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Detection of the Molecules W2Cl6 and W3Cl9 in the Gaseous State.

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0.44 g of N,N-dimethylformamide in 90 ml of toluene. After
removal of the excess of phosgene in a stream of nitrogen
and rectification, 4.35 g (65.4 %) of benzyl isocyanate, b.p.
8OoC/7 mm, is obtained. No isocyanate is formed in the
absence of catalyst under otherwise similar conditions.
[ Z 518 1El
Received: May 22nd, 1967
German version: Angew. Chem. 79, 651 (1967)
[*I Dr. H. Ulrich, B. Tucker, and Dr. A. A. R. Sayigh
The Upjohn Company, D. S. Gilmore Research Laboratories
North Haven, Conn. (U.S.A.)
[ l ] 0. Folin, Amer. chem. J. 19,323 (1897).
[2] H . Gross and J. Gloede, Chem. Ber. 96, 1387 (1963).
[3] T . Mukaiyama, T. Fumisawa, and 0 . Mitsunobo, Bull. chem.
SOC.(Japan) 35, 1104 (1962).
Preparation of Hexaazidophosphates
By H . W. R o e s k y [ * ]
similar conditions. The trichloride obtained is soluble in a
small amount of warm (CH3)2SO, giving a dark brown
solution. If this solution is treated with dilute aqueous HzS04
and Na2S04, only about 2.5/18 of the CI becomes titratable
with Ag2S04. More AgCl is precipitated only on warming,
and the W complex is thereby destroyed with precipitation of
elemental Ag. The firm binding of the halogen is characteristic Of the groups [ M ~ X Sand
] [M&12].
The structure of the trichloride was determined from
Guinier measurements (by comparison with the Pt6C112
structure). The material crystallizes i n the hexagonal rhombohedral form with a = 14.91 A, c = 8.45 A, cia = 0.568,
flrh = 9.05 A, a,h = 110.8 O , in the space group RZ--C;i. The
unit cell contains three formula units wScIl8 (X-ray density
5.33 g/cm3). According to detailed calculation of intensities
(trial-and-error procedure) the atoms have the following
positions [position 18(f)]: 18 W with x = 0.120; y = 0.016;
I = 0.140; 18 CII with x = 0.134; y = 0.018; z = -0.310;
18 CIII with x = 0.249; y = 0.151; z = 0; and 18 CIIII with
x = 0.268; y = 0.035; z = 0.310. The W parameters were
determined by comparison of intensities, the CI parameters
by consideration of bond distances. The structure contains
discrete molecules [ w & l ~ 2 ] c l ~which
are arranged in a
(distorted) body-centered cube. Interatomic distances are:
W-W = 2.92, W-Cli = 2.30, W-CP = 2.52, all CI-CI >
3.6 A.
Conversion of the grouping [M6X8] into [M&12] can occur
in single steps by changing positions of X. However, the
conversion [M6&]X4 -f [M&l2] is also possible if the halogen sphere and the Mg octahedron rotate in one step by
45 O relative to each other (see Figure).
We recently reported the preparation of the tetrachlorodicyanophosphate ion [PC14(CN)2]0111. We have now accomplished complete substitution at the phosphorus atom by the
more electronegative azide group and been able to prepare
the hexaazidophosphate ion [P(N&jIQ for the first time.
For the synthesis, sodium azide is added slowly, with vigorous stirring, to phosphorus pentachloride in anhydrous
acetonitrile (molar ratio PC15:NaN3 = 1:lo). The reaction is
slightly exothermic. Stirring is continued for 10 minutes at
room temperature and an excess of 5 % aqueous tetraphenylphosphonium chloride solution is then added dropwise. A
yellow viscous oil separates which can be reprecipitated from
acetone/water. 1 g of PCls gives 0.2 g of (C6H5)4PQ[P(N3)6]Q.
Tetraphenylarsonium chloride gives ( C & ~ ) ~ A S @ [ P ( N ~ ) ~ ] ~
under the same conditions. All operations are carried out
under a rapid current of dry nitrogen. The substances explode
violently on slight warming.
The purest samples are obtained by separating the oil immediately after its preparation and drying it over P4010 in a
vacuum desiccator. When moist, the compounds slowly
evolve N3H. The IR spectrum Of (C&5)4P[P(N3)6] in the NaCl
region shows strong bands at 2150,1250 with a shoulder, and
755 cm-1, which are ascribed to vas(N3), vs(N3), and v(P-N)
vibrations. Further strong bands at 560 and 585 cm-1 are
It is interesting that analogous “conversion” of the cationic
ascribed to deformation vibrations.
group does not occur when Br2 reacts with “tungsten dibromide” [W&r8]Br2Br4/2; in this case the system changes
[ Z 520 IE]
Received: May 18th, 1967
with formation of polybromide.
German version: Angew. Chem. 79, 651 (1967)
[*] Dr. H. W. Roesky
Anorganisch-Chemisches Institut der Universitat
Hospitalstr. 8-9
34 Gottingen (Germany)
[l] H . W . Roesky, Angew. Chem. 79, 316 (1967); Angew. Chem.
internat. Edit. 6, 363 (1967).
Tungsten Trichloride [w6cl&&
By R. Siepmann, H.-G. v. Schnering, and H. Schafer[*l
Compounds with the groups [M6X8] and [M6X12], where
X = halogen, are known for the heavy transition metals[ll.
When M = Mo or W the first type is regularly formed, and
when M = Nb, Ta, Pd, or Pt the second.
Two exceptions to this rule are now known: (i) the recently
discovered 121 iodide [Nb,&]I6/2 and (ii) the chloride
[w6c112]c16, which is described below.
31 reacts with liquid
Tungsten dichloride w&l8]C12c14/2
chlorine at ca. lOO”C, forming a black substance that contains 3 chlorine atoms per tungsten atom and gives sharp
X-ray diagrams. The wc16 formed simultaneously is extracted
with liquid chlorine at cn. 40 ‘C. Structural elements of the
starting material apparently withstand this vigorous reaction
with Clz. WC14 is converted completely into WClS under
Angew. Chem. internat. Edit.
/ Vol. 6 (1967) No. 7
[ Z 522 IE]
Received: May 16th, 1967
German version: Angew. Chem. 79, 650 (1967)
[*I DipLChem. R. Siepmann, Prof. Dr. H.-G. v. Schnering,
and Prof. Dr. H. Schlfer
Anorganisch-Chemisches Institut der Universitat
Hindenburgplatz 55
44 Munster (Germany)
[l] H. Schafer and H.-G. v. Schnering, Angew. Chem. 76, 833
[2] a) H. Schafer, H.-G. v. Schnering, A . Simon, D . Giegling,
D. Bauer, R . Siepmann, and B. Spreckelmeyer, J. Less-Common
Metals 10, 154 (1966); b) L. R . Bateman, J. F. BIount, and L. F.
Dahl, J. Amer. chem. SOC.88, 1082 (1966); c) A . Simon, H.-G. v.
Schnering, and H . Schiifer, Z. anorg. allg. Chem., in press.
[3] H. Schafer, H.-G. v. Schnering, J . Tillack, F. Kuhnen, H. Wohrle, and H. Baumann, Z. anorg. allg. Chem., in press.
Detection of the Molecules W2C16and
W,CI, in the Gaseous State
By K . Rinke and H. Schafer[*l
The solid lower tungsten halides are of particular interest
because of the formation of W-W bonds 11.21. These bonds
are probably essential also for the stability of the molecules
W2Ck and W3C19 that have now been observed in the mass
The Table shows the compounds studied and the relative ion
intensities observed (a dash denotes not observed). Isotopic
distribution was taken into account.The smaller fragmentsare
not given for electron energies of 50 eV; for 12 and 15.5 eV
the Table contains, however, all the WxCl$ ions’-observed.
( “C)
< 150
< 150
Relative ion intensities
% of
The products ofhydrolysis W02C12and WOCI3 occurred in the
mass spectrum as well as the chlorides, but the results are not
invalidated thereby.
The substances were placed in graphite crucibles (WC15 in a
glass capillary) and heated in the ion-source of the mass
spectrometer (CH 4 from Fried. Krupp,‘ MAT, Bremen). The
measuring range of the apparatus was up to mass number
1350. The ions recorded were identified by their mass numbers and isotopic distribution. Even the W3CP ion group
with its low intensity could be resolved (Fig. 1).
Fig. 1.
Ial WC13.4 is a material, amorphous to X-rays, containing 61
R . Sirpmann (21.
dimer is obviously considerably more stable against thermal
decomposition to monomers than is, e.g., A12C16 or FezC16.
Further, all the chlorine-deficient fragment ions, such as
w2cI’ to WzCI; and w3cI; to W3cli, observed to be formed
from w2C16 and W,CI; at 50 eV gave considerably lower
intensities than did the corresponding parent ions W2Cl2 and
W3Cl;. In this respect w2ci6 and W3C19 are comparable with
W,CIi ion group. Ordinate: Ion current.
Only the ions WCI;, WCl& W,C1+6, and W3Cl; observed at
low electron energies (ca. 12 eV) are to be considered as
primary ionized gas molecules. All‘the other ions are fragments of the evaporated parent molecules. This follows from
a study of the measured appearance potentials when WC14
was heated (reference value: ionization energy of argon
15.8 eV): WCl: 9.1 eV, WCl: 8.0 eV, WCI: 11.8 eV, W2Cl;
9.5 eV, W2Cli 11.9 eV, W3C1; 9.3 eV.
and 39.8% of C1, obtained by
the halides Re3C19 14~51,Re3Brg 15761,Tc3C19 (61, and Cu3C13[TI.
Experiments with MoCl5, MoC14, MoC13, and MobC112 gave
no indication of the occurrence of polymeric molecules in
the gas phasersl.
Received: May 16th, 1967
12 523 IE]
German version: Angew. Chem. 79,650 (1967)
[*I Dr. K. Rinke and Prof. Dr. H. Schafer
Anorganisch-Chemisches Institut der Universitat
Hindenburgplatz 55
44 Miinster (Germany)
[l] H. Schaifer and H.-G. v. Schnering, Angew. Chem. 76, 833
[2] R . Siepmann, H.-G. v. Schnering, and H . Schafer, Angew.
Chem. 79,650 (1967); Angew. Chem. internat. Edit. 6,637(1967).
[ 3 ] S. A . Shchukarev, G . I . Novikov, I. V. Vasil‘kova, A . V .
Suvorov, B. N . Sharupin, and A . K . Baev, Russ. J. inorg. Chem. 5,
802 (1960); cf. also S. A. Shchukarev, G . I. Novikov, and N . V.
Andreeva, Vestnik Leningradskoyo Univ. 14, No. 4, Ser. Fiz.
Chim. No. I, 120 (1959); Chem. Abstr. 53, 14619 (1959).
[4] K. Rinke and H . Schafer, Angew. Chem. 77, 131 (1965);
Angew. Chem. internat. Edit. 4, 148 (1965).
[ 5 ] A. Biichier, P . E. Blackburn, and J. L. Stauger, J. physic.
Chem. 70, 685 (1966).
[6] K. Rinke, M. Klein, and H . Schafer, J. Less-Common Metals,
in press.
[7] H . M . Rosenstock, J. R. Sites, J. R. Walton, and R . Baldock,
J. chem. Physics 23, 2242 (1955), and our own observations with
Cu3C13 and Cu3Br3.
[8] We thank Mr. H . Rabeneck for his help.
Conclusions :
WCl5 sublimes without decomposition (Experiment 2).
W2Cll0 was not observed although dimers were assumed
from measurements of equilibria [31 (disputable; cf. reaction
WC14 decomposes to some extent o n volatilization (Experiments 3 and 4). Disproportionation leads to the molecules
WCIs, W2C16, and some W3C19.
give the same
In the communication “Synthesis and Template Properties of
Deoxyoligonucleotides with Repeating Triplet Sequences”
by F. Cramer, W. Frolke, and H. Matzura, Volume 6 ,
June 1967, the following correction should be made.
It is important that the monomeric WC13 does not occur
alongside the considerable concentrations of w2c16. The
On page 562, right-hand column, line 30, “0.05 Mole of
each trinucleotide” should read “0.50 mmole of each trinucleotide”.
The other compounds (Experiments 5-11)
gaseous products as does WC14.
Angew. Chem. internat. Edit. / VoI. 6 (1967) 1 No. 7
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detection, gaseous, molecules, state, w3cl9, w2cl6
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