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Additions direct

salt and other ingredients are directly mixed into the dough. [Pg.723]


Molecules. The electronic configurations of molecules can be built up by direct addition of atomic orbitals (LCAO method) or by considering molecular orbitals which occupy all of the space around the atoms of the molecule (molecular orbital method). [Pg.152]

The potential advantages of LPG concern essentially the environmental aspects. LPG s are simple mixtures of 3- and 4-carbon-atom hydrocarbons with few contaminants (very low sulfur content). LPG s contain no noxious additives such as lead and their exhaust emissions have little or no toxicity because aromatics are absent. This type of fuel also benefits often enough from a lower taxation. In spite of that, the use of LPG motor fuel remains static in France, if not on a slightly downward trend. There are several reasons for this situation little interest from automobile manufacturers, reluctance on the part of automobile customers, competition in the refining industry for other uses of and fractions, (alkylation, etherification, direct addition into the gasoline pool). However, in 1993 this subject seems to have received more interest (Hublin et al., 1993). [Pg.230]

Finally, it should also be clear that ER reactions do not necessarily yield a gas-phase product. The new molecule may be trapped on the surface. There is evidence for an ER mechanism in the addition of incident Ft atoms to ethylene and benzene on Cii(l 11) [91], and in the abstraction of Ft atoms from cyclohexane by incident D atoms [92], and the direct addition of Ft atoms to CO on Rii(OOl) [93]. [Pg.914]

The bromine test is applied first. The organic compound, if a liquid, is treated with 2-3 drops of liquid bromine or (preferably) a solution of bromine in carbon tetrachloride if the organic compound is a solid, it should first be dissolved in cold carbon tetrachloride or chloroform. The rapid absorption of the bromine (and consequent disappearance of the red colour) is a strong indication that the compound is unsaturated, and is therefore undergoing direct addition of the bromine. [Pg.85]

By (he direct addition of hydrogen cyanide to aldehydes and ketones, giving cyanhydrins ... [Pg.121]

Dissolve 4 5 ml. of aniline in a mixture of 10 ml. of concentrated hydrochloric acid and 20 ml. of water cool the solution to 5°, and diazotise by the addition of 4 g. of sodium nitrite dissolved in 20 ml, of water, observing the usual precautions given on page 181. Dissolve 7 g. of 2-naphthol in 60 ml. of 10% sodium hydroxide solution contained in a 200 ml. beaker, and cool this solution to 5 by external cooling, aided by the direct addition of about 20-30 g. of crushed ice. Now add the diazotised solution very slowly to the naphthol solution, keeping the latter well stirred meanwhile the mixed solutions immediately develop a deep red colour, and the benzeneazonaphthol should... [Pg.210]

The reaction must be carried out in the absence of direct sunlight, since sunlight causes direct addition of the halogen to the hydrocarbon, particularly if the latter is warm benzene, for example, yields the hexahalide ... [Pg.533]

So without direct amination we are confined to semi-direct ami-nation (Strike s terminology). In Strike s opinion, the direct addition of an azide (N3) counts. Once on the beta carbon, that azide is as good as an amine. But can we get an azide directly onto safrole without having to go thru the bromosafrole intermediate as was discussed earlier Maybe we can ... [Pg.184]

This following article was sent to Strike by Osmium and Feck (are they the same person ). It involves the direct addition of azide to a terminal alkene (you-know-who) by the in situ production of the reactant mercury (II) azide from mercuric acetate and sodium azide (please don t ask) [80]. [Pg.184]

Direct addition of ammonia to olefmic bonds would be an attractive method for amine synthesis, if it could be carried out smoothly. Like water, ammonia reacts with butadiene only under particular reaction conditions. Almost no reaction takes place with pure ammonia in organic solvents. The presence of water accelerates the reaction considerably. The reaction of aqueous ammonia (28%) with butadiene in MeCN in the presence orPd(OAc)i and PhjP at 80 C for 10 h gives tri-2,7-octadienylamine (47) as the main product, accompanied by a small amount of di-2,7-octadienylamine (46)[46,47], Isomeric branched... [Pg.430]

The major product corresponds to addition of a proton at C 1 and bromide at C 2 This mode of addition is called 1,2 addition, or direct addition The minor product has its proton and bromide at C 1 and C 4 respectively of the original diene system This mode of addition is called 1,4 addition, or conjugate addition The double bond that was... [Pg.405]

Section 10 10 Protonation at the terminal carbon of a conjugated diene system gives an allylic carbocation that can be captured by the halide nucleophile at either of the two sites that share the positive charge Nucleophilic attack at the carbon adjacent to the one that is protonated gives the product of direct addition (1 2 addition) Capture at the other site gives the product of conjugate addition (1 4 addition)... [Pg.417]

This IS called direct addition ox 1 2 addition (The 1 and 2 do not refer to lUPAC locants but are used m a manner analogous to that employed m Section 10 10 to distin guish between direct and conjugate addition to conjugated dienes)... [Pg.777]

Conjugate addition is most often observed when the nucleophile (Y ) is weakly basic The nucleophiles m the two examples that follow are C=N and C6H5CH2S respectively Both are much weaker bases than acetylide ion which was the nucleophile used m the example illustrating direct addition... [Pg.777]

FIGURE 18 7 Nucleophilic addition to a p unsaturated aldehydes and ketones may take place either in a 1 2 or 1 4 manner Direct addition (1 2) occurs faster than conjugate addition (1 4) but gives a less stable product The product of 1 4 addition retains the carbon-oxygen double bond which is in general stronger than a carbon-carbon double bond... [Pg.778]

DuPont currentiy practices a butadiene-to-adiponittile route based on direct addition of HCN to butadiene (6—9). It was first commercialized in 1971. AH reactions are catalyzed by soluble, air and moisture sensitive, ttiarylphosphite-nickel(0) complexes. [Pg.220]

Both the hquid and cured 2-cyanoacryhc esters support combustion. These adhesives should not be used near sparks, heat, or open flame, or ia areas of acute fire ha2ard. Highly exothermic polymerization can occur from direct addition of catalytic substances such as water, alcohols, and bases such as amines, ammonia, or caustics, or from contamination with any of the available surface activator solutions. [Pg.179]

Borolane products of mixed composition can be synthesized by direct addition of boric acid to pentaerythritol (23). [Pg.464]

Sucrose Esters. These newer emulsifiers, approved for direct addition in the United States in 1983 (35), ate formed when sucrose is combined with various fatty acids and the resulting emulsion is dehydrated. These additives are odorless and tasteless, and can withstand the retort process. They are used in products when standards of identity do not preclude their use, such as baked goods, baking mixes, dairy product analogues, fto2en dairy desserts and mixes, and whipped milk products (39). High price has limited use in the United States, but these compounds ate used extensively in Japan as emulsifiers in baked goods (40). [Pg.438]

Gasification technologies for the production of high heat-value gas do not all depend entirely on catalytic methanation, that is, the direct addition of hydrogen to coal under pressure to form methane. [Pg.66]

The polymerization of monomers to form hydrocarbon resins is typically carried out by either the direct addition of catalyst to a hydrocarbon fraction or by the addition of feed to a solvent—catalyst slurry or solution. Most commercial manufacturers use a continuous polymerization process as opposed to a batch process. Reactor temperatures are typically in the range of 0—120°C. [Pg.351]

Manufacture. Phosphoms sulfochloride is manufactured by the direct addition of sulfur to phosphoms trichloride (50—52). At about 180°C, the reaction proceeds smoothly. Phosphoms trichloride vapor is passed through an excess of sulfur that is either molten or dissolved in an inert solvent. [Pg.370]

The final correlation for the overall boiling heat-transfer coefficient in pipes or channels (20) is a direct addition of the macroscopic (mac) and microscopic (mic) contributions to the coefficient ... [Pg.96]

Sorbates can be appHed to food by any of several methods, including direct addition, dipping in or spraying with an aqueous sorbate solution, dusting with sorbate powder, or addition to food packaging materials. The potassium salt is used in apphcations where high water solubiUty is desired. [Pg.286]

Bromine vapor forms CgBr [12079-58-2] by direct addition to weU-oriented graphite. Other halogen and mixed halogen compounds have been prepared. [Pg.572]

Pulp bleaching with chlorine dioxide is most often performed at an acidic pH, so that the final pH of the bleach Hquor is in the range of 2—5. Under these conditions, the residual concentration of chlorite and chlorate ions in the bleach Hquor are minimized and chloride ion is the predominant chlorine species in the spent bleach (77). In addition to direct addition to pulp in bleaching, chlorine dioxide also finds use in wastewater treatment from pulp mill operations as a means to remove effluent color (85). [Pg.484]

Ethyl Chloride. Previously a significant use for industrial ethanol was the synthesis of ethyl chloride [75-00-3] for use as an intermediate in producing tetraethyllead, an antiknock gasoline additive. Ethanol is converted to ethyl chloride by reaction with hydrochloric acid in the presence of aluminum or zinc chlorides. However, since about 1960, routes based on the direct addition of hydrochloric acid to ethylene or ethane have become more competitive (374,375). [Pg.416]

The effective friction loss, or gas-phase contacting power, is easily determined by direct measurements. However, the liquid-phase contacting power, supplied from the stream of scrubbing liquid, and the mechanical contacting power, supplied by a mechanically driven rotor, are not direc tly measurable the theoretical power inputs can be estimated, but the portions of these quantities effectively converted to contac ting power can only be inferred from comparison with gas-phase contacting power. Such data as are available indicate that the contributions or contacting power from different sources are directly additive in their relation to scrubber performance. [Pg.1592]


See other pages where Additions direct is mentioned: [Pg.187]    [Pg.208]    [Pg.292]    [Pg.168]    [Pg.230]    [Pg.623]    [Pg.419]    [Pg.419]    [Pg.365]    [Pg.465]    [Pg.102]    [Pg.221]    [Pg.286]    [Pg.295]    [Pg.534]    [Pg.296]    [Pg.465]    [Pg.471]    [Pg.135]    [Pg.300]    [Pg.261]    [Pg.1652]    [Pg.2059]   
See also in sourсe #XX -- [ Pg.367 ]

See also in sourсe #XX -- [ Pg.97 ]

See also in sourсe #XX -- [ Pg.85 ]




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1,4-addition directed

Addition charge-directed

Addition direction

Addition direction

Addition reactions direct

Addition reactions, gas-phase radical directive effects

Addition template-directed

Additional research directions

Alkenes heteroatom-directed addition

Alkoxide-directed 1,6-addition

Amines direct addition

Chelation directed addition

Chinensin via ortho directed addition

Direct Conjugate Additions via Enamine Activation

Direct Determination of Additives in Polymers and Rubbers

Direct Oxidative Addition of Magnesium to Organic Halides

Direct Oxidative Addition of Reactive Zinc to Functionalized Alkyl, Aryl, and Vinyl Halides

Direct additives

Direct additives

Direct additives to food

Direct and indirect food additives

Direct catalysis alkyne/alkene additions

Direct conjugate addition via C-H activation nonan-2-one

Direct ligand addition, transition metal

Direct potentiometry standard addition method

Direct potentiometry standard additions

Directed Conjugate Addition Reactions

Directed aldol addition

Directive effects in gas-phase radical addition reactions

Functionalized Grignard reagents direct oxidative addition

Hydrogen cyanide conjugate vs. direct addition

In Situ Direct Generation of Enolates and Their Asymmetric Aldol Addition Reactions

Incorporation of Liquid Additives and Dispersions by Direct Addition

Intramolecular addition reactions amines, direct irradiation

Organic halides direct oxidative addition

Oxazoline directed nucleophilic additions

Phosphoranes, acylcharge-directed conjugate addition

Preservatives Food Additives Directive

Proline-catalyzed direct aldol additions

Secondary direct additives

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