33. Triethylamine is a base used in organic synthesis.
Outline
Triethylamine (formula: C6H15N), also known as N, N-diethylethanamine, is the most simple tri-substituted uniformly tertiary amine, having typical properties of tertiary amines, including salifying, oxidation, Hing Myers test (Hisberg reaction) for triethylamine does not respond. It is colorless to pale yellow transparent liquid, with a strong smell of ammonia, slightly fuming in the air. Boiling point: 89.5 ℃, relative density (water = 1): 0.70, the relative density (Air = 1): 3.48, slightly soluble in water, soluble in alcohol, ether. Aqueous solution is alkaline, flammable. Vapor and air can form explosive mixtures, the explosion limit is 1.2% to 8.0%. It is toxic, with a strong irritant.
Uses
Different sources of media describe the Uses of 121-44-8 differently. You can refer to the following data:
1. Triethylamine is a clear, colorless liquid with an Ammonia or fish-like odor. It is used in making waterproofing agents, and as a catalyst, corrosion inhibitor and propellant.
It is mainly used as base, catalyst, solvent and raw material in organic synthesis and is generally abbreviated as Et3N, NEt3 or TEA. It can be used to prepare phosgene polycarbonate catalyst, polymerization inhibitor of tetrafluoroethylene, rubber vulcanization accelerator, special solvent in paint remover, enamel anti-hardener, surfactant, antiseptic, wetting agent, bactericides, ion exchange resins, dyes, fragrances, pharmaceuticals, high-energy fuels, and liquid rocket propellants, as a curing and hardening agent for polymers and for the desalination of seawater.
Consumption Quota of in medical industry:
▼▲
Medicine
Consumption Quota(Unit: t/t)
Ampicillin sodium
0.465
Amoxicillin
0.391
Cefazolin sodium
2.442
Cefazolin organism
1.093
Oxygen piperazine penicillin
0.584
Ketoconazole
8.00
Vitamin B6
0.502
Fluorine organism acid
10.00
Praziquantel
0.667
Thiotepa
1.970
Penicillamine
1.290
Berberine hydrochloride
0.030
Verapamil
0.540
Alprazolam
3.950
Adjacent benzene acetic acid
0.010
2. Triethylamine is a base used to prepare esters and amides from acyl chlorides as well as in the synthesis of quaternary ammonium compounds. It acts as a catalyst in the formation of urethane foams and epoxy resins, dehydrohalogeantion reactions, acid neutralizers for condensation reactions and Swern oxidations. It finds application in reverse phase high-performance liquid chromatography (HPLC) as a mobile-phase modifier. It is also used as an accelerator activator for rubber, as a propellant, as a corrosion inhibitor, as a curing and hardening agent for polymers and for the desalination of seawater. Furthermore, it is used in the automotive casting industry and the textile industry.
Production
It is produced by ethanol and ammonia in the presence of hydrogen, in containing Cu-Ni-clay catalyst reactor under heating conditions (190 ± 2 ℃ and 165 ± 2 ℃) reaction. The reaction also produces ethylamine and diethylamine, products were condensed and then absorption by ethanol spray to obtain crude triethylamine, through the final separation, dehydration and fractionation, pure triethylamine is obtained.
Reaction
It can be used to reduce the alkali in the reaction.
Alkylation reaction
Oxidation reaction
Health Effects
Triethylamine is a flammable liquid and a dangerous fire hazard. It can affect you when inhaled and by passing through the skin. Contact can severely irritate and bum the skin and eyes with possible eye damage. Exposure can irritate the eyes, nose and throat. Inhaling can irritate the lungs. Higher exposures may cause a build-up of fluid in the lungs (pulmonary edema), a medical mergency. It may cause a skin allergy and affect the liver and kidneys.
Chemical Properties
Triethylamine is a colorless to yellowish liquid with a strong ammonia to fish-like odor. It is a base commonly used in organic chemistry to prepare esters and amides from acyl chlorides. Like other tertiary amines,it catalyzes the formation of urethane foams and epoxy resins.
Physical properties
Clear, colorless to light yellow flammable liquid with a strong, penetrating, ammonia-like odor.
Experimentally determined detection and recognition odor threshold concentrations were <400
μg/m3 (<100 ppbv) and 1.1 mg/m3 (270 ppbv), respectively (Hellman and Small, 1974). An odor
threshold concentration of 0.032 ppbv was determined by a triangular odor bag method (Nagata
and Takeuchi, 1990).
Application
Triethylamine (TEA, Et3N) is an aliphatic amine. It is used to catalytic solvent in chemical synthesis; accelerator activators for rubber; wetting, penetrating, and waterproofing agents of quaternary ammonium types; curing and hardening of polymers (e.g., corebinding resins); corrosion inhibitor; propellant.Triethylamine has been used during the synthesis of:5′-dimethoxytrityl-5-(fur-2-yl)-2′-deoxyuridine3′-(2-cyanoethyl)diisopropylphosphoramidite-5′-dimethoxytrityl-5-(fur-2-yl)-2′-deoxyuridinepolyethylenimine600-β-cyclodextrin (PEI600-β-CyD)It may be used as a homogeneous catalyst for the preparation of glycerol dicarbonate, via transesterification reaction between glycerol and dimethyl carbonate (DMC).
Production Methods
Triethylamine is prepared by a vapor phase reaction of ammonia with ethanol or reaction of N,N-diethylacetamide with lithium aluminum hydride (Windholz et al 1983). It may also be produced from ethyl chloride and ammonia under heat and pressure (Hawley 1981) or by vapor phase alkylation of ammonia with ethanol (HSDB 1988). U.S. production is estimated at greater than 22,000 tons in 1972 (HSDB 1988).
Definition
ChEBI: Triethylamine is a tertiary amine that is ammonia in which each hydrogen atom is substituted by an ethyl group.
Aroma threshold values
High strength odor, fishy type; recommend smelling in a 0.01% solution or less.
General Description
Triethylamine appears as a clear colorless liquid with a strong ammonia to fish-like odor. Flash point 20°F. Vapors irritate the eyes and mucous membranes. Less dense (6.1 lb / gal) than water. Vapors heavier than air. Produces toxic oxides of nitrogen when burned.
Reactivity Profile
Triethylamine reacts violently with oxidizing agents. Reacts with Al and Zn. Neutralizes acids in exothermic reactions to form salts plus water. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen may be generated in combination with strong reducing agents, such as hydrides.
Health Hazard
Vapors irritate nose, throat, and lungs, causing coughing, choking, and difficult breathing. Contact with eyes causes severe burns. Clothing wet with chemical causes skin burns. Triethylamine may also be irritating to skin and mucous membranes (Windholz et al 1983).
Fire Hazard
Flammable/combustible material. May be ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water.
Industrial uses
Triethylamine is used as an anti-livering agent for urea- and melamine-based enamels and in the recovery of gelled paint vehicles (HSDB 1988). It is also used as a catalyst for polyurethane foams, a flux for copper soldering, and as a catalytic solvent in chemical synthesis (Hawley 1981). Triethylamine is used in accelerating activators for rubber; as a corrosion inhibitor for polymers; a propellant; wetting, penetrating, and waterproofing agent of quaternary ammonium compounds; in curing and hardening of polymers (i.e. core-binding resins); and as a catalyst for epoxy resins (Hamilton and Hardy, 1974).
Biochem/physiol Actions
Triethylamine is known to drive polymerization reaction. It acts as a source of carbon and nitrogen for bacterial cultures. Triethylamine is used in pesticides. Triethylamine can serve as an organic solvent.
Safety Profile
Moderately toxic by
ingestion and skin contact. Mildly toxic by
inhalation. Human systemic effects: visual
field changes. Experimental reproductive
effects. Mutation data reported. A skin and
severe eye irritant. Can cause kidney and
liver damage. A very dangerous fire hazard
when exposed to heat, flame, or oxidizers.
Explosive in the form of vapor when
exposed to heat or flame. Complex with
dinitrogen tetraoxide explodes below 0°C
when undduted with solvent. Exothermic
reaction with maleic anhydride above 150°C.
Can react with oxidzing materials.
Incompatible with N2O4. To fight fire, use
CO2, dry chemical, alcohol foam. When
heated to decomposition it emits toxic
fumes of NOx.
Potential Exposure
Triethylamine is and aliphatic amine
used as a solvent; corrosion inhibitor; in chemical synthesis;
and accelerator activators; paint remover; base in methylene
chloride or other chlorinated solvents. TEA is used to solubilize
2,4,5-T in water and serves as a selective extractant in
the purification of antibiotics. It is used to manufacture quaternary
ammonia compounds and octadecyloxymethyltriethylammonium
chloride; an agent used in textile treatment.
Carcinogenicity
TEA was not mutagenic in bacterial assays,
but it did cause aneuploidy and chromosome
aberrations in rats.
Environmental fate
Photolytic. Low et al. (1991) reported that the photooxidation of aqueous tertiary amine
solutions by UV light in the presence of titanium dioxide resulted in the formation of ammonium
and nitrate ions.
Chemical/Physical. Triethylamine reacted with NOx in the dark to form diethylnitrosamine. In
an outdoor chamber, photooxidation by natural sunlight yielded the following products:
diethylnitramine, diethylformamide, diethylacetamide, ethylacetamide, diethylhydroxylamine,
ozone, acetaldehyde, and peroxyacetyl nitrate (Pitts et al., 1978).
Metabolism
There have been few studies on the metabolism of industrially important aliphatic amines such as triethylamine. It is generally assumed that amines not normally present in the body are metabolized by monoamine oxidase and diamine oxidase (histaminase).Ultimately ammonia is formed and will be converted to urea. The hydrogen peroxide formed is acted upon by catalase and the aldehyde formed is thought to be converted to the corresponding carboxylic acid by the action of aldehyde oxidase (Beard and Noe 1981).
Shipping
UN1296 Triethylamine, Hazard Class: 3; Labels:
3-Flammable liquid, 8-Corrosive material.
Purification Methods
Dry triethylamine with CaSO4, LiAlH4, Linde type 4A molecular sieves, CaH2, KOH, or K2CO3, then distil it, either alone or from BaO, sodium, P2O5 or CaH2. It has also been distilled from zinc dust, under nitrogen. To remove traces of primary and secondary amines, triethylamine has been refluxed with acetic anhydride, benzoic anhydride, phthalic anhydride, then distilled, refluxed with CaH2 (ammonia-free) or KOH (or dried with activated alumina), and again distilled. Another purification method involved refluxing for 2hours with p-toluenesulfonyl chloride, then distilling. Grovenstein and Williams [J Am Chem Soc 83 412 1961] treated triethylamine (500mL) with benzoyl chloride (30mL), filtered off the precipitate, and refluxed the liquid for 1hour with a further 30mL of benzoyl chloride. After cooling, the liquid was filtered, distilled, and allowed to stand for several hours with KOH pellets. It was then refluxed with, and distilled from, stirred molten potassium. Triethylamine has been converted to its hydrochloride (see brlow), crystallised from EtOH (to m 254o), then liberated with aqueous NaOH, dried with solid KOH and distilled from sodium under N2. [Beilstein 4 H 99, 4 I 348, 4 II 593, 4 III 194, 4 IV 322.]
Incompatibilities
A strong base. Violent reaction with
strong acids; halogenated compounds; and strong oxidizers.
Attacks some forms of plastics, rubber and coatings.
Corrosive to aluminum, zinc, copper, and their alloys in the
presence of moisture. Reaction with nitrosating agents
(e.g., nitrites, nitrous gases, and nitrous acid) capable of
releasing carcinogenic nitrosamines.
Waste Disposal
Controlled incineration
(incinerator equipped with a scrubber or thermal unit to
reduce nitrogen oxides emissions).
Check Digit Verification of cas no
The CAS Registry Mumber 121-44-8 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 1,2 and 1 respectively; the second part has 2 digits, 4 and 4 respectively.
Calculate Digit Verification of CAS Registry Number 121-44:
(5*1)+(4*2)+(3*1)+(2*4)+(1*4)=28
28 % 10 = 8
So 121-44-8 is a valid CAS Registry Number.
InChI:InChI=1/C6H15N.H2O4S/c1-4-7(5-2)6-3;1-5(2,3)4/h4-6H2,1-3H3;(H2,1,2,3,4)
121-44-8Relevant articles and documents
-
Uffer,Schlittler
, p. 1397,1399 (1948)
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Structure and dynamic behavior of phosphine gold(I)-coordinated enamines: Characterization of α-metalated iminium ions
Sriram, Madhavi,Zhu, Yuyang,Camp, Andrew M.,Day, Cynthia S.,Jones, Amanda C.
, p. 4157 - 4164 (2014)
Cationic gold(I) enamine complexes with the (t-Bu)2(o-biphenyl) phosphine ligand were isolated and characterized by NMR spectroscopy and X-ray crystallography. The complexes display highly distorted coordination modes that are consistent with characterization as α-metalated iminium ions. The barrier to rotation around the formal enamine C-C double bond has been measured in a geminally disubstituted enamine complex, and it is comparable to the barrier to C-C single-bond rotation in electronically restricted alkanes. With additional substitution on the enamine double bond, the complexes remain highly distorted, and the reaction of a mixture of E and Z enamines results in formation of a stereochemically pure gold complex. A survey of binding constants reveals enamines to be significantly stronger donors than any alkenes examined to date, and in the case of a geminally disubstituted enamine, the coordination is stronger even than that of triethylamine. The high stability drives the isomerization of an internal enamine complex generated from an intramolecular hydroamination reaction, to the exocyclic double-bond isomer.
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Lehmkuhl,H.,Reinehr,D.
, p. 215 - 220 (1973)
-
Absolute rate constants for some reactions of the triethylamineboryl radical and the borane radical anion
Sheeller, Brad,Ingold, Keith U.
, p. 480 - 486 (2001)
Laser flash photolysis (LFP) of dj-tert-butyl peroxide or dicumyl peroxide at ambient temperatures in the presence of Et3N→BH3 or BH4- generated the title radicals which were found to have broad, featureless absorptions in the visible region. Rate constants for H-atom abstraction from Et3N→BH3 by cumyloxyl radicals show a small solvent dependence, e.g. 12 × 107 and 2.2 × 107 dm3 mol-1 s-1 in isooctane and acetonitrile, respectively. Rate constants for halogen atom abstraction by Et3N→BH2. and BH3.- from a number of chlorides and bromides were determined by LFP and by competitive kinetics, e.g., for Et3N→BH2. + CCl4/PhCH2Cl/CH3(CH2)2Cl, k = 4.4 × 109/1.1 × 107/5.1 × 105 dm3 mol-1 s-1 and for BH3.- + CCl4/PhCH2Cl, k = 2.0 × 109/3.0 × 107 dm3 mol-1 s-1. Rates of addition of Et3N→BH2. to 1-and 1,1-substituted olefins increase dramatically as the electron affinity of the olefin increases, confirming the nucleophilic character of amine-boryl radicals. A comparison of the present results with literature data for the addition of olefins of four nucleophilic carbon-centered radicals proves that Et3N→BH2. is by far the most nucleophilic radical for which kinetic data are available. A few rate constants for abstraction of hydrogen from electron-deficient carbon by Et3N→BH2. are also reported.
Reactions of diethylamine and ethylene catalyzed by PtII or Pt0 - Transalkylation vs. hydroamination
Dub, Pavel A.,Bethegnies, Aurelien,Poli, Rinaldo
, p. 5167 - 5172 (2011)
PtBr2/nBu4PBr (without solvent) or K 2PtCl4/NaBr (in water) have been shown to efficiently catalyze the hydroamination of ethylene by aniline and are poor catalysts for the hydroamination of ethylene by diethylamine. A DFT study on the hydroamination mechanism indicates that the energetic span of the C 2H4/Et2NH catalytic cycle is close to that of the C2H4/PhNH2 cycle. The poor performance is attributed to rapid catalyst degradation with reduction to metallic platinum. Pt0, on the other hand, catalyzes a transalkylation process, partially transforming Et2NH into Et3N, EtNH2 and NH3. This process is inhibited by C2H4. Mechanistic considerations for the Pt0-catalyzed transalkylation process are presented. Copyright
Validated HPLC and stability-indicating densitometric chromatographic methods for simultaneous determination of camylofin dihydrochloride and paracetamol in their binary mixture
Abdel Razeq, Sawsan A.,Khalil, Israa A.,Mohammd, Samah A.
, p. 2587 - 2597 (2020)
Two accurate, sensitive, precise and selective HPLC and stability-indicating TLC methods were developed for the simultaneous determination of camylofin-2HCl and paracetamol. Forced acid, alkali and oxidative degradation of camylofin-2HCl?were tried where complete degradation was achieved using 5?N HCl. HPLC method was developed to determine the mixture of the two drugs using Zorbax NH2 column and a mobile phase of 0.5percent triethylamine and pH 3.0 adjusted with 0.1percent phosphoric acid and methanol (70:30 v/v) over concentration ranges of 3–90 and 10–95?μg/mL for camylofin-2HCl and paracetamol, respectively.TLC method was used for the separation of camylofin from its acid degradate and paracetamol using chloroform–methanol–acetone–conc. ammonia (8:2:2:0.1, by volume) as developing system and band scanning at 254 nm over concentration ranges of 5–40?μg/band for camylofin-2HCl and 0.1–0.5?μg/band for paracetamol. The validation of two methods was carried out according to ICH guideline. Accuracy ranged between 98.47 and 100.67percent for the two methods with acceptable precision RSDpercent ranging between 0.66 and 1.47percent.
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Hawthorne,M.F.,Budde,W.L.
, p. 5337 (1964)
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Effects of metal particle size in gas-phase hydrogenation of acetonitrile over silica-supported platinum catalysts
Arai, Masahiko,Takada, Yoshiomi,Nishiyama, Yoshiyuki
, p. 1968 - 1973 (1998)
The gas-phase hydrogenation of acetonitrile was studied with silica-supported platinum catalysts of which the degrees of metal dispersion were widely changed by reduction conditions. The activities were found to decrease gradually during the course of reaction for all the catalysts examined. The initial rate of reaction increased with an increase in the degree of platinum dispersion, D. Triethylamine was the only main product irrespective of D and period of reaction time. The initial turnover frequency, TOF0, was shown to be smaller for larger D values. This dependence of TOF0 on D was explained by the electronic state of the surface of the platinum particles and the state of acetonitrile molecules adsorbed on them on the basis of X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy measurements. The surface layer of smaller particles is more favorable for the adsorption of acetonitrile. The acetonitrile is adsorbed by platinum with the electron lone pair of nitrogen in the antibonding orbital, but electron back-donation does not takes place. As a result, the C≡N bonds of acetonitrile adsorbed on smaller particles are stronger and more difficult to hydrogenate.
High-Mobility Ions in Cyclohexane. A Transient Absorption Study
Shkrob, I. A.,Sauer, M. C.,Trifunac, A. D.
, p. 7237 - 7245 (1996)
Transient absorption kinetics in radiolysis of N2O-saturated cyclohexane has been studied (0.1 - 100 ns; 300 - 800 nm).The spectra indicate the involvement of at least three cations (ions I, II, and III), only one of them having abnormally high mobility.Ion II is probably the cyclohexene radical cation, and ion III might be the dimer olefin ion.These two ions absorb as much as ion I at 450 - 500 nm.While ion II and ion III are scavenged by ethanol and triethylamine with a rate constant of ca. 1E10 mol-1 dm3 s-1, the scavenging of ion I proceeds with rate constants of ca. 9E10 and 2.3E11 mol-1 dm3 s-1, respectively.The spectrum of ion I is similar to the spectrum of the radical cation of cyclohexane isolated in low-temperature matrices.We were not able to observe the absorption from ion I at delay times longer than 50 ns.A corresponding fast growth of the absorption from solute radical cations of pyrene and perylene was observed.The data (simulated using continuum-diffusion and Monte Carlo approaches) indicate that the scavenging constant is ca. 4E11 mol-1 dm3 s-1; the lifetime of the precursor of the aromatic radical cations is ca. 30 ns.This short lifetime cannot be explained by a reaction with radiolytic products or by homogeneous recombination, and it seems to be incompatible with identification of the long-lived high-mobility ions observed in conductivity experiments as the radical cation of cyclohexane.A mechanism in which the mobile radical cation is in equilibrium with a normally-diffusing ion is examined in an attempt to resolve this conundrum.
Ionic hydrogen bonds in bioenergetics. 4. Interaction energies of acetylcholine with aromatic and polar molecules
Deakyne, Carol A.,Meot-Ner, Michael
, p. 1546 - 1557 (1999)
The binding energies of the quaternary ions (CH3)4N+ and acetylcholine (ACh) to neutral molecules have been measured by pulsed high-pressure mass spectrometry and calculated ab initio, to model interactions in the acetylcholine receptor channel. Binding energies to C6H6 and C6H5CH3 are similar to those to H2O (33-42 kJ/mol (8-10 kcal/mol)), but are weaker than those to polar organic ligands such as CH3CO2CH3 (50-63 kJ/mol (12-15 kcal/mol)) and to amides (up to 84 kJ/mol (20 kcal/mol)). These data suggest that aromatic residues that line the groove leading to the ACh receptor site may provide stabilization comparable to water, and therefore allow entry from the aqueous environment, yet do not bind ACh as strongly as polar protein groups, and therefore allow transit, without trapping, to the receptor site. Four of the five distinct ACh conformers located computationally are stabilized by internal C-H...O hydrogen bonds involving the quaternary ammonium group, which is supported by the thermochemistry of the protonated analogue, CH3CO2CH2CH2N-(CH3) 2H+, and by the measured bonding energy between models of the ACh end groups, (CH3)4N+ and CH3CO2CH3. Each conformer forms a number of stable complexes with water or benzene. Several possible roles for an ACh conformational change upon entry into the channel are discussed, including partial compensation for the loss of bulk solvation. An additional role for the aromatic environment is also suggested, namely lowering the energy barrier to the formation of the active all-trans ACh rotamer required at the receptor site.
PHENYLPYRAZOLE COMPOUND AND METHOD FOR CONTROLLING PLANT DISEASE
-
, (2021/10/22)
The present invention provides a method for controlling a plant disease which comprises applying a compound represented by formula (I) [wherein Z represents a C1-C6 chain hydrocarbon group and the like, R1 and R2 are identical to or different from each other and represent a hydrogen atom or a fluorine atom, and R3, R4, R5, R6 and R7 are identical to or different from each other and represent a C1-C6 chain hydrocarbon group and the like] to a plant or a soil, which has excellent control efficacies against plant diseases.
Catalytic Deoxygenation of Amine and Pyridine N-Oxides Using Rhodium PCcarbeneP Pincer Complexes
Tinnermann, Hendrik,Sung, Simon,Cala, Beatrice A.,Gill, Hashir J.,Young, Rowan D.
, p. 797 - 803 (2020/03/13)
Rhodium PCcarbeneP pincer complexes 1-L (L = PPh3, PPh2(C6F5), PCy3) readily facilitate deoxygenation of amine and pyridine N-oxides. The resulting complexes exhibit δ2-C= O coordination of the resulting keto POP pincer ligand. These δ2-Ca? O linkages in the metalloepoxide complexes are readily reduced by isopropyl alcohol and various benzylic alcohols. Thus, efficient catalytic deoxygenation of amine and pyridine N-oxides is possible using complexes 1-L and isopropyl alcohol. This represents a pioneering example of PCcarbeneP pincer complexes being used as catalysts for catalytic deoxygenation.
