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Pyridines complexation

Thiazole complex Color Pyridine complex Color... [Pg.127]

Halophenols without 2,6-disubstitution do not polymerize under oxidative displacement conditions. Oxidative side reactions at the ortho position may consume the initiator or intermpt the propagation step of the chain process. To prepare poly(phenylene oxide)s from unsubstituted 4-halophenols, it is necessary to employ the more drastic conditions of the Ullmaim ether synthesis. A cuprous chloride—pyridine complex in 1,4-dimethoxybenzene at 200°C converts the sodium salt of 4-bromophenol to poly(phenylene oxide) (1) ... [Pg.330]

Selectivity of propylene oxide from propylene has been reported as high as 97% (222). Use of a gas cathode where oxygen is the gas, reduces required voltage and eliminates the formation of hydrogen (223). Addition of carbonate and bicarbonate salts to the electrolyte enhances ceU performance and product selectivity (224). Reference 225 shows that use of alternating current results in reduced current efficiencies, especiaHy as the frequency is increased. Electrochemical epoxidation of propylene is also accompHshed by using anolyte-containing silver—pyridine complexes (226) or thallium acetate complexes (227,228). [Pg.141]

In sulfamation, also termed A/-sulfonation, compounds of the general stmcture R2NSO2H are formed as well as their corresponding salts, acid hahdes, and esters. The reagents are sulfamic acid (amido—sulfuric acid), SO —pyridine complex, SO —tertiary amine complexes, ahphatic amine—SO. adducts, and chlorine isocyanate—SO complexes (3). [Pg.74]

Paal-Knorr synthesis, 4, 118, 329 Pariser-Parr-Pople approach, 4, 157 PE spectroscopy, 4, 24, 188-189 photoaddition reactions with aliphatic aldehydes and ketones, 4, 232 photochemical reactions, 4, 67, 201-205 with aliphatic carbonyl compounds, 4, 268 with dimethyl acetylenedicarboxylate, 4, 268 Piloty synthesis, 4, 345 Piloty-Robinson synthesis, 4, 110-111 polymers, 273-274, 295, 301, 302 applications, 4, 376 polymethylation, 4, 224 N-protected, 4, 238 palladation, 4, 83 protonation, 4, 46, 47, 206 pyridazine synthesis from, 3, 52 pyridine complexes NMR, 4, 165... [Pg.819]

Sulfur trioxide pyridine complex [26412-87-3] M 159.2, m 155-165°, 175°. Wash the solid with a little CCI4 then H2O to remove traces of pyridine sulfate, and dry over P2O5 [Chem Ber 59 1166 1926 Synthesis 59 1979]. [Pg.479]

Because of the cost of pyridine the phosgenation process may be carried out with a mixture of pyridine and a non-hydrohalide-accepting solvent for the polymer and the growing complexes. Suitable solvents include methylene dichloride, tetrachlorethane and chloroform. Although unsubstituted aromatic hydrocarbons may dissolve the solvent they are not effective solvents for the acid chloride-pyridine complexes. [Pg.561]

The use of dimethyl sulfoxide-acetic anhydride as a reagent for the oxidation of unhindered steroidal alcohols does not appear to be as promising due to extensive formation of by-products. However, the reagent is sufficiently reactive to oxidize the hindered 11 j -hydroxyl group to the 11-ketone in moderate yield. The use of sulfur trioxide-pyridine complex in dimethyl sulfoxide has also been reported. The results parallel those using DCC-DMSO but reaction times are much shorter and the work-up is more facile since the separation of dicyclohexylurea is not necessary. Allylic alcohols can be oxidized by this procedure without significant side reactions. [Pg.238]

If homolytic reaction conditions (heat and nonpolar solvents) can be avoided and if the reaction is conducted in the presence of a weak base, lead tetraacetate is an efficient oxidant for the conversion of primary and secondary alcohols to aldehydes and ketones. The yield of product is in many cases better than that obtained by oxidation with chromium trioxide. The reaction in pyridine is moderately slow the intial red pyridine complex turns to a yellow solution as the reaction progresses, the color change thus serving as an indicator. The method is surprisingly mild and free of side reactions. Thus 17a-ethinyl-17jS-hydroxy steroids are not attacked and 5a-hydroxy-3-ket-ones are not dehydrated. [Pg.242]

There is continuous interest in cleavage of epoxides as a general method lor the preparation of fluorohydrins Epoxides are effectively cleaved under mild conditions by a 70% hydrogen fluoride-pyridine complex (Olah s reagent). The... [Pg.202]

Table 1. Cleavage of Glycidic Esters, Glycidic Amides, and Glycidic Nitriles by Hydrogen Fluoride-Pyridine Complex 110,11]... Table 1. Cleavage of Glycidic Esters, Glycidic Amides, and Glycidic Nitriles by Hydrogen Fluoride-Pyridine Complex 110,11]...
Tnfluoromethyl homoallyl alcohols also dehydrate easily with phosphorus oxychloride-pyridine complex, but it is very difficult to remove water from their saturated analogues by the same method [82] (equation 52)... [Pg.904]

A recently discovered (2) oxidizing system promises to become very important for the oxidation of acid-sensitive compounds. The reagent is chromium trioxide-pyridine complex, which may be isolated after preparation and employed in nonaqueous solvents (usually methylene chloride). A remarkable feature of the reagent is that good yields of aldehydes are obtained by direct oxidation of primary alcohols. The preparation of the reagent and its use are given. [Pg.3]

D. Oxidation with Chromium Trioxide-Pyridine Complex General Procedure... [Pg.5]

A 5% solution of chromium trioxide-pyridine complex in dry methylene chloride is prepared. The alcohol (0.01 mole) is dissolved in dry methylene chloride and is added in one portion to the magnetically stirred oxidizing solution (310 ml, a 6 1 mole ratio) at room temperature. The oxidation is complete in 5-15 minutes as indicated by the precipitation of the brownish black chromium reduction products. The mixture is filtered and the solvent is removed (rotary evaporator) leaving the crude product, which may be purified by distillation or recrystallization. Examples are given in Table 1.1. [Pg.5]

Chromium trioxide-pyridine complex (Chapter 1, Section I) EK... [Pg.161]

The pyridine complexes of osmium(III) result from reductive substitution... [Pg.68]

Complexes of other N-donors A range of pyridine complexes can be made [98]... [Pg.121]


See other pages where Pyridines complexation is mentioned: [Pg.89]    [Pg.128]    [Pg.133]    [Pg.143]    [Pg.82]    [Pg.584]    [Pg.585]    [Pg.641]    [Pg.710]    [Pg.747]    [Pg.921]    [Pg.403]    [Pg.227]    [Pg.229]    [Pg.230]    [Pg.230]    [Pg.231]    [Pg.496]    [Pg.63]    [Pg.43]    [Pg.210]    [Pg.128]    [Pg.130]    [Pg.256]    [Pg.178]    [Pg.182]    [Pg.5]    [Pg.65]    [Pg.263]    [Pg.768]   


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2,6-Dicarboxylate pyridine, complexes

2- pyridine complexes structure

2- pyridine reaction with platinum complexes

2- pyridine ruthenium complexes

2- pyridine with ruthenium complexes

2- pyridine, reaction complexes

2- pyridine, reaction with ruthenium complexes

2.4.6- Trivinylcyclotriboroxane-pyridine complex

4- pyridine, reaction with iron complexes

Acid/pyridine complexation, hydrogen bonding

Actinide complexes pyridines

Barium complexes pyridine oxide

Beneficial Micro Reactor Properties for Ni-Pyridine Complex Formations

Benzoyl chloride-pyridine complex

Bis (imino) pyridine Iron Complexes

Bond lengths pyridine complexes

Boron complexes pyridine oxide

Boron complexes, cationic with pyridine

Boron complexes, cations, with pyridine

Bromine complex compounds cations, with pyridine

CHROMIUM TRIOXIDE-PYRIDINE COMPLEX, preparation in situ

Cadmium complexes pyridine oxide

Calcium complexes pyridine oxide

Calcium complexes pyridines

Carbene complexes with pyridine

Charge-transfer complexes pyridine-halogen

Chromic oxide complexes with pyridine

Chromium complex compounds with pyridine

Chromium trioxide-pyridine complex

Chromium trioxide-pyridine complex Collins reagent)

Chromium trioxide-pyridine complex oxidant

Chromium trioxide-pyridine complex preparation

Cobalt complex compounds with pyridine

Cobalt complex compounds, anions with pyridine

Cobalt complexes pyridine

Complex heterocycles synthesis, pyridine

Complexation with pyridine

Complexes pyridine

Complexes pyridine

Complexes with Amine, Pyridine, and Stilbazole Ligands

Copper complexes pyridine oxide

Copper-pyridine complex

Cupric nitrate-Pyridine complex

Drivers for Performing Ni-Pyridine Complex Formations in Micro Reactors

Ferrocenyl complex, pyridine

Gallium complexes pyridine

Gold complexes pyridines

Halogens, complexation with pyridines

Hydrogen fluoride pyridine complex

II) Halide-Pyridine Complexes

Indium complexes pyridines

Iodine complex compounds, with pyridine

Iridium complex compounds anions, with pyridine, cis- and

Iridium complex compounds nonelectrolytes, with pyridine

Iridium complex compounds with pyridine, cis- and trans

Iridium pyridine-based complexes

Iron complex compounds cations, with pyridine

Iron complex compounds, anions with pyridine

Iron complexes pyridine

Iron complexes, nonelectrolytes with pyridine and isothiocyanate

Lanthanide complexes pyridine oxides

Lewis acid complexation with pyridines

Magnesium complexes pyridine oxide

Manganese complexes pyridine

Manganese complexes pyridine oxides

Manganese complexes, cation nonelectrolyte, with pyridine and

Mercury complexes pyridine oxide

Molecular complexes bromine-pyridine

Molybdenum carbonyl complexes pyridine

Ni-Pyridine Complex Formations Investigated in Micro Reactors

Nickel complexes, reaction with pyridines

Nickel-Pyridine complexes

Of pyridine complexes

Organometallic complexes pyridine

Osmium complexes, reaction with pyridines

Osmium tetroxide-pyridine complexes

Oxidation with Chromium Trioxide-Pyridine Complex

Palladium complexes pyridine ligands

Palladium complexes pyridine oxides

Pincer-pyridine complexes

Platinum complex compounds with pyridine

Platinum complex compounds with pyridine, cis- and trans

Platinum complexes pyridine

Pyridine N-oxide complexes

Pyridine and Imine Complexes

Pyridine based complexes

Pyridine boron trifluoride complex

Pyridine chemisorption, complexes

Pyridine chromium tricarbonyl complexes

Pyridine complex with

Pyridine complex with borane

Pyridine complex with chromium trioxide (Collins

Pyridine complexes Ruthenium blues

Pyridine complexes electrolysis

Pyridine complexes linkage isomers

Pyridine complexes with boron

Pyridine complexes with metals

Pyridine complexes, lanthanide

Pyridine complexes, polymer-bound

Pyridine cyclodextrin inclusion complexes with

Pyridine derivatives complexes

Pyridine dipyridine complex

Pyridine hexafluoroacetone complex

Pyridine hexafluoroacetone complex lithiation

Pyridine iridium complexes

Pyridine molecular complex with bromine

Pyridine molybdenum complex

Pyridine nucleotide coenzymes, complexes

Pyridine nucleotide complexes

Pyridine oxide complexes

Pyridine oxide complexes, osmium

Pyridine polynuclear complexes

Pyridine sulfur trioxide complex ring opening

Pyridine sulphur trioxide complex

Pyridine transition metal complexes

Pyridine, 2- -, palladium complex

Pyridine, 2- 1-oxide metal complexes

Pyridine, 2-vinylhydroesterification catalysts, cobalt complexes

Pyridine, 3,5-dimethyl-, palladium complex

Pyridine, 3-bromo-, complex with

Pyridine, 4-substituted, complexes with

Pyridine, complex cations, with

Pyridine, complex cations, with chromium

Pyridine, complex cations, with iron

Pyridine, complexes with boron metals

Pyridine, complexes with non-metals—contd localization energies

Pyridine, complexes, with iridium

Pyridine, cyclodextrin inclusion complexes

Pyridine, methyl-2- metal complexes

Pyridine, osmium complex

Pyridine, reaction with rhenium complexes

Pyridine-2-carbaldehyde metal complexes

Pyridine-2-carboxamide metal complexes

Pyridine-2-carboxylic acid, formation metal complexes

Pyridine-2-sulfonic acid metal complexes

Pyridine-2-thiol, complexes with

Pyridine-2-thiol, complexes with complex

Pyridine-3,5-dicarboxylic acid, reaction complexes

Pyridine-Cu complex

Pyridine-SO3 complex

Pyridine-borane complex

Pyridine-bridged supramolecular complexes

Pyridine-derived transition metal complexes

Pyridines early transition metal complexes, reaction

Pyridines metal complexes

Pyridines, tetrahydrocarbene complexes

Pyridines, tetrahydrocarbene complexes reactions with diphenylacetylene

Pyridines, tetrahydrocarbene complexes synthesis

Pyridines, tetrahydrocarbene complexes via Diels-Alder reactions

Pyridine—halogen complexes, dissociation

Rare Earth Complexes with Pyridine Type Ligands

Rhenium complexes pyridines

Sarett oxidation chromium oxide/pyridine complex

Scandium complexes pyridine

Silver complex compounds, cations with pyridine

Silver complexes pyridines

Stability constants pyridine derivative complexes

Sulfur trioxide pyridine complex

Sulfur trioxide-pyridine complex/DMSO

Tantalum complexes, reaction with pyridines

Thallium complexes pyridines

Thorium complexes pyridine oxide

Titanium complexes, reaction with pyridines

Transition metals, complexes with pyridines

Tricarbonylchromium complexes pyridine

Vanadium complexes pyridine

With chromium trioxide-pyridine complex

Zirconium complexes pyridine

Zirconium complexes pyridine oxide

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