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12




1 Complex Subject.


, , . The addition of bromine to a mixture of benzene, aluminium chloride, and sulfur is said to give a good yield of phenyl sulfide.

, 0,232 . The equilibrium constant was found to equal 0.232 and the data to jit more accurately into a formula.

, , . Other hexaarylethanes were soon found to be dissociated even more readily than hexaphenylethane.

, , , . It is common simply to heat the hydrazone, although this was reported to give a lower yield than reifluxing with acetic acid.

, - . No other substance has been reported to respond to the Corner-Allen or Clauberg test.

, . The whole reaction was thought to occur in one step.

, II , , I . Originally, substance II was thought to be the primary product of the reaction but it was subsequently shown to form the reaction of I with thiophene.

, - . The cis-isomer was shown to cyclise on treatment with acetic anhydride to the acetylpirrocolin.

, . The two columns are now supposed to operate at atmospheric outlet pressure.

, - . The rearrangements were alleged to be a threat in cases of acid catalyzed eliminations.

, . These two reactions can be assumed to occur predominantly by ionization.

, . This compound was discovered to have anaesthetic properties.

, , , , (). The model is then imagined to be flattened and the groups are laid on the plane


of the paper in the order that they appear in the model, as in (c).

(), , , . Two hydrogen atoms, a and b, are imagined to approach each other from infinity.

, . The surface of this portion of the catalyst was postulated to consist of cobalt atoms.

, . This observation has been interpreted to point to new facts.

3 000 000 . In Morocco alone, these deposits are estimated to contain 3 000 000 tons of uranium.

, , , . The probable error in the above pressure values is unknown, but estimated to be that shown.

, . Today phages are universally recognized to form a group of bacteria-specific viruses.

, . These high dipole moments are held to be evidence for the double bond nature of the phosphoryl group.

, . The isomers are deemed to be in dynamic equilibrium with one another.

, . The reaction can be inferred to take the following course.

, , , . Esters do not form disulfite addition products and are recognised from this and other facts to be significantly less reactive in additions than aldehydes and ketones.

, . This reaction may be represented to take place in the following steps.

, 8. 90. From their data the polarization is calculated to be 8. 90.

1934 . , . In 1934 the statement was retracted and the degradation products declared to be devoid of significant activity.


, . The high percentage of impurities was feared to lead to low yields.

212. - to turn out, to happen, to seem, to appear. to turn out , , to happen , to seem, to appear (-) .

:

, . This reaction turned out to be endothermic.

, . The above mentioned action of metallic sodium upon halobenzenes turned out to be rather useless from the mechanistic view-point compared with homogeneous reaction of aromatic substances with organolithium compounds.

-, , , . These correlations appear to hold, also, for many hydrocarbons.

To , -, . The same thing appears to be true of oxidations with other reagents.

To , -, . The same seems to be true of metal filaments.

, , -, . It has to be admitted that the conclusion does not always seem to be a logically inevitable one.

213. - to prove. . to prove - :

1) (. 209).

, . We proved this suggestion to be wrong;

2) (. 211) , .

, . This substance was proved to be extremely stable.

, . This fact may be proved to be of great importance. , . This product has been proved to affect the overall yield;


3) , .

, , . Such has indeed proved to be the case.

, . The diimine proved to be a colourless compound.

, , . Although at first sight both the alloy system and the chemical reaction seem relatively simple, both have proved to be complex.

214. --c: to be sure, to be certain, to be likely, to be unlikely, to be apt.

: to be sure, to be certain, to be likely, to be unlikely, to be apt, -, : , , , , (to be sure, to be certain); * (to be likely); , (to be unlikely).

:

, . This investigation is likely to produce good results.

, . The above mentioned reactions are certain to proceed smoothly.

() . This compound is sure to contain admixtures.

. This discovery is certain to lead to important results.

300. The explosion is unlikely to take place at 300.

, . The close agreement of the six compounds listed is unlikely to be a coincidence.

, . This reaction is unlikely to take place.

. to be likely , 1. :

, , -

1 . . . 3 , . . , . . . . . ., 1962, . 60.


. Such minerals are likely to occur in some other places as well, the probability of discovering them being however limited to certain areas.

. In volcanic regions hot-springs are likely to occur.

215. () as + - (). , , .

: + - + + as + (), + - + as + .

.

() + , () + as + , .

:

, . Kekule conceived valence as being a property of atoms and to be a constant for each element.

, . This catalyst was regarded as affording good results and to involve no difficulties in operating.

-, -, + as + + + as + , , .

:

, , XIII . The investigation of the reaction product of mesityl oxide with phosphorus trichloride in the presence of acetic anhydride gave the proved structure of the intermediate as being identical with the product discussed in Section XIII and obtained from diacetone alcohol.

, , d- 1-, . Hence, it is necessary to specify the solvent when speaking of a certain optical isomer as being the d-isomer or 1-isomer.

15 . . 225


, . The ammonia which is formed is established as representing the amide nitrogen of the protein molecule.

, 1,5 2, , 1520 . However, the separation is under total reflux, and so, using the safety factor of 1,5 to 2, we obtain 15 to 20 plates as being a safe value to use for the actual separation.

, X . X can be shown as containing admixtures.

, . X is postulated as arising from excessive heating.

, . This reaction is considered as being of great importance.

, , . Since the solid is strongly paramagnetic, it is regarded as having free radical structure.

, , , . This identifies the ring inquestion as being at the end of the molecule.

, . These observations point to the important problem of copolimer compositions as being a topic quite distinct from that of overall polymerisation kinetics.

, -- . They have therefore assigned the asymmetric P-O-P vibrations as being the origin of this absorption.

, 750 1 9: 10 725 -1 . Cannon and Sutherland identified bands at 750 -1 in 9: 10 dihydroanthracene and at 725 -2 in anthracene itself as being due to this vibration.

, -, , , . In general, it seems reasonable to picture the activated complex in a bimolecular reaction as having properties intermediate between the properties of the reactants and products.

, , , . The rate-determining step is pictured as being a unimolecular reaction.

, 1 2


. Eqn. 1 or 2 can be looked upon as determining the surface area in terms of the pore volume.

, - , . It is, however, necessary to point out that organic chemists have been accustomed to treat the strongest mineral acids as exerting the characteristic reaction of an alkali.

- , , , 56 58 . Because of the instability of the acid and the fact that it readily reacts with water, the melting point could be determined only approximately as being between 56 and 58 C.

, . Bohn obtained the blue dye and recognized the substance as having a condensed-ring system.

, , 80 000 , . A sediment obtained by centrifuging at a force of 80,000 times gravity was classified as consisting of asphaltenes.

, 2 . Reaction 2 a may be written as proceeding by the following mechanism.

, , 1639 1600 -1 , . The same authors have also put forward a second correlation which describes a strong band in the 16391600 cm-1 range as being characteristic of anilino structures in general and indolenines in particular.

, , , . Ions are sometimes spoken of as being in a transition state, but this is done as a matter of convenience rather than as a matter of accuracy.

, -, , 14201310 -1 The nitrose-group other than in nitrites is generally quoted as absorbing in the range 14201310 -1.

, . In the case of cumene the isomerization by the two-step procedure is visualized as occurring by the following mechanism.

216. - , by. -

15* 227


, by. :

1) (, , , , . .)....; 2) ( . .).... :

; , , , . All the substituted alkenylamines described were prepared primarily for examination as antihistamines; many were found by Mr. A. F. Green of this Laboratory to show high activity, one of the most active being Actidil.

, , . The second oxidation product of desoxysarsasapogenin is regarded by Simpson and Jacob as arising as follows.

, . Two members of the aporphine group have been found by Barger and Girardet to contain but three atoms of oxygen.

, d--10-. These salts were shown by analysis to consist of one mole of the base and one mole of the d-camphor-10-sulfonic acid.

, . Diazoanhydrides were shown by Bamberger to react vigorously with aromatic substrates.

, 3046O12. The results were interpreted by Arnaud as pointing to the formula C30H46O12.

, , . The reaction of chromium trichloride and phenylmagnesium bromide was found by W. Herwig to exhibit a completely different physical appearance when conducted in tetrahydrofuran.

, , Δ4-. The product has the properties of a lactone and was regarded by Sorm and Dykowa as Δ4-1-lactone.

, - .

The alcohol lignins were considered by Klason to be half-acetals of a trimeric coniferyl aldehyde.

. . , ,


, . The vinyl carbazole high polymers of good color prepared by low-temperature polymerization, using boron fluoride-etherate catalysts, were considered by I. G. Farben too difficult to mold, and too variable from lot to lot.

, (I) , . The nickel (I) complex is regarded by Nast and Kasperl as having bridging carbonyl groups, but Griffith et al. have drawn the opposite conclusion from the infrared evidence.

1894 . , , ; , - . The monohydroxy derivative cyclobutanol was described by Perkin (1894) as snowing the closest resemblance to the fatty alcohols containing the same number of carbon atoms; it might, indeed, be readily mistaken for n-butyl alcohol.

217. - . , - , , -.

:

, . These reactions were not thought to proceed very violently.

-, . did not seem to be tired.

, -, - - . In sulfuric acid even secondary-secondary or secondary-tertiary transfer does not seem to occur.

, -, . The mechanism of this old and technically important reaction does not seem to have been investigated.

, , . Sarkar, on the other hand, does not consider the reduction of Fehling solution to be a proof of the presence of an aldehyde group.


-, (: ). It does not seem premature to attempt a brief and comprehensive presentation of the high polymeric reactions in theory and practice.

, , , α-, -, , . Sodium hydroxide, while convenient in certain cases, e. g. with α-amino acids, does not appear to be as generally useful as triethylainine.

, , , , . The disulfides are, of course, well known, but are not thought of as related to the sulfenic esters.

. - . :

, . This observation is not likely to be of much value for structural diagnosis.

He , , . The introduction of alkyl groups is not to be construed as a reaction of lesser importance than in the benzene series.

He , , - . The point of view here presented is not to be regarded as suggesting that dehydrogenation of hexahydroaromatic compounds does not involve a planar adsorption of the six-membered ring molecules to be dehydrogenated.

218. -, to be (being).

, to be (being, having been). as + (). -.

:

, . This identity should not be regarded as apparent and arising from an oscillation of the valency electrons.

,


, ; , . The distinction between the two nitrogen atoms which this formula implies has no real existence, either nitrogen atom could be written as double bound to the carbon atom and carrying a positive charge.

, . New polyhydroxyanthraquinones were synthesized and some of them were found applicable as mordant dyes.

, , . A reactant is present in such large excess that its concentration can be deemed constant.

, , . Rosenfield considers the Kidd method superior to the Landsteiner and Miller procedure.

, . The reaction was considered restricted to nonterminal triple bonds.

, . The loss of area is believed due to a filling or blocking off of catalyst pores.

, , , , . The boiling point of the fraction assumed pure corresponded to the boiling points of known pure materials.

, , . recognized the substance as a glycoside and called it ouabain.

, . The vertical distance between these lines at the selected potential is taken as the wave height.





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