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Kinetics of Non-Isothermal Decompositions.

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2-bromopyridine, ?-fluoropyridine, dioxane, hexyl methyl
ether). The intermediate reaction of catalysts of the first
group with sulfamic acid occurs through x-bonds. These
catalysts have high polarity and low basicity; there is a
correlation between catalytic activity and basicity. The intermediate reaction of catalysts of the second group with sulfamic acid occurs through a-bonds. Catalysts of this group
have lower polarity than those of the first group; catalytic
activity is observed at sufficiently high basicity. Within this
group also there is correlation between catalytic activity and
basicity.
in the second step the desired sulfoxide is prepared by using
an alkylaluninum with a longer alkyl radical. Thus dichloroaluminum benzenesulfinate, obtained from ethylaluminum
dichloride and benzenesulfonyl chloride (1 : 1) in a first step,
reacts with di-n-hexylaluminum chloride t o give n-hexyl
phenyl sulfoxide in 61 7; yield. Tri-, di-, and mono-alkylaluminum compounds can all be used for these reactions;
monoalkylaluminum compounds are preferred because of
the greater utilization of the alkyl groups.
Concentration of Hemoglobin Solutions b y Flotation
Reaction of Sulfonyl Chlorides with
Alkylaluminum Compounds
J . Spurn9 and B . Jukoubek, Prague (Czechoslovakia)
Dilute solutions of hemoglobin can be concentrated by
foaming. We have studied pure hemoglobin solutions as well
as solutions to which a quaternary ammonium base has been
added (e.g. ethoxycarbonylpentadecyltrimethylammonium
chloride). The flotation time was not limited, so that the
simple relations
k f p = M R + ZVK
H . Rcinheckel and D . Juhnke, Berlin-Adlershof (Germany)
Triethylaluminum and ethylaluminum sesquichloride react
with aliphatic and aromatic sulfonyl chlorides in the molar
ratio 1 :1 in non-aromatic solvents such as methylene chloride, giving better than 95 % yields of the corresponding aliphatic and aromatic sulfinic acids and ethyl chloride. It is
and cpVp= C R V R + C K V K
assumed that electrophilic attack of the aluminum compound
on the sulfonyl chloride is followed by a synchronous process
hold, where Mp, MR, and MKare the total amounts of protein
in which the chlorine is removed cationically from the sulfur
dissolved in the original solution, i n the residual solution, and
and combines with the ethyl group (which has become
in the concentrate, respectively, cp, C R , and CK are the
negative) of the organoaluminum compound, yielding ethyl
corresponding concentrations, and Vp, VR, and V K are the
chloride. Hydrolysis of the aluminum sulfinate formed at the
corresponding volumes.
same time gives the corresponding sulfinic acid.
We
were interested particularly in the dilution of the initial
When twice the molar amount of organoaluminum comsolution and in the concentration range the method can be
pound is used, there is a characteristic difference between the
used, to what extent the protein content of the concentrate
modes of reaction of aliphatic and aromatic sulfonyl chlorcan be raised above that of the original solution, and what
ides. Either of the ethylaluminum compounds with aromatic
yields can be obtained. We consider that the quaternary
sulfonyl chlorides in the molar ratio 2 : 1 gives, besides ethyl
ammonium bases form complexes with proteins.
chloride, more than 75% of the corresponding ethyl sulfoxide and small amounts of ethyl sulfide. A second mole of
organoaluminum compound has no influence on the reaction
of aliphatic sulfonyl chlorides; the corresponding alkanesulfinic acid is always formed.
The electron density at the sulfur atom is considered respon5 x 10-7-1.0 x 10-4
0.96-10.3
sible for these differring modes of reaction. The aluminum With quat. base
79-98
sulfinate resulting from the first reaction step permits alkyl- (c 10-4 g/ml)
ation of the sulfur if the electron density on the latter is
For the concentration of pure hemoglobin solutions (withsufficiently reduced by an electron-attracting substituent for
out addition of quaternary salt) the following relations beattack by the negative ethyl group to be succesful. The same
tween volume of concentrate and concentration of the original
results attend the use of alkylaluminum compounds containsolution hold:
ing longer alkyl chains. Thus reaction of tri-n-hexylaluminum
VK = k’(cK - k )
with benzenesulfonyl chloride (2: 1) gives 70% of n-hexyl
phenyl sulfoxide.
and V K = Vp(cp - CK)/(CK- CR)
The economy of this one-stage process can be considerably
improved by carrying out the reaction in two independent
where k‘ and k are constants with the values 15.67~104
steps. In the first step a cheap alkylaluminum compound is
mP/g and 3 . 3 10-5
~ g/ml, respectively.
[VB 3 IEJ
used for preparation of the aluminum sulfinate, e.g. ethylGerman version: Angew. Chem. 78, 944 (1966)
aluminum dichloride or ethylaluminum sesquichloride; then
-
I I
-
+ 1:
Kinetics of Non-Isothermal Decompositions
and for n
By H. Juntgen [*I, Essen (Germany)
-=-.
dV
k o e- E / R T [ Vo-(n-l)
dT
m
Non-isothermal reactions in nature and in industry are
influenced by the variation of temperature with time. For
simplicity, investigations are confined to reactions at constant rates of heating. Some general equations have been
derived for this case. In particular, for the rate of gas evolution per unit temperature change, dV/dT ( V = volume of gas
formed up to temperature T ) in thermal decompositions as a
function of the temperature T, we find, for a reaction order
n = 1:
dV
dT
.-
=
5v0
exp
m
(
-
E
RT
koRT2 ,-E/RT
mE
- .--
Angew. Chem. internut. Edit.
/
Vol. 5 (1966) / No. 10
Em
The shapes and positions of the maxima of these functions
depend on the rate of heating m = dT/dt, the order n of the
reaction, the activation energy E, and the frequency factor
ko; the quantity VO(volume of gas evolved at t = a),being a
proportionality factor, simply produces a parallel displacement of the curves. If n is known, the quantities E and ko can
be determined from the observed gas formation at a given
rate of heating m by regression analysis with the aid of an
electronic computer. Whether or not n has been chosen
correctly can be judged from the correlation coefficient and
residual scatter.
903
8.6
The method was illustrated with the aid of three experimental
examples, in which finely divided samples with helium passing
through them were decomposed in a n accurately adjustable
oven at a constant rate of heating. The rate of gas formation
was determined from the measured constant flow rate of the
flushing gas and by continuous mass-spectrometric concentration measurements.
The reproducibility of the method was checked in the decomposition of basic magnesium carbonate. The figure shows
that the calculated rate of decomposition agrees closely with
that observed. The activation energy is 42.6 & 1.4 kcal/mole,
and the frequency factor is (3.7 i 0 . 5 ) ~1012 min-1, assuming
n = 1. The technically significant influence of the rate of
heating can be shown very clearly in the case of 4 MgC03Mg(OH)2.5HzO: at low rates of heating (m < lO"C/min),
the basic carbonate liberates COz directly between 400 and
450 "C, whereas at high rates of heating (m < 100 "Cjmin),
it is first converted into magnesite, and decomposes only
above 600 "C to give MgO.
4 /
300
\
LOO
500
The pseudo-unimolecular reduction of sulfuric acid to SO2
on activated coke, which is important in new flue-gas desulfurization processes, can also be represented as a firstorder reaction. An activation energy of 17 kcaljmole and a
frequency factor of 5x105 min-1 are obtained. For the firstorder decarboxylation of ferulic acid, which was studied
at a heating rate of 5.6OC/min, a n activation energy
of 27.7 kcal/mole and a frequency factor of 3 . 6 10-11
~
min-1
are found.
[Lecture at Heidelberg (Germany),
[VB 23 IE]
June 20th, 19661
Reactions of Strongly Electropositive Metals with
Graphite and with Metal Dichalcogenides
W. Riidorff, Tubingen (Germany)
Graphite reacts with solutions of alkali and alkaline-earth
metals in liquid ammonia, forming metal ammine-graphite
compounds. According to the concentration of the metal,
europium or ytterbium gives compounds ( [ C ~ ~ - ~ S I M ( N H ~ ) ~ ) ,
(2nd stage) and ([Cs]M(NH3)2), (1st stage) [I]. With graphite
the blue ammoniacal solutions of Be, Mg, Al, Ba, Ce, and
Sm prepared electrolytically with an anode of the appropriate metal give metal - graphite compounds such as
( [ C ~ O I M ~ ( N H ~ )(4th
Z - ~stage)
)~
and ([C1~1Sm(NH3)3), (2nd
stage). Further, compounds can be prepared having two
metals in an ordered layer structure, e.g. a 1st stage
([C,o]MgK2(NH3)), from a 4th stage magnesium-graphite
and potassium, or a 1st stage ([Clo]BeK0.62(NH3)), with
I, = 31 A [21 from a 5th stage beryllium-graphite. Electrolysis
with a uranium anode in the presence of K I leads to a graphite
containing uranium and potassium ([ClslUKo.ls(NH3)3),.
Magnetic measurements show that M2+ and M3+ ions are
present in ytterbium- and samarium-graphite, the proportion
of M3+ ions increasing with rising temperature, whereas
europium-graphite contains only E u ~ +ions. Europiumgraphite (1st stage), like the metal, shows strong dependence
of susceptibility on the field strength at low temperatures.
Sulfides such as MoS2, WS2, ReS2, and TiS2 that crystallize
with layer lattices, as well as the corresponding selenides,
react with metals dissolved in liquid ammonia. Compounds
such as Ko.sWS2, KO.STiS2, and NaTiSez are formed, in
which metal layers are intercalated between the MX2 layers.
The properties of these compounds (pyrophoric nature,
reaction with water with evolution of H2, magnetic behavior)
indicate that they are essentially intermetallic compounds.
The transition to ionic thiometalates can be followed in the
isostructural series N ~ O . S T ~ S ~ - N ~ V S Z - N (NaVS2,
~C~S~.
prepared from Na2S and V2S3, has the following properties:
black; slowly decomposed by water without evolution of H2;
la= 3.57 A, Ic = 19.68 A; p e =~ 2.1 BM at 293 'C; y. = 5.9
ohm-1 cm-1.
[Lecture at Hannover (Germany),
[VB 15 IE]
June 23rd, 19661
German version: Angew. Chem. 75, 948 (1966)
German version: Angew. Chem. 78, 948 (1966)
[l] In the first stage the metallic reactant forms a layer between
each pair o f graphite layers parallel to the basal plane of the
[*I K . H. van Heek, H. Jiintgen, and W. Peters, Ber. Bunsenges.
physik. Chem., in press; K . H. van Heek. Dissertation, Technische Hochschule Aachen, 1965.
lattice, in the second stage between each second pair of such
layers, and so on.
[2] Ic denotes the lattice parameter in the c-direction.
SELECTED ABSTRACTS
Photochemical formation of bicyclo[3.1.0]hex-2-ene and
extent greater than 0.3 %.With COz or HgBrZ the non-deuterated system (2) z(3) z(4)gives only open-chain products;
3-vinylcyclobutene was observed by J. Meinwald and P. H .
Mazzocchi on irradiation of ether solutions of 1,3-cyclohexause of D20 affords [4-D]-1,I-diphenyl-1-butene as sole
diene. The products were identified by mass, N M R , and IR
deuterated hydrocarbon (97 % yield). Equilibration is much
spectroscopy. It had previously been assumed that 1,3-cyclohexadiene gives only polymers and 1,3,5-hexatriene. / J. Amer.
Mg
( CsHs)zC= C H- CH2-CD2- M g B r
[Rd 540 IE] ( C s & h C = C H- CH2- CD2- B r
chem. SOC.88, 2850 (1966) 1 -Kr.
(CzHdzO
(1)
(2)
11.
The allylmethyl-cyclopropylmethyl rearrangement of the
F S H 5 ,CD2
Grignard reagent from [l ,l-Dz]-l-bromo-4,4-diphenyl-3( C ~ H ~ ) ~ C = C H - C D Z - C H ~a
- M ~ BrMg-C-HC,I
B~
butene ( I ) has been studied by M.E.H.Howden, A . Maercker,
(3)
CH2
(4)
J. Burdon, and J. D . Roberts. The solution of this organometallic compound (ether, 2OOC) shows a 1H-NMR specfaster ( r l / Z = 30 hr at 27OC) than when the phenyl subtrum corresponding to an equilibrium mixture of equal
stituents are not present (7112 = 30 hr at 27 "C). / J. Amer.
parts of compounds (2) and (4);the assumed intermediate
[Rd 532 IE]
chem. SOC.88, 1732 (1966) / -Eb.
(3) cannot be present in the equilibrium mixture to an
A&
904
Angew. Chem. internat. Edit.
/ Vol. 5 (1966) No. 10
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