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N-Acyl-N-arylsulfonyldiazenes; Detection and Use in the Synthesis of Amides.

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then treated with petroleum ether. This affords 0.26g (32 %)
( 5 a ) , m.p. 293-294°C. 0.31 g (38%) ( 3 a ) can be obtained
from the petroleum ether solution by distillation.
Received: July 4. 1977 [Z 789 IE]
German version: Angew. Chem. 89, 742 (1977)
CAS Registry numbers:
( 1 u), 40168-06-7; (1 b ) , 63588-82-9; ( 2 a ) . 63588-83-0; (Zb), 63588-84-1;
( 3 a ) , 4686-14-0; ( 5 a), 60538-88-7; AgCN, 506-64-9
G. Hojle, B. Lunge. Angew. Chem. 89, 272 (1977); Angew. Chem. Int.
Ed. Engl. 16, 262 (1977).
Bruker W H 270 at 67.88 MHz in CDCI, at 30°C; 13C enrichment in
theisocyanidegroup90%,; halfwidthofsignal l 0 H z a t 6 = 169.3. Oncooling, a coalescence of this signal a t ca. - 10°C is followed at - 50°C by its
replacement by two new signals of comparable intensity at 6=146.3
and 157.2, which can be assigned t o the E- and Z-isomers. Unusual,
however, is that both signals are shifted t o higher field. The possibility
that we observed the dimer ( 4 a ) , likely to be present in the equilibrium,
is ruled out by the low-temperature IR spectrum.
This thermolability casts doubt upon the isolation [4] of N-alkylformimidoyl isocyanides in admixture with the corresponding cyanides. The IR
and "C-NMR data [4] (2120 cm-' and Sac= 157.7, resp.) suggest that
these compounds are actually alkyl isocyanides originating from basecatalyzed H C N elimination from the N-alkylformimidoyl cyanides.
J . H . Boyer, J . Kooi, J. Chem. SOC.Perkin I. 1975, 1743; J . H. Boyer,
J . Dunn, J . Kooi, J . Am. Chem. SOC.98, 1099 (1976).
A cyanide-catalyzed dimerization of ( 2 a ) by way of a 2-phenylquinazoline can be ruled out since added 2-(m-tolyl)quinazoline i s neither
consumed nor incorporated in ( Z a ) .
[l]
[2]
[3]
[4]
[S]
N-Acyl-N-arylsulfonyldiazenes ; Detection and Use in
the Synthesis of Amides
By Hansjurgen Golz, Bernd Glatz, Georges Haas, Gunter
Helmchen, and Hans Muxfeldt (deceased)[*]
While N,N'-diacyldiazenes are in many cases stable and
readily accessible, to our knowledge the N,N'-disulfonyl- and
N-acyl-N'-sulfonyldiazenes (excepting azobissulfates) have so
far not been reported'']. Owing to the pronounced nucleofugal
character of the sulfonylazo group['] these compounds ought
to represent an interesting new class of acylating agents.
We have now been able to demonstrate the existence of
a compound of type ( 2 ) , uiz. N-benzoyl-N'-tosyldiazene ( 2 a )
(cf. Scheme 1 and Table 1). Oxidation of the hydrazide ( I a )
with lead tetraacetate in the presence of cyclopentadiene at
-78°C leads to formation of the cycloadduct (3)[31in 33 %
yield, and on addition of boron trifluoride ether in 53%
yieldr41(cf. experimental procedure). In order to estimate the
lifetime of ( 2 a ) the temperature and the interval of time
between completion of oxidation and addition of cyclopentadiene were varied. Oxidation at - 50°C and addition of cyclopentadiene after 30 minutes leads to 40 % (3), whereas oxidation at -30°C and addition of cyclopentadiene after 10
minutes leads to only traces of (3). Consequently, at temperatures below ca. -50°C ( 2 a ) is sufficiently stable for its isolation.
Table 1. Carboxamides ( 4 ) and sulfinamides ( 6 ) prepared (see experimental)
from hydrazides ( I ) and benzylamine (R3=CH2C6H5)by oxidation with
lead tetraacetate.
Reactant
R'
R'
T
["CI
Products
yield [ %]
-60
( 4 a ) >98
25
-60
25
-80
(4a)
-50
25
-60
25
(4b)
(46)
(4c)
(412)
(4c)
(4c)
(4c)
75
77
51
>98
89
28
92
9
-
5
(6a)
(6b) 2
(66) 12
~
(6b) 9
( 6 6 ) 42
(6c) 5
( 6 c ) 76
N-Acyl-N'-arylsulfonyldiazenes (2) can acylate amines.
Thus, oxidation of the hydrazides ( I a)-( 1 e ) with lead tetraacetate in the presence of benzylamine below -60°C leads
to the carboxamides (4)15] in good yields, together with small
amounts of the sulfinamides (6) (cf. Table 1 and experimental
procedure). The amount of ( 6 ) can reach significant proportions if the reaction is carried out at room temperature. It
follows from our present studies and from numerous other
data[61that the ratio ( 6 ) / ( 4 ) increases with increasing temperature and increasing bulkiness of R' and R2.Electronic effects
have comparatively little influence in this respectL6?
The results can be interpreted in terms of Scheme 1. The
diazenes ( 2 ) stable at -60°C react cleanly with amines to
give carboxamides; however, at higher temperatures competing elimination of nitrogen leads to the mixed anhydrides
( 5 ) . These are preferentially attacked at the sulfur atom by
arnines1'1. This is confirmed by predominant formation of
the sulfinamide ( 6 e ) from ( I e ) at room temperature; in
this instance the situation is especially sterically unfavorable
for attack at the sulfur atom.
Experimental
[**I
2-Benzoyl-3-tos~l-2,3-diaza-S-norbornene
(3): A solution of
lead tetraacetate (4.0 mmol) in dichloromethane (25 ml) is
added dropwise during I h at -78°C to a solution of ( 1 a )
(880mg, 3.03 mmol),cyclopentadiene(30.3mmol), and boron trifluorideether(1.54mmol)in THF/acetonitrile (1/1)(SO ml). After
a further 4 h at -78°C the solution is allowed to warm over
a period of ca. 20 h to room temperature. The crude product
obtained after treatment with ether, extraction with sodium
hydrogen carbonate solution, drying (sodium sulfate) and
removal of organic phase by evaporation is chromatographed
on 300g silica gel (chloroform/acetone 95/5, 15 ml fractions).
Fractions 64 to 80 yielded 564mg (53 %) ( 3 ) , colorless crystals,
m. p. 148-1 49 "C, after recrystallization from ethyl acetate/
hexane.
Carboxamides ( 4 ) : A solution of lead tetraacetate (1 mmol)
in dichloromethane (10ml) is added dropwise during 20min
to a solution of hydrazide ( I ) (1 mmol) and benzylamine
(Smmol) in T H F (for temperature see Table 1). After 2 h
728
Angew. Chem. Jnt. Ed. Engl. 16 (1977) N o . 10
[*] Dr. H. Golz, Dr. B. Glatz, Dr. G. Helmchen ['I, Prof. Dr. H. Muxfeldt
['I
(deceased)
Institut fur Organische Chemie, Biochemie und lsotopenforschung der
Universitat
Pfaffenwaldring 55, D-7000 Stuttgart 80 (Germany)
Dr. G. Haas ["'I
Ciba-Geigy AG
CH-4000 Basel (Switzerland)
Author to whom correspondence should be addressed
Formerly at Cornell University, Ithaca, N. Y.
at the same temperature the reaction mixture is treated with
ether and extracted with 1 N hydrochloric acid, 1 N sodium
hydroxide, and water. The crude product obtained after drying
and evaporation of the ether phase is recrystallized or chromatographed on silica gel for determination of the ( 4 ) / ( 6 )
ratio.
at 11O0C/1O~'mbar. It crystallizes in at least two forms
[triclinic Pi, a=9.096(2), b= 9.1 32(2), c = 8.878(3)A,
a= 100.22(2),8=99.96(3), y = 115.41(2)",Z = 1; rhombohedral,
a=10.524(2)A, a=50.09(2)", Z=1], but in each case in a
pure molecular lattice.
Received: July 12, 1977 [Z 788 IE]
German version: Angew. Chem. 89.742 (1977)
CAS Registry numbers:
( l a ) , 3064-19-5; ( I b ) . 6631-28-3; ( l e i , 4837-35-8; ( I d ) , 10565-50-1; ( l e ) ,
63548-95-8; ( 2 a ) , 63548-96-9; ( 2 b ) , 63548-97-0; (Zc), 63548-98-1 ; (ZdJ,
63548-99-2; ( 2 e ) ,63549-00-8; ( 3 ) , 63549-01-9; ( 4 u ) . 1485-70-7; ( 4 b ) , 588-465 ; ( 4 c ) . 26209-45-0; ( 6 u ) , 6829-91-0; (66). 6873-90-1: ( 6 c ) , 63549-02-0;
cyclopentadiene, 542-92-7; benzylamine, 100-46-9
F
____
[l]
[2]
[3]
[4]
[5]
161
[7]
Reviews: H. Bock. Angew. Chem. 77, 469 (1965); Angew. Chem. Int.
Ed. Engl. 4, 457 (1965); S. Patui: The Chemistry of the Hydrazo, Azo
and Azoxy Groups. Wiley, New York 1975, Parts I and 11.
W R . Bumford, T: S. Sterens, J. Chem. Soc. 1952, 4735.
All the isolated compounds described here were unequivocally characterized by elemental analysis and spectroscopy ('H-NMR, IR. MS).
Attempts to trap N.N'-ditosyldiazene, possibly formed analogously from
N,N'-ditosylhydrazine by oxidation at -75"C, with cyclopentadiene,
were unsuccessful; cf. [6].
Carboxamides are prepared by oxidation of acylhydrazines and N-acylN'-phenylhydrazines: Y Wolman, P . M . Gullop, A. Putrhornik, J. Am.
Chem. Soc. 83, 1263 (1961); H. B. M i h e , W Kildag, J. Org. Chem.
30, 64 (1965).
H. Gijfz, Dissertation, Universitat Stuttgart 1976.
The intermediate ( 5 a ) formed from sodium p-toluenesulfinate and benzoyl chloride in ethanol correspondingly yields chiefly ethyl p-toluenesulfinate; cf. M . Kobayushi, Bull. Chem. SOC.Jpn. 39, 967 (1966).
Fig. 1. Crystal structure of Te(OTeF&, triclinic modification. R =0.029.
It can be seen in Figure 1 how the large OTeF5 ligands
perfectly occlude the central atom, due to the TeOTe angle
of 138". The high melting point naturally arises from the
spherical shape of the molecule. Spatial compactness is much
better here than in the case of U(OTeF5)6[41,since in the
latter the U-0-Te angle reaches almost 280".
On the other hand, Te(OTeF5), ( 1 ) reacts with XeF2 and
with Fz to give a mixture of products.
cis-F2Te(OTeF&
By Dieter Lenrz, Hans Pritzkow, and Konrad Seppelt"]
The accidental discovery['] and subsequent elucidation of
the structure''] of t r u n ~ - F ~ T e ( O T e( F4 ~) motivated
)~
interest
in the directed synthesis of higher tellurium oxide fluorides
utilizing the oxidative action of xenon(I1) derivatives. It was
essential, in the first place, to establish the ultimate steric
accommodation of a tellurium atom and whether the octahedral construction remains valid. As will be demonstrated in
the present communication, the covalent chemistry of tellurium can be developed quite extensively.
First of all, Te(0Te5)4 ( I ) was synthesized (m.p. 89"C,
subl. 110"C/10-2 mbar, 99.5 % yield) and then oxidized with
Xe(OTeF5)z131to Te(0TeF5)6(2) (95 % yield).
3 TeF,
+
-
4 B(OTeF5)3
I / ) + Xe(OTeF5),
100°C
4 BF,
Xe
+
3 Te(OTeF5)4
(1)
+
Te(OTeF5),
(2)
(2) is the largest oxide fluoride of tellurium so far reported,
and, with respect to its mass, one of the heaviest of all inorganic
molecular compounds.
Compound (2) is a colorless solid having the extremely
high melting melting point of 242°C; nevertheless, despite
its high relative molecular mass of 1559.2 it can be sublimed
[*] Priv.-Doz. Dr. K . Seppelt, Dip].-Chem. D. Lentz, Dr. H. Pritzkow
Anorgamsch-chemisches Institut der Universitat
Im Neuenheimer Feld 270, D-6900 Heidelberg 1 (Germany)
This work was supported by the Deutsche Forschungsgemeinschart
and the Fonds der Chemischen lndustrie.
I"*]
Anyrw. Chem. 1nl.
Ed. Enyl. 16 (1977) No. 10
1
-
trans-F4Te(OTeF &
The Te-0-Fe System: T e ( 0 T e F 5 ) , [ * * l
200c
(I) + Fz
(3)
FTe(OTeF5)5 ( 5 )
(6)
cis-FzTe(OTeFd4
13)
rrans-F2Te(OTeF5),
(4)
FTe(OTeF5)s
(5)
The product cis-FzTe(OTeF5)4 (3) (m.p. - 12"C, b.p.
63"C/3 mbar) is shown by its "F spectrum to be the isomer
of the already known trans-compound ( 4 ) ; the spectrum
shows two different pairs of OTeFs groups (tjA=51.5,
6 ~=
r 51.6, 6 ~ ~ = 6 ~ > = 3 9 .It7 )is. still unclear why only the
cis isomer is formed in the reaction with XeF2, while fluorination with elemental fluorine also gives the truns isomer.
The fivefoldsubstituted compound FTe(OTeF5)s ( 5 ) occurs
as by-product (m.p. 4 8 T , b.p. 9O-1OO0C/5 mbar), and, as
expected, in the "F-NMR spectrum it shows different OTeFs
signals in the intensity ratio 1 : 4 (6~=48.0, 6d =48.1,
6~~= ~ R =L 36.9).
Finally, an old structural problem could be solved by directed synthesis:
TeF,
+
Xe(OTeF&
20 "c
Xe
+ ( rruns)F5TeO-TeF,-OTeF5 ( 6 )
+
( cis)F5TeO-TeF4
I
0
TeF5
17)
A compound FsTeOTeF40TeFs was first described as long
ago as 1956, but its structure was not elucidated[51. We
obtained a 3:2 mixture of cis/trans isomers, which owing to
their markedly different physical properties [ ( 6 ) : m.p. 1 9 T ,
b.p. 150°C; (7): m.p. -26"C, b.p. 127"C] could readily
729
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