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Experiments with Chloramine T in the Toluenesulfonylurea Series.

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analytical grade, containing 0.1-0.3 %, HzO; acetates treated
as above: solutions containing 0.2---0.9% H20; 25 f 0.2"C;
measurements made in a glove-box over PzOj [3]. The specific
conductivity of glacial acetic acid was 1.0~10-7-1.1 x 10-7,
of 0.1 M acetate solutions IxlO-5---2x IO--5 (NH4, Ba),
8.7~
10-6-7.7~ 10-6 (Sr, Mg, TI), l.IxlO-6--2.2x 10-6 (Ni,
Cd, Pb) and 0 . 9 ~1 0 7.~ 1.1 x 10-7 (Bi, Cu; 0.01 M) [mho/
cm]. The minimum equivalent conductivity occurs between
0.1 and 0.01 M and dccredses in the order NH4, TI; Ba, Sr,
Mg; Cd, Ni, Pb from 0.30 to 0.005, and for Cu and Bi to
< O.CO5 [mho-cm2!Val]. The dielectric constants of 0.1 M
solutions were from 7.3 to 8.2, and of 0.01 M solutions
from 6.5 t o 6.7. These figures are remarkably close to the dielectric constant of the solvent employed, i.e. from 6.4 to 6.5
(water-free 6.14).
Thus, the metal acetates are only weakly ionized in glacial
acetic acid. This, together with solvation differences [I b], is
a fundamental reason for the different, and unfortunately
often less quantitative nature of non-aqueous precipitations
in solvents of low dielectricity constant in comparison with
those in aqueous medium. Sometimes the precipitation of a
cation depends strongly on the nature of the anion, which
has the same cause.
From 5 to 120 mg of nitrate can be quantitatively determined
by conductometric titration in glacial acetic acid by precipitation with 0.5 N BaAc2.H20 as Ba(N03)2, and from 20 to
200 mg of sodium can be determined similarly by precipitation with 0.5 N H2S04 or (COOH)z2HzO. Ni2+ was
separated from Co2f by precipitation with SCN- as
Ni(SCN)z. Deep blue [Co(SCN)412- remains in solutions [41.
Received, March 18th, 1963
[Z 476/303 IE]
Publication withheld until now a t the author's request.
German version: Angew. Chem. 75,418 (1963).
cyclohexylguanidin (3). Wc have obtained (3), m.p. 122 to
124 O C , in 61 % yield from equivalent amounts of chloramine
T, p-toluenesulfonamide (4). and cyclohexylisonitrile in
aqueous acetone as solvent.
This course of reaction was unexpected i n view of the experiments of N e f [ l ] with alkyl isonitriles. It can be interpreted
that equivalent amounts of chlorarnine 1'and cyclohexylisonitrile react together first to f'orm (S), with subsequent addition of one mole of p-tolLieiiesulfonarnide.
The reactivity of N-(p-to1ucncsulfonyl)-N'-alkylcarbodiimide
[2] is understandable when it is compared with that of the isocyanates: p-toluenesulfonyl isocyanate is considerably more
reactive than cyclohexyl isocyanate, for instance.
Although it did prove possible to split off HCI from N-(ptoluenesu1fonyl)-N'-cyclohexy Ichloroformamidine by heating
it i n vucuo, the initial product formed, viz. (S), could not be
isolated, as it polymerized a1 once.
It was then obious to try allorations in the conditions of the
reaction between equivalenl amounts of chloramine T and
alkyl isonitriles in order to avoid interaction of the assumed
intermediate, N-(p-toluencsulfonyl) - N'-alkylcarbodiimide,
with the p-toluenesulfonamide which evidently appears as a
by-product.
Partial addition of water onto (5) was achieved by using great
dilutions in aqueous acetonc. However, the yields of (6), were
very low, and could not be increased, despite variations in the
experimental conditions.
[l] Separations in non-aqueous solution 111. [a] Part I, B. Sansoni, Angew. Chem. 66, 595 (1954); [b] Part 11, Z. Naturforschg.
I l b , 117 (1956).
[2] [a] B. Sansoni and W. N a s s , Graduation Thesis, Regensburg,
March, 1953; [b] Angew. Chcm. 66, 330 (1954); [c] K. Srarke
and A.T. Casey, M.S. Thesis, University of Vancouver, B.C.
(Canada), April 1953; H . Hardt, Lecture at Bonn (Germany)
1962; see Angew. Chem. 74,500 (1962).
[3] R . Sfolz, Ph. D. Thesis, Universitiit Marburg/Lahn, 1963.
[4] Sansoni, Arold, Murawski, and v. Elmer, unpublished
experiments, 1962/1963.
Experiments with Chloramine T in the
Toluenesulfonylurea Series
Reactions of Chloramine T with Alkyl Isonitriles
By Dr. W. Aumiiller
Farbwerke Hoechst AG., vormals Mcister Lucius & Briining
Frankfurt/Main (Germany)
However, chloramine T reacts smoothly and clearly with isonitriles if methanol or ethanol is used as solvent. The alcohol
adds on preferentially to Ihe assumed intermediate. With
cycloalkyl isonitriles, up to 65 %, N-(p-toluenesulfony1)-N'cycloa~kylisouredethers are obtained by elimination of NaCI.
Hydrolysis of these ethers gives N-(p-toluenesulfony1)-N'cycloalkylureas in nearly quantitative yield. Aliphatic isonitriles give lower yields of isourea ethers.
We propose the following tcntative course of reaction for the
formation of the N-(p-to1ucnsulfonyl)isourea ethers:
Dedicated to Professor D r . K. Winnucker on the occasion of
his 60th birthday
If chloramine T ( I ) is mixed with an isonitrile, e.g. cyclohexyl isocyanide (2), and thc mixture is warmed on a steambath in the presence of CaCO3, it soon decrepitates. The remarkable product formed is 1,2- bis(toluenesulfonyl)-3-
Received, June 4th, 1963
IZ 549/380 IEI
German version: Angew. Chem. 75, 857 (1963)
[ I ] I . U.Nef, Liebigs Ann. Chcni. 270,267 (1892); 280,291 (1894).
[2] To our knowledge, no representative of this type of compound
has yet been isolated.
61 6
Angew. Chem. iwtcrntrt. Edit.
Vol. 2 (1963) No. 10
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