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The Importance of Canal Inclusion Compounds for Polymerization Research.

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than that of the OH group in the alcohols. The reason obviously is the bifunctional character of the oxime group. Only
two- and three-dimensional associates are formed, and these
have probably cyclic structures.
The
hydroperoxides are intericediate between the alcohols
The ligands in K2[Pd(CN)4] and K2[Pt(SCN)4] can be partly
and oximes. Like primary alcohols, primary hydroperoxides
or completely replaced by acetylide ions in liquid ammonia,
are more strongly associated than the secondary isomers;
giving the diamagnetic complexes cis-Bz[Pd(CN)z(C E C R ) ~ ]
these, however, are more similar to the corresponding oximes,
and KZ[Pt(C= CR)4], which are presumably planar.
i.e. their degree of association increases as the hydroperoxy
From theoretical considerations stabilization of the lower
group approaches the ceiiter of the molecule. Here again
oxidation states of central atoms by acetylide ions would be
only dimers and triiiiers are formed and hence it can be
expected. This was confirmed by the preparation of complex
concluded that hydroperoxides also associate bifunctionally
acetylides of Cr(O), Mo(O), W(O), Pd(0), Pt(O), and Cu(0). For
and probably form cyclic structures.
example the reaction
N o differences (within the accuracy of the methods) were
observed for isomeric carboxylic acids; they form only di+
[M(C0)3(NH3)3] + 3 KC-CR
meric associates, which are most stable.
3 NH3 $- K3[M(CO),(C=CR)3]
These results suggest that molccules which associate bi( 3 ) , M = Cr, Mo, or W
functionally tend t o form aggregates of only a few molecules,
i.e. mainly dimers and triniers; moreover, the dircers are all
i n liq. ammonia lead to the tricarbonyltrialkynylmetalates (0)
the more dominant, the stronger the hydrogen bonds. I n
(3). With potassium in liquid ammonia as reducing agent,
contrast, molecules which associate monofunctionally form
diamagnetic, pyrophoric, probably polynuclear acetylides(4)
mainly chains and three-dimensional networks containing
of Pt(0) and Pd(0) are abtained as follows:
many molecules. The thermodynamic excess functions for
the isomeric alcohols and oximes indicate that the position of
Kz[M(CN)41+ 2 KCECR 2 K + 4 K C N i K ~ M ( C E C R ) ~
the functional group in the chain has a considerable influence
(4),M = P d o r P t
on the short-range order. Polar and unsaturated solvents not
only suppress the association but also reduce the maximum
Finally, an orange-brown, pyrophoric, c:-ystalline phenylmultiplicity and alter the compositions of the associates.
acetylide complex (5) of formally zero-valent copper is pro[GDCh-Ortsverband Aachen (Germany),
duced by the reaction
November 6tn, 1964, and
01
GDCh-Ortsverband M i i n s c (Germany),
--f
2 Kz[Cu(C=C-C&&J + 2 Li + 3 Ba2@
Novembe; 9th, 19641
[ V B 88.51194 IE]
These anionic complexes are diamagnetic, sensitive to light,
and strong electrolytes in liquid ammonia. Analogous reactions with Ag2C2 and Au2C2 produced the polynuclear acetylides [KC-CAg],
and Kr[HC=C-Au-C-C-Au-C_CHJ.
+
0
Ba3[Cu(C=C-C6H5)3]2
+ 4 K O + 2 LiS
The diamagnetism of (5) and the position of its C=C band
in the infrared give evidence for a binuclear complex with a
Cu-Cu bond.
The infrared spectra of the complex acetylides of metals of the
Cr, Ni, Cu, and Zn groups indicate some double-bond character of the carbon-metal bonds, which decreases with increasing electronegativity of the central metal atom of the
complex. In the mixed alkynyl complexes of the Pd and Cr
groups, the carbonyl and cyano ligands can form much stronger d,-p, bonds to the metal than the acetylide ions.
[GDCh-Ortsverband Unterfranken, Wurzburg (Germany),
November 6th, 19641
[VB 8841190 I€]
German version: Angew. Chem. 77, 352 (1965)
Association of Isomeric Hydroxyalkane
Derivatives
G . Geiseler, Leipzig (Germany)
The tendency of isomeric alcohols, oximes, hydroperoxides,
and carboxylic acids derived from n-heptane and n-octane
to associate was studied in carbon tetrachloride by infrared
spectroscopy and thermodynamic methods. For the alcohols,
the degree of association decreases when the hydroxyl group
is shifted from a terminal position toward the middle of the
molecule. The heats of association for the different associates
(maximum multiplicity: 8-10 [I]) indicate that cyclic structures are present (at least for tri- and tetrameric associates) in
addition to chains and three-dimensional aggregates.
The oximes are much more strongly associated and behave
contrarily. The degree of association i n c r e a s e s as the hydroximino group approaches the center of the molecule, but the
influence of the position of the NOH group is less marked
[ I ] The term multiplicity denotes the number of monomers in a n
associate.
Aiigew. Chem. internnf. Edit.
Vol. 4(1965)
1 No. 4
German version: Angew. Chem. 77, 352 (1965)
The Importance of Canal Inclusion Compounds
for Polymerization Research
H. Clusen, FrankfurtiMain (Germany)
2,3-Dimethylbutadiene forms a canal inclusion compound
with thiourea; the dimethylbutadiene molecules lie head-totail in tube-like lattice interstices.AIthough dimethylbutadiene
does not polymerize without a catalyst outside these canals,
here it polymerizes spontaneously to form a n unbranched,
highmelting polymer which gives a crystalline X-ray diffraction pattern. This “canal polymerization” is accelerated by
X-rays.
After this and the canal inclusion compound of butadiene
became known [I], numerous monomers were examined for
their ability to undergo canal polymerization under the
influence of high-energy 9-and y-rays [2]. Cyclooctatetraene
will not form homopolymers, but will copolymerize with
dichlorobutadiene. - So far, stereoregular polymers could
be produced by irradiation only via canal inclusion compounds. Following recrystallization, their structures and
melting points are the same as those of stereoregular ZieglerNatta polymers. The yields increase with the duration of irradiation, but it is not yet known for certain whether the decrease in average molecular weight with increasing duration
of radiation and with increasing impurities can be explained
quantitatively by a monoradical reaction mechanism [3].
[I1 H. Clusen, Angew. Chem. 68, 493 (1956); 2. Eiektrochem.
Ber. Bunsenges. physik. Chem. 60, 982 (1956).
[2] J. F. Brown, and D.M . White, Angew. Chem. 70, 416 (1958);
J. Amer. chem. SOC.82, 5671 (1960); T . F. Yen, J. Polymer Sci.
38, 212 (1959); D. M. White, J. Amer. chem. SOC.82, 5678
(1960); Angew. Chem. 73, 175 (1961); I. Sukurudaand K. Numbu,
Nippon Kagaku Zasshi 80, 307 (1959); Chem. Abstr. 55, 4340
(1961); G. B. Burlow and A . C . Clamp, J. chem. SOC. (London)
1961, 393; 0. L . Glavuti and L . S . Poink, Petroleum Chemistry 2,
201 (1963).
[3] A. Yu.Temkin, Petroleum Chemistry 2, 210 (1963).
367
Uniform polymers would be expected in ideal single crystals
from purest monomers if the mechanism were a biradical one.
Perhydrotriphenylene functions as host not only for small
molecules, but also for unbranched macromolecules, which
form highly stable, even fusable canal inclusion compounds
[4). This affords a method of separating branched molecules
even in the macromolecular range and provides a means of
shielding macromolecular substances in order to prevent
undesired reactions. Graft polymerization in canals has not
yet been observed. Radioactive host substances which can be
regenerated are economically important.
[Lecture at Clausthal (Germany), November l3th, 19641
[VB 8751179 IE]
dcrgo thermal decomposition to give either fluoride and SO3
ox mostly oxide and pyrosulfurylfl uoride (the anhydride of
fluorosulfonic acid).
Characteristic reactions oT fluorosulfonic acid are illustrated
by its reaction with telluric acid (in the form of BaH4TeO6)
which leads to new compounds containing the FeSTe group.
The most interesting product is undoubtedly FjTeOH, m.p.
40 "C, b. p. 60 " C , a strong acid which can be used to produce
salts with the anion FjTeO" and other derivatives with the
FjTe group.
[GDCh-Ortsverband Saar, Saarbrucken (Germany), Deceniber I Ith, 19641
[VB 8901192 IE]
German version. Ansew. Chem. 77, 3 5 7 (19651
German version: Angew. Chem. 77, 353 (1965)
Hydrolysis of Metal Alkoxides -~
a New Method for Studying Polyacids
Valence Tautomerism of Unsaturated
Ring Systems
K. F. Johr, Berlin (Germany)
R. Huisgen, F. Mietzsch, G. Boche, and H. Seidl,
Miinchen (Germany)
The same kinetic method [S] which was used to prove the presence of 0.01 % bicyclo[4,2,0]octa-2,4,7-trienein equilibrium
with cyclooctatetraene by valence tautomerism was applied in the cyclooctatriene series. Kinetic investigations of
the Diels-Alder additions of pure cycloocta-1,3,5-triene and
of bicyclo[4,2,0]octadiene afforded all the parameters of the
free-energy diagram; the free energy of tautomerism is 1 . S
kcal/mole, and the activation energy for conversion into the
bicyclic compound is 27.1 kcallmole.
With substituted cycloocta-l,3,5-trienes the equilibrium concentration of the bicyclic tautonier at 20 " C strongly depends
on the nature of the substituents: It is 0.0072 for 7,g-epoxycycloocta-1,3,5-triene, 5 P:for cycloocta-2,4,6-trien- I-one, 9
for cycloocta-1,3,5-triene, and lOOx for 7,s-dibromocycloocta-l,3,5-triene.
The kinetics of the Diels-Alder reaction also indicate a valence tautomerism between trans-l,2-diphenylbenzocyclobutene and trans,trans-5,6-dibenzylidenecyclohexadiene
(u$diphenyl-o-quinodimethane), activation energy : 20.6 kcdl/
mole. Analogous ring opening of cis-l,2-diphenylbenzocyclobutene at 50 "C to give frans,cis-S,6-dibenzylidenecyclohexadiene proceeds seventy times as slow.
[GDCh-Ortsverband Mainz (Germany), November 26th,
19641
[VB 8911193 IE]
If a n ester of a metallic acid, e. g. Nb(OC2H5)j or
WO(OCzH&, is hydrolysed i n an organic solvent with less
than the equivalent amount of water in the presence of a n
anhydro base, a polyanion is formed which precipitates as
the salt of the base. The degrees of condensation and protonation of the polyanion are determined mainly by the p K
of the base.
Advantages of this new method are:
Fluorosulfonic acid is probably the most strongly protondonating solvent. The conductivities observed for solutions
of sulfuric acid, perchlorid acid, and hydrogen fluoride in
fluorosulfonic acid can best be interpreted by assuming that
these substances behave as bases. Only a few fluorides (SbFj,
BF3, PtF4, TaFS, and AuF3) behave as Lewis acids in fluorosulfonic acid. Correspondingly, many salts, particularly salts
of oxyacids, are solvolysed completely in FS020H. I n most
cases fluorides are subsequently formed, sometimes immediately in strongly exothermic reactions ( e . ~ . FMnO-,,
F2Cr02, F3P0, and F5TeOH), sometimes only on prolonged
heating (e.g. FCIO3, FzSe02, AsFj, and AsF3). I n addition
to the fluorides, fluorosulfates or fluorosulfate-fluorides may
occur as more or less stable intermediates, which in turn un-
1. The products are pure salts of the polyacids, without any
water of crystallization [I]; in organic solvents, the water
only causes hydrolysis and not hydration. Any water contained in the salts is exclusively part of the molecular structure.
2. It is possible to estimate quantitatively the amounts of the
metallic acid ester and of the anhydro base which react with
a given amount of water to form the salt of a polyacid. The
reactions leading to the various anionic species of the polyacid cdii then be formulated precisely. In particular, the ratio
of oxygen to metal atoms ( e . g . Nb or W) can be determined
for each polyanion, a factor which is indispensible for
structure determination.
3. Salts of polyacids can be obtained which would becompletely hydrolysed in aqueous solution.
4. Salts can be obtained of polyacids which are intermediates
in the hydrolysis reaction but which cannot be isolated from
aqueous solutions. During the hydrolysis of WO(OC2H15)4in
ethanol, the ammonium salt of hexameric "paratungstic acid
A ' was isolated for the first time [2]. In contrast to the ammonium salt of dodecameric "paratungstic acid 2'' (the
ammonium paratungstate which crystallizes from aqueous
solution in a highly hydrated form) the new salt is readily
soluble in water and exhibits all reactions characteristic of
the paratungstate A ion, which was hitherto known only in
solution; these reactions serve to distinguish it from the
paralungstate Z ion.
Oxyacids which condense with metallic acids also react
with the e s t e r s of metallic acids to give heteropolyacids 131. Thus, acidolysis of t-butyl orthovanadate
VO(OC4H9)3 with phosphoric acid in anhydrous organic
solvents leads to linear chains of alkoxyvanadatophosin which the
phoric acids, H-(I-IP03--V02-OR)n-P04H2,
vanadate and phosphate groups alternate. The alkoxyl
groups are hydrolysed with a little water, giving short-chain
vanadatophosphoric acids H-(HPO~-HVO~),-PO~HZ ( I ) .
The solubilities of ( I ) i n organic solvents decrease as the
length of the chains increases, and hence the chain extension
ceases as soon as the solubility becomes zero. The greater
the hydrophilicity of the solvent, the higher is the solu-
[4] M . Farina, G . Allegra, and G. Natta, J. Amer. chern. Soc. 56,
516 (1964).
[ 5 ] R . Huisgen and F. Mietzsch, Angew. Chern. 76, 36 (1964);
Angew. Chem. internat. Edit. 3 , 83 (1964).
[I] K . F. Jnhr and J. Fucks, Chern. Ber. 96, 2457, 2460 (1963).
121 P. Witte, Ph. D. Thesis, Freie Universitat Berlin, 1964.
[3] U. Skumia, Ph. D. Thesis, Freie Universitat Berlin, 1964.
x
German version: Angew. Chem. 77, 353 (1965)
Fluorosulfonic Acid as a Reaction Medium and
a Fluorinating Agent
A . Engelbrecht, Innsbruck (Austria)
368
Angew. Chem. internat. Edit.
1 Vol. 4 (1965) / No. 4
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