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New Hydrazyls of Low Molecular Weight and Polymeric Hydrazyls.

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ment of the coordinates by the method of least squares the R
value fell to 16.8%. Then the ideal positions of the nine
independent hydrogen atoms of the fourteen-membered ring
were calculated and these were included in the subsequent
calculations. In two further cycles of refinement, using isotropic temperature factors, the R value was lowered from
15.6 t o 14.9 %. The positions of the hydrogen atoms of the
methyl groups have not yet been found. Figure 1 shows the
projection of the nolecule o n the x,y plane, with the calculated atomic distances and bond angles. The standard deviations of these values are somewhat less than 0.01 A and
0.5', respectively.
Y
zines (3n)-(3d) can be oxidized by active PbOz to the liydrazyls, but these could not be isolated in solid form because they
have, in general, a strong dehydrogenating action on the
solvent.
Ri
(3)
j
Cpd.
Tt
C1
CI
C1
Br
F
CI
Fig. 1 . x,y Projection of a molecule of 1,2,8,9-tetraaza-l,8-~yclodecadien-3,lO-ylene diacetate ( I ) , with atomic distances and bond angles.
Numbering of the atoms is shown in circles for one half of the molecule,
and the heights (in 1/10 A) above the plane of projection are shown in
circles in the other half. The C-N bonds lie approximately in the direction of projection.
Each of the two sets of five carbon atoms (CI-C5) in the
fourteen-membered ring forms a stretched zigzag chain
(mean C-C distance 1.52A), these chains being joined by
the two trans-azo groups (distances: C-N = 1.47; N = N =
1.22A). The acetoxy groups are approximately perpendicular to the plane of the ring with the carbonyl-oxygen
atom approaching the azo group (separation: 0*...N2 =
3.26 A). The separations and angles are all normal, except
for the short C--0 bond in the acetoxy group (1.34A instead of 1.40A for a single bond C(sp2)-O).The"hole"inthe
ring is completely filled by two hydrogen atoms (on C3 and
C3').
Received: September 18, 1968
[ Z 877b IEI
German version: Angew. Chem. 80, I001 (1968)
( 3 ) . name
2,Z-Diphenyl-l[a-(4-biphenylyl)benzhydrazyllhydrazine
2,Z-Diphenyl-l[.*,a-bis(4-biphenylyl!
benzyllhydrazine
9-[(Triphenylmethyl)aminolcarbazole
9-[(Pentaphenylcyclopentadieny1)aminoIcarbazole
:9-[(2,4,6-Tricyanophen yl)ammo]carbazole
Dodecahydro-9(picrylamino)carbazole
13).
M.p. ( " C )
85-86
124- 126
239-241
-
3.5 h
7
3.5 h
7
2.5 h
3
218-219
45 min
3
157-1 59
-
-
161 - 162
3.5 h
8
[a] Half-life determined by ESR measurements in benzene solution.
Dodecahydro-9-(picrylamino)carbazole (3f) was also prepared, as model substance. It could be oxidized by active
PbOz to a relatively unstable radical.
R'
R2
(4a), R~ = R~ = H
H, R2 = C6H5
(4b), R'
(4c), R1 = R2 = C6H5
['I Dr. R. Allmann and Dr. I. Kawada
Mineralogisches Institut der Universitiit
355 Marburg, Deutschhausstr. 10 (Germany)
[ l ] S. Hiinig and J. Crumer, Angew. Chem.80, 1000 (1968); Angew. Chern. internat. Edit. 7, 944 (1968).
121 J . Knrle and I. L . Kurle, Acta crystallogr. 21, 849 (1966).
New Hydrazyls of Low Molecular Weight and
Polymeric Hydrazylst * *I
By D . Bruun and G. Peschkc*I
Almost all the stable hydrazyls known so far contain nitro
groupsrll; the use of hydrazyls as radical traps in kinetic
studies of polymerizations thus lead to uncontrollable side reactions. The only hydrazyl free from nitro groups known
hitherto
was 2,2-diphenyl-1-[2,4,6-tris(methoxycarbonyl
phenyl]hydrazyl[21[ ***I. We have now prepared the hydrazines (3a)- ( 3 e ) , which contain n o nitro group, by reaction
of a hydrazine derivative i f ) with a halogen compound (2)
in the molar ratio 2:l in ether or tetrahydrofuran. The hydraAngew. Chern. internor. Edit. / Vul. 7 (1968) / N o . 12
The polyhydrazines (4a)-(4c) and ( 5 ) were obtained by
treating diaryl(polyviny1phenyl)methyl chlorides 131 or tetraphenyl(polyvinylpheny1)cyclopentadienyl chloridet41 in tetrahydrofuran with 1,l-diphenylhydrazine (molar ratio 1 :2
calculated o n the chlorine content of the polymers). These
products can be oxidized in benzene solution by active PbO2
to polyhydrazyls that can be precipitated by dry light petroleum. The yellow-brown polymeric hydrazyls are stable in
the solid state and are paramagnetic. They are soluble in
benzene and tetrahydrofuran.
(3d) :
N-[ (Pentaphenylcyclopentndienyl)~rminolc~irbnzoIe
N-Aminocarbazole (18.4g. 0.1 mole) and pentaphenylcyclopentadienyl bromide[sl (26 g, 0.05 mole) in absolute tetrahydrofuran (ca. 150 ml) are refluxed gently for 5 h. The mixture is allowed to cool and precipitated hydrobromide is
filtered off. The solution is concentrated and the substance
remaining is dissolved in hot benzene and treated with a n
equal volume of hot ethanol, whereupon the hydrazine
gradually crystallizes out. Pale yellow crystals [m.p. 218 to
219°C. yield 25 -27 g (80- 8 5 7 3 1 are obtained after two recrystallizations.
945
To form the radical by oxidation, the substance is shaken
with a ten-fold excess of active PbO;! in benzene for 10 min.
On rapid removal of the solvent, the reddish-brown solution
affords an impure, reddish-brown paramagnetic product.
Received: September 30, 1968
[Z 880 IE]
German version: Angew. Chem. 80, 1002 (1968)
[*] Prof. Dr. D. Braun and Dip1.-Ing. G. Peschk
Deutsches Kunststoff-Institut
61 Darmstadt, Schlossgartenstrasse 6 R (Germany)
[**I These investigations were supported by the Deutsche Forschungsgemeinschaft.
[l] Review of the most important hydrazyls prepared up to
1964: Landolt-Bornstein, New Series, Group 11, Vol. 1, p. 45.
[***I The preparation of a,cc-diphenyl-2,4,6-tricyanophenyl
hydrazyl has recently been reported [J. Brefschneider and
K . Wallenfels, Tetrahedron 24, 1063 (1968)j.
[2] D. Braun, G. Peschk, and E. Hechler, Chimia 21, 536 (1967).
[3] D. Braun and R. J . Faust, Angew. Chem. 78, 905 (1966);
Angew. Chem. internat. Edit. 5, 838 (1966).
[4] D. Braun, R. J . Fausr, and G. Peschk, unpublished work.
[5] K . Ziegler and B . Schnell, Liebigs A n n . Chem. 445,266 (1925).
water separator (separating liquid: cyclohexanonejforniic
acid 30:l). The reaction mixture is allowed to cool and a
3-5-fold amount of methanol is added, whereupon white
( 3 g / crystallizes out after a few minutes; compound ( 3 g j
can be recrystallized from n-butanol.
Received: September 30, 1968
I2 881 IE]
German version: Angew. Chem. 80, 1002 (1968)
[*] Prof. Dr. H. J . Roth, H. George, F. Assadi, and
Dr. H . J. Rimek
Pharmazeutisches lnstitut der Universitiit Bonn
53 Bonn, Kreuzbergweg 26 (Germany)
[l] H . J. Roth, E. Schumann, H . George, and F. Assadi, Tetrahedron Letters 1968, 3433.
121 R. W. L. Clarke and A . Lapworth, J. chern. SOC.(London) 91,
704 (1907).
[3] A . Treibs and R. Derrn, Liebigs Ann. Chem. 589, 176 (1954).
[4] N . Dilthey, G. Hurting, and H . Passing, J. prakt. Chem. 156,
36 (1940); R. Kuhn and H. Raiser, Chem. Ber. 85, 498 (1952).
Pb(H2P04),.(C6H5),P0,
Lead(1v)
Tetrakis(dihydr0genphosphate)
Stabilized by Triphenylphosphine Oxide
Simple Synthesis of Substituted
1,2,3-Triphenylpyrroles
By F. Hiiber and M. S . A . El-Meligy[*I
By H . J . Roth, H. George, F. Assadi, and H. J . Rimek[*I
As simple as possible a synthesis of substituted 1,2,3-triphenylpyrroles was required in order that they might be
precisely characterized when obtained photochemically [ll.
For this purpose, benzoin was condensed with aniline under
catalysis by traces of formic acid, yielding 2-anilino-2-phenylacetophenone (anilinodeoxybenzoin) ( I j in almost quantitative yield. This was converted by reaction with CH-acidic
It
H
I
(3) C6H5
I
I
!
Acetophenone
Phenylacetaldehyde
Propiophenone
Phenylacetone
w-lhenylacetophenone
Cyclopentanone
Cyclohexanone
Cycloheptanone
Cyclooctanone
I-Tetralone
2-Tetralone
I-Indanone
i
Yielc
M.P.
( "C)
( %)
-
!
H
CH3
-(CH2)3--(CH2)4-(CHZ)S-(cHZ)6- o-C6H4-(CH2)2--o-(CHZ)~-C~H~-O-C6Ha- C H2-
70
75
25
45
20
30
53
35
24
35
28
31
196
175
181
195S197
277
188
174
158-160
144-148
208-210
209-210
193-195
carbonyl compounds (2) into the pyrrole derivatives ( 3 ) in
acceptable t o good yields. The pyrroles (3aj 121. (361 131, and
(3c) 141 have the properties recorded in the literature.
1,2,3-Triphenyl-4,5,6,7-tetrnhydroindole
(3g ):
2-Anilino-2-phenylacetone ( I ) (4 g ) is refluxed with cyclohexanone (4 g) and 85 "/, formic acid (200 g) for 3 h i n a
946
Binary lead(rv) phosphates have been hitherto unknown. In
our experience earlier attempts to prepare such compounds
failed because of insufficient knowledge of conditions and
gave only indefinite products with a considerable Pb(I1) content 111 or complex lead(1v) phosphate(v) compounds 121 (the
possible occurrence of complex phosphorus-containing
lead(1v) derivatives had already been considered by Bode and
VossI3I). Our attempts t o obtain lead(1v) phosphates by
treatment of Pb(OCOCH3)4 or PbOz with phosphoric acid
of various concentrations led finally t o phosphatolead(1v)
acids, e.g., Hz[Pb(HzP04)6], in which the central atom
achieves the minimum coordination number 6 (41.
We then tried to stabilize lead(1v) phosphates by neutral
electron-donors, such a s (C6H5)3PO. in two ways, namely,
first by trapping binary lead(rv) phosphates by simultaneous
complex formation with the donor at the moment of their
formation in the above-mentioned reactions and, secondly,
by anion-exchange of lead(1v) coordination compounds. We
had no success with the first method, because complex formation with H3P04 to very stable lead(~v)acids (formally
H2[PbX4(HzP04)2]) associated vin hydrogen bridges occurred
immediately o n dissolution of lead(rv) compounds in phosphoric acid and ligand exchange then occurred only subsequently in a slow reaction. The second method, however,
was successful:
When Pb(OCOCH3)4 (11.1 g) was added to a solution of
( C ~ H S ) ~ P(1O3 g) in anhydrous benzene (100 ml), a yellow
precipitate was at once formed, which was slowly decolorized
on addition of anhydrous phosphoric acid (9.3 g). After 3
hours' stirring at 50 "C the precipitate was filtered off under
reduced pressure and dried. Elemental analysis accorded
with the composition Pb(H*P04)4. (C,jH5)3PO (oxidation
value 99%).
This white crystalline product, which is slightly soluble in
methanol but insoluble in other solvents, is astonishingly insensitive t o moisture and is hydrolyzed only slowly in cold
water although rapidly in hot water with separation of PbO?;
it decomposes in a vacuum above 140 "C. It was found thermogravimetrically that (CsH&PO is first split off quantitatively, and that the donor-free residue, presumably Pb(HzP04)4,
then at once decomposes forming lead(1r) phosphate.
The behavior on decomposition shows the importance of the
donor for stabilization of the oxidation state + 4 of the central
atom; immediately after removal of the (CsH5)3PO the change
of oxidation state Pblv + Pb" occurs with loss of oxygen.
The yellow precipitate that is formed on addition of
Angew. Chem. internat. Edit.
/ Vol. 7 (1968) No.
12
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