close

Вход

Забыли?

вход по аккаунту

?

Isolation of Higher Cyclooligoamides from Polyamides.

код для вставкиСкачать
and 7.75 T (protons of the two methylene groups); the peak
areas are in ratios of 5 :5 :2: 2: 2.
The hydrocarbon (2) reacts smoothly with 2 moles of Nbromosuccinimide to give a viscous oil which probably contains a dibromide. Dehalogenation of the oil with zinc powder
in refluxingl-butanol in the presence of a trace ofsolid sodium
hydroxide produces phenylbullvalene (3) [3] in 5-10% yield
[based on (2)]. It is advantageous to purify the crude dibromide before dehalogenation by chromatography on silica gel
(0.05-0.20 mm grain size) with ether/pentane. The crude
phenylbullvalene is purified by distillation in a suitable apparatus, e . g . a cold finger, and recrystallization from ethanol/
ether, and then melts at 74-76 "C.
On catalytic hydrogenation over Pd, (3) absorbs four
moles of hydrogen to yield a liquid, C16H22. The ultraviolet
spectrum of ( 3 ) in hexane has Amax at 262 mp. (E = 8500).
When heated briefly t o 300°C, (3) rearranges to P-phenylnaphthalene.
The N M R spectrum of ( 3 ) [4] varies with temperature. At
-40 "C, 5 phenyl protons can be detected as a singlet at 2.83 T,
5 olefinic protons as a multiplet at 4.177, and 4 aliph3tic
protons as multiplets around 7.27 T and 7.80 7. I t follows
from the ratio of 5 olefinic to 4 aliphatic protons that an
equilibrium mixture of isomers is present in which the phenyl
group is situated o n a doubly bonded carbon atom. At 90 "C
the NMR spectrum comprises a singlet at 2.85 7 and a singlet
(line width 4 cps) a t 5.727 in area ratios of 5:9. At higher
temperatures the nine bullvalyl protons have thus equivalent chemical shifts.
Preliminary experiments have shown that it is possible to
synthesize bromophenylbullvalene and t-butoxyphenylbullvalene by a method analogous to that used to prepare bromobullvalene and t-butoxybullvalene [5].
Received: June 16th, 1965
[ Z 7/831 IE1
German version: Angew. Chem. 77, 682 (1965)
[I ] Molecules which Undergo Fast Reversible Valence-Bond
Isomerizations, Part 8. Part 7: G. Schroder, J. F. M. Ofh, and
R. MerPnyi, Angew. Chem., in press.
121 G. Schroder, Chem. Ber. 97, 3 131 (1964). The cyclooctatetraene was kindly supplied by the Badische Anilin- & Soda-Fabrik
AG., Ludwigshafen (Germany).
[3] W. v. E. Doering and G. KIumpp synthesized ( 3 ) by a different
route. The properties of both samples are identical - particularly
theNMR properties; personal communication from Prof. Doering.
[4] The NMR spectra were taken by Dr. J. F. M. 0 t h and Dipl.Chem. R. MerPnyi, Union Carbide European Research Associates, Brussels (Belgium).
IS] G. Schroder, R. Merknyi, and J . F. M. 0 t h Tetrahedron
Letters 1964, 773; J . F. M . Oth, R . MerPnyi, J . Nielsen, and
G . Schroder, Chem. Ber., in press.
Synthesis of Aryl Iminomethyl Disulfides
sy
R'-f!!-N-R2
f 1)
+
R3-S-C1
(2)
-HCI
s-S-R3
R1-4
N-R~
(3)
(3a) : R1= Rz = R3 = C6H5, m.p. 82-83 "C
(36) : R1= CH3; R2= R3 = C6H5, m.p. 28-29 "C
(3c) : R1= R2 = CsH5; R3 = o-OzN-CsH4, m.p. 78 "C
assigned to a C = N valence vibration coupled with the remaining groups in the molecule. The peaks for (3a) lie at
1608 and I586 _c 1 cm-1; when (3a) is labelled with 97 % ISN,
the doublet mergestoasingleintense bandat15745 lcm-1[3].
Even thioamides which d o not form S-oxides react with
aromatic sulfenyl chlorides. For example, although n o Soxide can be detected after oxidation of N-isopropyl-C-(pnitrobenzoy1)thioformamide (4)with H z 0 [41,
~ ( 4 ) does react
with benzenesulfenyl chloride to give N-isopropylimino-pnitrobenzoylmethyl phenyl disulfide (5), m.p. 97-98 'C. The
structure of (5) was also proved by cleavage to (4) with
cyanide and by its infrared spectrum.
Phenyl a-Phenyliminobenzyl Disulfide (3a): A solution of
5.33 g of thiobenzanilide in 180 ml of anhydrous ether is
cooled to -15 OC, and 2.00 ml of pyridine is added. A solution of 3.61 g of benzenesulfenyl chloride in 50 ml of dry
ether is then added to the cold stirred solution over 30 min.
The reaction mixture is allowed to warm up to room temperature, and the pyridine hydrochloride which has separated is
filtered off and washed with dry ether. Evaporation of the
ether from the filtrate leaves an oily residue which crystallizes
within a few minutes. Recrystallization from ethanol affords
5.3 g (66 %) of pure (3a).
Received: June 18th, 1965
[Z 8/834IE]
German version: Angew. Chem. 77, 720 (1965)
[l] W. Walter, J. Curts, and H . Pawelzik, Liebigs Ann. Chem.
643, 29 (1961).
[2] J. Goerdeler and K. Doerk, Chem. Ber. 95, 389 (1962).
[3] In this connection cf. H . Fritzsche and W. Schulze, Z. Chem.
4, 105 (1964).
[4] K. D. Bode, Doctorate Dissertation, Universitat Hamburg
1964.
By Prof. Dr. W. Walter and Dipl.-Chem. P. M. Hell
Chemisches Staatsinstitut, Institut fur Organische Chemie,
Universitat Hamburg (Germany)
During the oxidation of thiobenzanilide or thioacetanilide ( I )
with hydrogen peroxide, oxygen adds onto the sulfur atom to
form thioanilide S-oxides 111.
We have found that the thioanilides ( I ) also react with arenesulfenyl chlorides (2) a t the sulfur atom to produce aryl
phenyliminomethyl disulfides.
In order to establish the constitution of (3), it had to be shown
that the R3S group did not become attached to the nitrogen
atom, for it is known that carboxamides react with sulfenyl
chlorides a t their nitrogen atom t o yield N-sulfenylcarboxamides 121. The presence of the disulfide bond was proved
by splitting (3) with cyanide, when the thioanilides ( I ) were
re-formed.
The C=N bond in (3) results in a doublet in their infrared
spectra in KBr between 1580 and 1640cm-1; this can be
696
Isolation of Higher Cyclooligoamides
from Polyamides [1,2]
By Dr. P. Kusch and Prof. Dr. H. Zahn
Deutsches Wollforschungsinstitut an der
Technischen Hochschule Aachen (Germany)
The cycloamides c[Cap]z-s, c[Und]z, cIB-AIl-3,
and
c[B-Seb] have been isolated from nylon-6, nylon-I 1, nylon6,6, and nylon-6,10, respectively [3]. We have now isolated
the higher cyclic oligoamides c[Cap]s-s, c[Und]3, c[B-A]4,
c[B-Seb]z, and the c[Dod]z contained in nylon-12, all on a
preparative scale by gel filtration of the polyamide extracts on
Sephadex G 25 [Pharmacia, Uppsala (Sweden)] and Bio-Gel
P I 0 [Bio-Rad Laboratories, Richmont, Calif. (U.S.A.)];
some of these compounds had previously been merely detected in the polymers by chromatography [4-61.
Angew. Chem. internat. Edit.
Vol. 4 (1965) I No. 8
c1Capls
c[Capl,
c[CapJs
c[Und]3
c[Dod]z
cIB-A]~
c[B--SebJz
P 10.
M.p. [ "Cl
Crystal form
260
243
254
184
212
273
225
Needles
Triangular platelets
Needles
Needles
Needles
Needles
Needles
served depends on the position of the association equilibrium.
The shift is especially strong in arnines and is hardly affected
Rl
R2>: + H-CCls
R
R
'
;
P
:R ~ % - - H - C C ~ ~
R3'
by alkyl groups R provided the latter do not cause steric
hindrance to the association; for example, 6 = 520 cps in
methylamine. If the alkyl groups exert a steric effect, characteristic changes in the chemical shift occur.
The proton magnetic resonance of chloroform was measured
in various sterically hindered amines. The PMR signal varies
according to R within a range of 90 cps at 60 Mc. The
resonance frequencies bear a characteristic relationship to the
E, parameters of TUB [I], which give a measure of the steric
requirements of alkyl groups (see Table). A linear correlation is obtained which is simple to apply in order to determine steric parameters by proton magnetic resonance.
[Z 9/835 IE]
Received: June 2!st, 1965
German version: Angew. Chem. 77, 720 (1965)
[ l ] Oligomers and Pleionomers, Part 42. - Part 41: H. Zahn,
H . StoIper, and G . Heidemann, Chem. Ber., in the press.
[21 The following abbreviations are used:
Seb = -CO(CH~)8COCap = -NH(CH2)5COB
= -NH(CH2)6NHUnd
-NH(CH2)loCO= -CO(CH&CODod = -NH(CHZ)iiCO-.
A
[31 H. Zahn and G. B. Gleitsmann, Angew. Chem. 75,772 (1963);
Angew. Chem. internat. Edit. 2,410 (1963).
[4] M. Rofhe, 3. Polymer Sci. 30, 227 (1958).
[Sj P. Kusche, Doctorate Dissertation, Technische Hochschule
Aachen, 1963.
[6] G. B. Gleitsmann, Doctorate Dissertation, Technische Hochschule Aachen, 1962.
Investigation of Steric Features
by Proton Magnetic Resonance
By Dr. H. J. Friedrich
Table 1. Relationship between the chemical shift 6 of the PMR signal of
CHCI3 in amines and the Es parameters of Tuft [!I. The measurements
were made with approx. 0.5 % solutions of CHCI3 at 20 "C with
tetramethylsilane as internal standard in a Varian A 60 instrument.
RlRzRJN
gES
G[cpsat
60 Mc/s
R3
H
H
H
H
H
CH3
CzHs
H
H
CzHs
n-C3H7
n-C4H$
n-C4H9
i-C4H9
[a1 6 w 430 cps for CHCI, in indifferent solvents such as hexane.
Chemisches Institut der Universitat Wiirzburg (Germany)
Chloroform exhibits only a single proton magnetic resonance
signal in basic solvents owing to the formation of hydrogen
bonds with rapid proton exchange; the chemical shift ob-
Received: June 24th, 1965
IZ lZ/S3S IEl
German version: Angew. Chem. 77, 721 (1965)
[l] R . W . Tuft, J. Amer. chem. SOC.74, 3120 (1952).
CONFERENCE REPORTS
Meeting of South-West German Chemistry Lecturers
The meeting took place in Mainz (Germany) from April 28th
to 30th. Altogether 110 papers were presented, in part in
three parallel sessions. In order to avoid repetition of
publication, only those lectures will be summarized the
contents of which have not yet been published or submitted
for publication. The abstracts are arranged alphabetically
according to authors. For a subject index, see page 727 of
this issue.
I
The Polymerization of Isoprene Initiated by
Organolithiwn Compounds
isoprene are rate-determining. Solvation by ether reduces the
reactivity of the initiator. The overall reaction rate in ether
is therefore higher or lower than in heptane, depending on
the concentration [l] (double-dilatometer technique in the
range of low concentrations).
On the basis of the kinetic data and a postulated reaction
mechanism, a system of differential equations and equilibrium
relations was set up and solved numerically with an analogue
computer. The calculated conversion-time curves agreed up
to 90% conversion with the experimental curves within
the computing error of 1-3 %.
F. Bandermann and H. Sinn, Munchen (Germany)
Solutions of butyl-lithium in n-heptane were found to have
the resistances tabulated below (cell constant = 0.01 cm-1):
At initiator concentrations above 10-5 molejl in n-heptane,
ether, or mixtures of both, the concentrations of the undissociated monomeric organolithium compound and of the
[I] Cf. H . Sinn and F. Patat, Angew. Chem. 75, 805 (1963); Angew. Chern. internat. Edit. 3, 93 (1964); Fig. 1.
Angew. Chem. internat. Edit. 1 Vol. 4(1965)
1 No. 8
697
Документ
Категория
Без категории
Просмотров
0
Размер файла
235 Кб
Теги
isolation, polyamide, cyclooligoamides, higher
1/--страниц
Пожаловаться на содержимое документа