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Dicyanononasulfane S9(CN)2ЧAn Unbranched Chain of Thirteen Atoms.

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Ga-X distances, and by an estimation of the valency of X
according to Donnay and Allmann.r'3*141
With the exception of F 1 and its symmetry equivalent atoms, the 0 and F
atoms are p3-bridging. F 1 is pseudo p3-bridging. Two of the
Ga-F distances are short (Ga 1-F 1 197.3(3) pin, Ga2-F 1
222.3(2) pm); the remaining weaker Ga-F contact of
252.1(3) pm is between Ga 1 and F 1 B. The solvent molecules in 1 . T H F and 2.THF are not coordinated to the
metal atoms. The linking of the six Ga atoms through F
and 0 atoms causes an approach of neighboring metal
atoms to 298.05(9) pm (Ga 1 . . . Ga2) and 319.6(1) pm
(Ga 1 . . . G a 2 B) ; some 70 pm shorter than the sum of their
van der Waal's radii (380 pm).[L51However, bonding
Ga-Ga interactions in 2 can be discounted.['61
Topologically related clusters can be found, for example,
in organotitanium oxides: [(MeC,H4),Ti,C1,04~,~'
[Cp,Ti,C1,0,],['71 and [Cp,Ti,0,]['81 all have the same construction principle as 2, regardless of the oxidation state of
the titanium. As the space-filling model shows, the central
gallium fluoride oxide unit is sterically shielded by the
mesityl ligands, and this explains the kinetic inertness of 2
towards attack by water.
On the basis of cryoscopic molar mass determinations in
benzene, and from NMR spectroscopic investigations, we
assume that 2 does not dissociate in THF or toluene (1311,
n = 1.03). The I9F NMR spectrum shows two signals at
6 = - 90.7 (three F) and -104.0 (one F). The 'H and I3C
NMR spectra support this conclusion; two sets of signals
were found, one for each of the groups of mesityl substituents in different environments, with an intensity ratio of
1:l.
Experimental Procedure
atomic positions of H atoms refined with common temperature factors (H
atoms of C 31 on the disordered THF molecule were not refined), numerical absorption correction ( ) I = 33.6 cm-'), R = 0.046, R, = 0.045. Enraf
Nonius CAD4 four-circle diffractometer, Cu,, radiation, graphite
monochromator. Further details of the crystal structure investigations
may be obtained from the Fachinformationszentrum Karlsruhe, Gesellschaft for wissenschaftlich-technische Information mbH, D-76344 Eggenstein-Leopoldshafen (FRG) on quoting the depository number CSD57903, the names of the authors, and the journal citation.
171 Overview of organogallium compounds in Orgunogu/lrurn Compounds,
Gmelin, Handbook of Inorganic Chemistry, Gullium. Part 1, Springer,
Berlin, 1987.
[81 M. 5. Power, J. W. Ziller, A. R. Barron, Organometallrcs 1992, I 1, 2783.
191 D. A. Atwood, A. H. Cowley, P. R. Harris, R. A. Jones. S . U. Koschmieder, C. M. Nunn, J. L. Atwood, S. G. Bott, Orgunomerulircs 1993, 12, 24.
[lo] A. H. Cowley, R. A. Jones. P. R. Harris. D. A. Atwood. L. Contreras,
C. J. Burek, Angeir. Chem. 1991, 103, 1164; Angeir. Chem. Int. Ed. Engl.
1991. 30. 1142.
[ l l ] M. B. Power, A. R. Barron, J. Chem Soc. Chem. Commun. 1991. 1315.
1121 M. 5. Power, J. W. Ziller, A. N . Tyler, A. R. Barron, Organomelullics 1992,
11. 1055.
1131 G. Donnay, R. Alhmnn, Am. Mineral. 1970. 55, 1003; R. Allmann.
Monutsh. Chem. 1975. 106, 779.
1141 Examples for the use of the Donnay and Allmann relationship can be
found in: W Massa. D. Babel, Chem. Rev.. 1988. 88, 275.
[I51 J. E. Huheey. Anorgunischr Chemie, de Gruyter, Berlin, 1988.
[I61 P. Alemany, S. Alvarez, Inorg. Chem. 1992. 31,4266.
1171 A. Roth, C. Floriani, A. Chiesi-Villa,C. Guastini, J. Am. Chem. Sor. 1986,
108, 6823.
[18] C . J. Huffman, J. G. Stone, W C. Krussel, K. G. Caulton. .I. Am. Chem
Soc. 1977. 99. 5829.
Dicyanononasulfane S,(CN),-An
Chain of Thirteen Atoms**
By Ralf Steudel,* Klaus Bergemann, Jiirgen Buschmann,
and Peter Luger
1: Synthesis according to ref. [4]
2 : 0.54 g (1.65 mmol) of 1 was dissolved in a mixture of toluene (20 mL) and
THF (2 mL). H,O (0.02 mL. 1.10 mmol) were added. The solution was stirred
at room temperature for three hours and then allowed to stand. The product
2.THF separated from the solution in the form of colorless, rectangular prismatic crystals. Yield: 0.27 g (73% with respect to I ; scaled-up reactions give
corresponding yields). M.p. z 250 'C.
Cryoscopic molar mass determination (benzene, c = 0.0054 M): M , =1311,
n =1.03. 'H N M R (C,D,, TMS ext.): 6 = 2.09. 2.15 (s, 18H. C4-CH,). 2.51,
2.54 (s. 36H. C2/6-CH3), 6.60, 6.67 (s, 12H, C3/5-H); "C NMR (C6D6.TMS
ext.): 6 = 21.0, 21.2 (C4-CH3). 24.5, 24.8 (C2/6-CH3). 127.5. 127.7 (C3/5),
138.8, 139.0 (C4), 145.2, 145.4 (C2/6). 145.6. 145.7 ( C l ) ; "F NMR ([DJTHF.
CFCI, ext.): 6 = - 98.7 ( s , 3F). -104.0 (s, 1F). IR (Nujol): i [ c m - ' ]= 2728,
1600. 1558. 1495, 1412. 1292. 1238, 1030. 948. 849. 843. 688. 634,
590. 492. 437, 407, 293. EI-MS (70 eV): mi; (X)1238 (4) [(M-2Me+].
1142 (3) [(M-GaF,)'].
1041 (10) [(M-Mes-30-4Me)+],
925 (16)
[(Mes,Ga,F,O,-C,H,)+],
819 (7) [Mes,Ga,FO,)+], 207 (7) [(MesGaF)+],
119 (38) [(Mes)'], 105 (100) [(C,H,)+], 69 (20) [Gail. Elemental analysis correct.
Received: June 24. 1993 [Z6164IE]
German version: Angeir. Chem. 1993, 105, 1770
Acyclic polysulfanes X-S,-X
form extensive homologous series." -71 Both 'H NMR spectra['] and HPLC
analyses". 3,'I show that n can have values of 35 and above.
Only compounds of up to eleven S atoms have been isolated
in pure form, however,L4l and structure determinations have
only been carried out on sulfanes of up to six S atoms.''.
This is because longer acyclic sulfanes are difficult to isolate
and crystallize, since such compounds are thermally labile
and tend to form oils, honeylike solids, and microcrystalline
powders because of the many possible torsional isomers. We
report here on the first synthesis of dicyanononasulfane
S,(CN),, as well as on its crystal packing and molecular
structure, which shows a chainlike molecule of 13 atoms.
S,(CN), was prepared analogously to the synthesis of the
short-chained members S,(CN), (n = 3-8)[61from S7CI,[71
and Hg(SCN), [Eq. (a)]. Monoclinic crystals are formed,
S,CI,
[l] H. Schmidbaur, H.-E Klein, K Eiglmeier. Angeir. Chem. 1967, 79, 821;
Angebs. Chem. Int. Ed. Engl. 1967, 6. 806.
121 H. Schmidbaur, J. Weidlein, H.-F. Klein, K. Eiglmeier. Chem. Ber. 1968,
101.2268.
[3] H. Schmidbaur. H.-F. Klein. Chem. Ber. 1968, 101. 2278.
[4] B. Neumiiller, F. Gahlmann. Z . Anorg. A&. C h e m 1992. 612, 123.
[5] Crystal data for 1.THF (-70°C): space group Cccu. a=1173.1(2),
b = 2103.1(2). c =1503.6(2) pm. V = 3710(1)x 10bpm3. Z = 4. pcSicd
=
1.300 gcm-', (1)scan, 20 = 4-50', 1037 observed independent reflections
(F,> 3u(F0)),atomic positions of H atoms refined with common temperature factors (H atoms of the disordered THF molecule were not refined),
numerical absorption correction (p = 14.91 cm-'), R = 0.044, R, =
0.042. Siemens R3jP3 four circle diffractometer. Mo,, radiation, graphite
monochromator.
161 Crystal data for 2.THF ( - 80°C): space group R3, u = b = 2255.0(1),
c = 2120.3(2) pm, V = 9337(1) x 10" pm'. 2 = 6, pen,‘,, = 1.436 gem-', u
scan. 20 = 4-120'. 3069 observed independent reflections (F,>3a(Fo)),
1702
'rj VCH Verlugsgesellschaft inbH, 0.69451 Weinhcim. 1993
Unbranched
+ Hg(SCN),
--t
S,(CN),
+ HgC1,
(a)
which melt at 36-38 "C and decompose at 20 "C within 24
hours to form a red polymer, but which can be stored at
- 50 "C without decomposition. The X-ray analysis,['' car[*] Prof. Dr. R. Steudel. DipLChem. K. Bergemann
Institut fur Anorgdnische und Analytische Chemie
der Technischen Universitit
Straae des 17. Juni 135, Sekr. C2. D-10623 Berlin (FRG)
Telefax: Int. code + (30)3142-6519
Dr. J. Buschmann, Prof. Dr. P. Luger
Institut fur Kristallographie der Freien Universitlt
Takustrdne 6. D-14195 Berlin (FRG)
[**I Sulfur Compounds, Part 171. This work was supported by the Deutsche
Forschungsgemeinschaft, the Fonds der Chemischen Industrie. and the
Graduiertenkolleg Freie Universitlt -Technische Universitat. Part 170: [I]
0570-0833/93//212-1702S 10.00+ .2S/0
Angen. Chem.
hi.
Ed. Engl. 1993. 32, No. 12
ried out at - 110 "C showed that the S,(CN), molecule has
C , symmetry. The terminal SCN groups are almost antiparallel to each other (Fig. 1). The S, chain does not have the
ergetically more favorable than a helical conformation. Furthermore, the structure determination of S,(CN), yields for
the first time information about the possible conformation
of polymeric sulfur obtained by extraction from quenching
of sulfur vapor or melts (random coil polymer). This sulfur
is used in large quantities for rubber vulcanization.
Fig. 1. Conformatlon of the S,(CN), molecule (the angle between the lines
through S1 and N1 and through SY and N2 is 170.7"). Nuclear distances [pm]:
Nl-Cl 113(1). Cl-Sl 171.1(8). S 1 4 2 207.8(2), S 2 3 3 204.1(2), S3-S4 206.2(4).
S4-S5 205.7(3). S5-S6 205.5(3), S 6 3 7 205.5(4). S7-SB 204.1(3), S8-SY 207.6(3).
SY-C2 170.6(8). C2-N2 114(1): valence angles [ '7: NI-C1-Sl 177.2(8). C1-Sl-S2
98.8(3). SX-SY-C2 100.1(3).SY-CZ-N2 177.2(7); torsion angles ["I:Nl-Cl-SLS2
- 173(15). Cl-SI-S2-S3 84.3(3). SI-S2-S3-S4 85.7(1). S2-S3-S4-S5 -80.2(1),
S3-S4-S5-S6 - 86.3( 1). S4-S5-S6-S7 87.3(2). S5-S6-S7-S8 94.8(1). S6-S7-SB-S9
-94.2(1). S7-SX-SY-CZ 82.1(3), SB-S9-C2-N2 - 151(13).
Fig. 2. Packing of S,(CN), molecules in the crystal. Open spheres correspond
to the S atoms, solid spheres to the C atoms, and shaded spheres to the N atoms.
expected stretched (helical) conformation, but resembles a
part of the molecular structure of the S,, ring:19"' the signs
of the torsion angles r of the S-S bonds, which would all be
the same for a helix, are + + - - +
- + (S,,:
+ + - - + + - -. . .). The values of the torsion angles /rI
are in the usual region of 80-95". The S, unit has approximate C, symmetry; the S-S-S valence angles lie between
104.3(1 ) and 106.8(1)". The S-S internuclear distances vary
between 204.1 and 207.8 pm (average value 205.8 pm; average value for s,, 205.2 prnrgbJ).Noticeable is that the "terminal" S-S bonds are the longest (207.7 pm) and the two
neighboring ones are the shortest (204.1 pm). Similar observations were made for S,(CN),, and the resonance structures shown in Scheme 1 were proposed."']
+
.. .. ..
-SS-S-CZN:
.. .. ..
@
.. 0
:S-CSN:
ts -S=S
Scheme 1
The low melting point T , = 310f 1 K of S,(CN), shows
on the one hand that the intermolecular interactions can
only be weak, but on the other hand that the melting entropy
AS,,, must be exceptionally large since T,,,= AH,,,/AS,,,
(AH,,, = melting enthalpy). The large entropy increase can
be explained by the torsional isomerism of the S-S bonds,
because each 7 value can be about + 90" or -90" and thus
for eight S-S bonds 2' = 256 conformational isomers of
similar energy (including enantiomers) exist." The rotational barrier" for cumulative S-S bonds is only approximately 24 kJmol-', so that a mixture of conformers can
occur on melting.
The shortest contact distances in S,(CN), (S . . .N: 307,
C . . . N: 3 18 pm) correspond roughly to van der Waals distances, yet all the SCN groups in the crystal arrange themselves parallel or antiparallel to the b axis of the monoclinic
unit cell, which points to weak dipole-dipole interactions
(Fig. 2). Since the CN groups are neither bulky nor particularly electronegative, the structure of S,(CN), can serve as
model for the structure of other acyclic polysulfanes with
small substituents, for example H,S,, S,CI, or (CH,),S,, for
which a compact structure in the solid state is possibly enAngwt Chern. Int. Ed. Engl. 1993. 32, No. ( 2
6
Experimental Procedure
Freshly prepared S,CI, 171(1.25 mmol) was dissolved in 20 mL anhydrous CS,,
cooled to - l O T , and Hg(SCN), (1.56 mmol) was added with stirring. After
2 h the solvent was decanted from the HgCl,/Hg(SCN), mixture. cooled to
50 "C (1 2 h), decanted again, and warmed to 20 "C. n-Hexane was added until
the mixture became cloudy. On cooling to -50°C pure S,(CN), crystallizes
Correct C, N, S analyses; I3CNMR (67.69 MHz, CDCI,. 25°C):
(yield 21 YO).
6 = 109.9; FT Raman: V [cm-'1 = 2153/2145 (C-N), 666 (C-S), 483/466/454/
438/427/402 (S-S and &).
~
Received: 2 July, 1993 [Z6186IE]
German version: Angew. Chem. 1993, 105, 1781
[I] Review: R. Steudel, M. Kustos in Encyclopedia Uj'Inorgank Chemistry.
Vol. 7 (Ed. R. B. King), Wiley, Sussex, in press.
[2] J. Hahn, Z. Nurnrforsch. B 1985, 40, 263.
[3] N. Etzenbach, J. Hahn, F. Rabet, Bruker Reporf 1990. 44.
[4] H. Schmidt, R. Steudel, 2. Nuiurforsch. 5 1990, 45, 557; H. Schmidt,
Dissertation, Technische Universitat Berlin, 1992.
151 M. Kustos, J. Pickardt, J. Albertsen, R. Steudel, Z. Naturforsch. B 1993,
48. 928.
[6] H. Lecher, A. Goebel, Ber. Dtsch. Chem. Ges. 1922. 55, 1481, 1483: F.
Feher, H. Weber, Chem. Ber. 1958.91.642 [Thecompounds S,(CN), with
n = 5,7,8 described in this work were obtained as oils which still contained
3-7% HgCI,].
[7] R. Steudel. R. S t r a w , D. Jensen. CAem. Z f g . 1985, 109, 349.
[8] Crystal data for S,(CN), (crystallized from CS,/n-hexane): M , =
340.6gmol". monoclinic, space group P2,, u = 835.9(3), h = 590.6(1),
c = 1222.0(4)pm, /3 = 102.30(1/", V = 589.43 x lo6 pm3. Z = 2. p,,,, =
1.919gcm-', p(Mo,,) =15.74cm-'. Data collection at -110°C on a
Siemens four-circle diffractometer (Mo,, radiation. 2. = 71.069 pm) with
open 1 1 0 " - ~circle and a cold gas stream for temperature adjustment.
Crystal dimension: 0.3 x 0.14 x 0.1 1 mm. 1565 independent reflections
with I > 3a(I), 4' < 28 < 58". 117 parameters refined, R = 0.037. Further
details of the crystal structure investigation may he obtained from the
Fachinformationszentrum Karlsruhe, Gesellschaft fur wissenschaftlichtechnische Information mhH, D-76344 Eggenstein-Leopoldshafen(FRG)
on quoting the depository number CSD-57493, the names of the authors,
and the journal citation.
[Y] a) A. Kutoglu, E. Hellner, Angew. Chem. 1966, 78, 1021; Angew. Chem.
I n f . Ed. Engl. 1966.5.965; b) J. Steidel, R. Steudel, A. Kutoglu, Z . Anorg.
A&. Chem. 1981, 476, 171.
1101 R. Steudel, K. Bergemann, M. Kustos, 2. Anorg. A&. Chrm., in press.
[l I] In reality the number of conformers is slightly smaller, since certain torsion
angle combinations would lead to a too close approach of nonbonded
atoms.
[12] R. Steudel. Z . Naturforsch. B 1983, 38. 543, and references therein.
VCH Vrrliigsgesellsrl~uftmbH. 0-69451 Wrinheim, 1993
0.570-0833/93/I212-1703$1U.U0+ . 3 I U
1703
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