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Acetonitrile, compound with

Ethylamine, monoethylamine, CH3CH2NH2-B.p. 19 C. Prepared by reduction of acetonitrile or by heating ethyl chloride with alcoholic ammonia under pressure. It is a strong base and will displace ammonia from ammonium salts. Forms a crystalline hydrochloride and also crystalline compounds with various metallic chlorides. [Pg.166]

Heating of this latter compound with an excess of phenyl isothiocyanate in acetonitrile (65) leads to 2-phenylimino-3-phenyl-4-thioxo-se enazole[3.2-a]tetrahydro-s-triazin (Scheme 61). [Pg.260]

Generally it was found that resolution R is practically the same for isoeluotropic mixtures methanol and acetonitrile with water. The dependencies were obtained between capacity factors for derivatives of 3-chloro-l,4-naphtoquinone at their retention with methanol and acetonitrile. Previous prediction of RP-HPLC behaviour of the compounds was made by ChromDream softwai e. Some complications ai e observed at weak acetonitrile eluent with 40 % w content when for some substances the existence of peak bifurcation. [Pg.286]

Compounds with low flash points (below room temperature). Examples are acetaldehyde, acetone, acetonitrile, benzene, carbon disulfide, cyclohexane, diethyl ether, ethyl acetate and -hexane. [Pg.4]

A somewhat different approach is used to prepare the compounds containing the amine at the 4 position. Condensation of the amidine from acetonitrile (138) with the enol ether from formylacetonitrile (137) leads to the requisite pyrimidine (139). [Pg.128]

An example of a completely stereoselective cyclization of an allylsilane, leading to a seven-mem-bered ring in excellent yield, is known158. Treatment of the hydroxy compound with methanesulfonyl chloride and triethylamine in acetonitrile gives a single isomer of the bicyclic compound via cyclization of the (T )-iminium ion. [Pg.824]

NEt3 or DBU in acetonitrile. Similar condensations of O-silylated y9-dicarbonyl compounds with l,3-bis(trimethylsilyloxy)-l-methoxybutadiene (which is readily obtained by quenching of the anion of methyl 3-trimethylsilyloxybut-2-enoate with Me3SiCl 14, at -78 °C in CH2CI2, in the presence of Lewis acids such as TiCL ) likewise afford O-silylated methyl salicylates in high yields [40a-d]. [Pg.227]

Some advice can be formulated for the choice of organic modifier, (i) Acetonitrile as an aprotic solvent cannot interact with residual silanols, whereas the protic methanol can. Thus, when measuring retention factors, methanol is the cosolvent of choice, as it reduces the secondary interactions between the solutes and the free silanol groups, (ii) For the study of the performance of new stationary phases one should use acetonitrile, as the effects of free silanol groups are fuUy expressed [35]. (iri) Acetonitrile with its better elution capacity can be considered as the best organic modifier for Hpophilicity measurements of highly Hpophihc compounds with adequate stationary phases [36]. [Pg.337]

Superheated water at 100°-240 °C, with its obvious benefits of low cost and low toxicity, was proposed as a solvent for reversed-phase chromatography.59 Hydrophobic compounds such as parabens, sulfonamides, and barbiturates were separated rapidly on poly(styrene-divinyl benzene) and graphitic phases. Elution of simple aromatic compounds with acetonitrile-water heated at 30°-130 °C was studied on coupled colums of zirconia coated with polybutadiene and carbon.60 The retention order on the polybutadiene phase is essentially uncorrelated to that on the carbon phase, so adjusting the temperature of one of the columns allows the resolution of critical pairs of... [Pg.64]

Figure 2 Chromatogram of a polar (benzoic acid) compound with water acetoni-trile mobile phase. Chromatographic conditions — column 30 cm x 3.9 mm p-Bondapak C18 (10-pm particle size) mobile phase water acetonitrile (90 10) flow rate l.Oml/min column temperature ambient detector wavelength 254 nm. (A) No ion pairing agent. (B) With ammonium acetate as an ion pairing agent. Figure 2 Chromatogram of a polar (benzoic acid) compound with water acetoni-trile mobile phase. Chromatographic conditions — column 30 cm x 3.9 mm p-Bondapak C18 (10-pm particle size) mobile phase water acetonitrile (90 10) flow rate l.Oml/min column temperature ambient detector wavelength 254 nm. (A) No ion pairing agent. (B) With ammonium acetate as an ion pairing agent.
Substrate can be added to the cultures as a solid, a suspension, or a solution in DMSO, methanol, ethanol, acetonitrile or water. As the microbial culture generally has high tolerance toward organic solvents, there is less restriction on the choice and amount of solvent to be used for dispensing the substrate. Aqueous solubility of substrates normally will not affect compound loading, as a compound with poor aqueous solubility will likely be absorbed by the cells and still be subjected to biotransformation. [Pg.214]

An isomeric mixture of the pyridotriazine derivatives 129 and 130 was obtained in the reaction of 2-aminopyridine with perfluoro-5-azanon-4-ene 128 in the presence of triethylamine in acetonitrile. Compounds 129 and 130 were isolated in 40% and 13% yield, respectively, beside some side products (Equation 16) <2000JFC(103)105>. [Pg.237]

Dialkylation of 376 with 375 can also be done simply by using 2equiv of triethylamine in acetonitrile. Compound... [Pg.421]

The training set consisted of about 500 compounds from Pharmacia Corporation. Each compound was incubated at a fixed concentration for 60 min with a fixed concentration of protein at 37° C. The reaction was stopped by adding acetonitrile to the solution and, after centrifugation to remove the protein, the supernatant was analyzed using LC/MS and MS. Compounds with a final concentration >90% of the corresponding control sample were defined as stable, whereas compounds with final concentrations below 20% of the corresponding control were defined as unstable [20],... [Pg.417]

Compounds with high dielectric constants such as water, ethanol and acetonitrile, tend to heat readily. Less polar substances like aromatic and aliphatic hydrocarbons or compounds with no net dipole moment (e. g. carbon dioxide, dioxane, and carbon tetrachloride) and highly ordered crystalline materials, are poorly absorbing. [Pg.39]

Namely, the reaction of 2-thioxothiazolidin-4-one N-hexanoic acid (116) with 2,5-dimethyl-l-phenylpyrrol-3-carboxaldehyde (117) in methanol under the catalytic action of ethylenediamine diacetate (EDDA) yields 5-[(2,5-dimethyl-l-phenylpyrrol-3-yl)methylidene]-2-thioxothiazolidin-4-one N-hexanoic acid (118) in 79% yield. The hydroxamate derivative of 118 is prepared by reacting this compound with 0-(tetrahydro-2H-pyran-2-yl)hydroxylamine followed by treatment with p-toluenesulfonic acid in methanol to afford compound 121 in 60% yield. Esterification of compound 118 is carried out by using methyl iodide in acetonitrile in the presence of sodium carbonate to give compound 120. The 5-(cyclohexyl)methylidene analogue (119) is obtained in 42% yield by direct reaction of compound 116 with cyclohexanecar-boxaldehyde in methanol under the catalytic action of EDDA. [Pg.202]

The higher catalytic activity of the cluster compound [Pd4(dppm)4(H2)](BPh4)2 [21] (20 in Scheme 4.12) in DMF with respect to less coordinating solvents (e.g., THF, acetone, acetonitrile), combined with a kinetic analysis, led to the mechanism depicted in Scheme 4.12. Initially, 20 dissociates into the less sterically demanding d9-d9 solvento-dimer 21, which is the active catalyst An alkyne molecule then inserts into the Pd-Pd bond to yield 22 and, after migratory insertion into the Pd-H bond, the d9-d9 intermediate 23 forms. Now, H2 can oxidatively add to 23 giving rise to 24 which, upon reductive elimination, results in the formation of the alkene and regenerates 21. [Pg.87]

Tap water Extract compound with solid-phase extraction technique that uses a membrane impregnated with reverse-phase particles elute with acetonitrile LC Low ppb (pg/L) 82-93 Hagen et al. 1990... [Pg.109]

Obtained by both cyclic (100 mV s-1) and square-wave (10 Hz, Osteryoung-type) voltammetry in acetonitrile solution containing 0.1 mol dm-3 BuJNBF4 as supporting electrolyte. Solutions were 1 x 10-3 mol dm-3 in compound with reference to an Ag/Ag+ electrode (330 10 mV vs SCE) at 21 1°G b Anodic shift of the reduction waves of [57] in the presence of 1.0 equiv of the respective cationic species added as their perchlorate or hexafluorophosphate salts. "Anodic shift in the presence of 2.0 equiv of the respective cations. The second reduction wave of [57] became obscure or disappeared in the presence of more than 1 equiv of the respective cations. [Pg.44]


See other pages where Acetonitrile, compound with is mentioned: [Pg.68]    [Pg.68]    [Pg.338]    [Pg.72]    [Pg.200]    [Pg.204]    [Pg.188]    [Pg.306]    [Pg.272]    [Pg.986]    [Pg.86]    [Pg.163]    [Pg.163]    [Pg.986]    [Pg.337]    [Pg.875]    [Pg.260]    [Pg.952]    [Pg.158]    [Pg.156]    [Pg.242]    [Pg.269]    [Pg.277]    [Pg.306]    [Pg.179]    [Pg.330]    [Pg.445]    [Pg.225]    [Pg.206]   


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Chromium complex compounds with acetonitrile

With acetonitrile

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