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Novel BN Ligand with Six Competing Electrons around the Transition Metal Coordination Center.

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other layer sequences is to be expected. By analogy to the
nomenclature of polytypes, the following symbols have
been selected for dodecasil polytypes:
Layer sequence
Lattice constants [A]
the sandwich complex 3, identified as isomerically pure
on the basis of the MS[2b1and NMR
the two ligands 1 are held together by two central n-bonded nickel
As shown by the X-ray structure
of 3 [NiNidistance 264.3(1) pm] the two ligands 1 are q3/q4-fixed to
the Ni2 dumbbell in a syn-arrangement to each other. The
C3 atoms of 1 each form a 2e/3c bond with both Ni atoms
in 3. The sequence of the ring atoms-reading clockwiseis different in each ligand 1.
Of these, we have obtained dodecasil-1H as single crystals. Clathrasils appear to be suitable as thermally stable,
water- and acid-proof storage materials for radioactive noble gases produced in the generation of nuclear energy.
[I] H. Gies, F. Liebau, Acta Crystallogr. A 37 (1981) S 187.
(21 M. von Stackelberg, H. R. Miiller, Z. Elektrochem. 58 (1954) 25.
[3] A group from Mobil Oil has succeeded independently in synthesizing a
phase of this type, and using X-ray powder data established the structural
analogy to clathrate hydrates of type 11: F. G. Dwyer, E. E. Jenkins, USPat. 4287 166 (1981); J. L. Schlenker, F. G. Dwyer, E. E. Jenkins, W. J.
Rohrbaugh, G. T. Kokotailo, W. M. Meier, Acta Crystallogr. A 37 (1981)
[4] The proposed term "dodecasil-3C" comprises the name of the host lattice
(dodecahedron) and the name of the lattice forming compound (silica),
the number of layers in the unit cell (3). and the crystal system of the
ideal framework (cubic).
[5] R.-D. Penzhorn, P. Schuster, DBP 2948515 (1981).
Novel BN Ligand with Six Competing Electrons
around the Transition Metal Coordination Center**
By Roland Koster* and Giinter Seidel
Hexaalkyl-A'- 1,2,5-azasilaboroIine~~~~~
coordinate as 4nligands to transition metals['"]. We have now synthesized in
an analogous way[Ib1the 3-vinyl-derivative 1 in order to investigate the complexation of the n bonds of the triene
which it contains.
Reaction of 1 (6('' B) = 46)[*"]and nonacarbonyldiiron at
160 " C leads via cleavage of C O to formation of the mononuclear complexes 2a (yellow, 6( "B) = 50.3[2"1) and 2b
(orange color, 6("B)= 18.2['"]) in 65% overall yield in the
stable molar ratio 4 : 1. Composition and structure of these
q4-isomers are confirmed mass spectrometrically[2"1and by
'H-NMR["] as well as "C-NMR spectroscopy['"]. 2a and
2b can be separated from each other chromatographically
Reaction of ttt- 1,5,9-cyclododecatrienenickeland 1 at
ca. 80 C affords the diamagnetic, red-black dinuclear
sandwich complex 3 [m.p. 134--136°C (dec.); mass spectrum[2hl:m/z 558 (Ni2)], which is air-stable for a short time
at room temperature. The "B-NMR signal of 3
[6('' B) = 26.4''"]] and the large shifts A6( 'H) and A6( ''C) of
the two P-methylallyl groups of 3 compared to 1 clearly demonstrate that 3 contains two q6-coordinated ligands. In
[*] Prof. Dr. R. Koster, G. Seidel
Max-Planck-lnstitut fur Kohlenforschung
Kaiser-Wilhelm-Platz I, D-4330 Miilheim an der Ruhr (Germany)
[**I Boron Compounds, Part S - P a r t 52: [la].
Received: September 23, 1981 (Z 31 IE]
German version: Angew. Chem. 94 (1982) 214
Angew. Chem. Int. Ed. Engl. 21 (1982) No. 3
/ \
Apart from the transition metal n complexes with isolated bis(n-allyl)-str~ctures[~~
only a few compounds with
linear141or c r ~ s s e d conjugated
q6-C6 ligands are known.
The bonding situation in 3 resembles that in bis(pentadienyl)dini~kel'~"~
with a cumulated electron system.
The competition of the n electrons of hetero- and homo1,3,5-hexatrienes during complexation with transition metals-derivable from the structures of 2a, 2b, and 3-opens up, inter alia, new prospects for catalysis and its control.
2a and 2b: A suspension of Fe2(CO), (2.07 g, 5.69
mmol) and 1 (2.89 g, 13 mmol) in mesitylene (10 mL) is
heated under reflux (ca. 160°C) for 3 h. 484 mL (21.6
mmol) of C O are liberated with concomitant formation of
an Fe-mirror. After filtration (small amount of Fe) the solution is evaporated to dryness at 5 3 0 ° C (bath)/lO-' torr
and the residue sublimed at 5 6 0 ° C / 1 0 - 3 torr: 2.6 g (63%)
of an orange-red, wax-like mixture (HPLC[2d1)of 78% 2a
and 22% 2b, respectively.
3: The dark-red suspension of ttt- I ,5,9-cyclododecatrienenickel (1.7 g, 7.7 mmol) and 1 (5.6 g, 25 mmol) is
heated for 4 h at ca. 80°C. After evaporation of the darkbrown suspension to dryness at 5 6 0 ° C (bath)/10-3 torr
the residue is crystallized from ca. 30 mL of pentane at
-78°C: 1.6 g (75%) of 3, m.p. 134--135°C (dec.).
Received: October 19, 1981 [Z 33 IE]
German version: Angew. Chem. 94 (1982) 225
[I] a) R. Koster, G. Seidel, S. Amirkhalili, R. Boese, G. Schmid, Chem. Ber.
115 (1982) 738; b) R. Koster, G. Seide1,Angew. Chem. 93 (1981) 1009; Angew. Chem. Int. Ed. Engl. 20 (1981) 972.
[21 Measurement a) R. Mynott: b) D. Henneberg, W. Joppek; c) R. Benn, A.
Rufinska, G. Schroth; d) G. Schomburg, A. Deege: e) C. Kriiger, A.
Chiang, Miilheim an der Ruhr.
[31 P. W. Jolly, G. Wilke: The Organic Chemistry of Nickel,Academic Press,
New York 1974, Vol. 1, p. 336ff.
0 Verlag Chemie GmbH, 6940 Weinheim, 1982
0570-0833/82/0303-0207 $ 02.50/0
[41 a) D. J. Brauer, C. Kriiger, J . Organomet. Chem. 122 (1976) 265; b) H.
Lehmkuhl, R. Paul, R. Mynott, Liebigs Ann. Chem. 1981, 1139.
[S] a) W. Keim, Angew. Chem. 80 (1968) 968; Angew. Chem. Int. Ed. Engl. 7
(1968) 879; b) R. Rienacker, H. Yoshiura, ibid. 81 (1969) 708 and 8 (1969)
677; C. Kruger, ibid. 81 (1969) 708 and 8 (1969) 678.
From the 6( I9F) values it is clear that different sets of CF3
groups are present in 2a, 2b, and 5 [-65.1, -65.6 (2a);
-67.5, -68.0 (2b); -68.7, -69.4 (5)J since the first step
of a ligand permutation process is slow on the time scale of
the NMR experiment[-’”].The 6(’H) values for 3 and 4 are
10.8 and 4.00, respectively (,JPH = 15.1 Hz).
A Stable Tetraalkoxy(hydroxy)phosphorane and
Phosphorane Oxide Anion by Hydrolysis of
Tetraalkoxy(ha1ogen)phosphoranes” *
Received: May I I , 1981,
in revised form: January 22, 1982 [Z 34 IE]
German version: Angew. Chem. 94 (1982) 212
By Gerd- Volker Roschenthaler* and Werner Storzer
Tetraalkoxy(hydroxy)phosphoranes were postulated as
intermediates in the hydrolysis of alkyl(ary1)phosphates
some time ago[’], but until now could only be synthesized
in a few cases by oxidation of the corresponding hydrogen
phosphoraned*]. Hydrolysis of the halospirophosphoranes
2a and 2b, obtainable by treating the trihalophosphor a n e ~ [ ~l”a’ and l b with dilithium perfluoropinacolate in
neutral or alkaline aqueous ether solution, led to the hydroxyphosphorane 3 (m. p. = 72 “C, 78% yield) and potassium phosphorane oxide 5 (m. p. = 118 “C, 100% yield), respectively, without cleavage of the P-0
ring bonds to
form a P=O bond. A tautomeric monocyclic form[21of 3 is
not observed. The methoxy derivative 4 (m. p. = 68 “C, 92%
yield) is obtained in the same way using methanol.
R = H
Scheme I . @ I : I ; - 196 to + 160°C (10 h) and + 2 0 ” C (24 h), respectively,
petroleum ether extraction, Et:O, sublimation: 2a (62%, m. p . = 6 2 ” C ) and 2b
(43%, m.p.= 82”C), respectively. @ I mL of water or methanol is added to a
stirred solution of 0.003 mol 2a or 2b in 20 mL of E b O ; after 30 min the organic phase is separated off and the aqueous phase extracted three times
with ether. The mixture was then dried over Na2S04, concentrated and the
product recrystallized from Et,O. 01.0 g of KOH in 5 mL of water is added
to a stirred solution of 0.01 mol 2a o r 2b in 30 mL of EtrO; after 1 h the mixture is extracted three times with 20 mL of ether, dried over N a r S 0 4 and the
solvent removed; yield 7.5 g 5.
The ring-forming OC(CF,),C(CF,),O-substituents (electron withdrawing properties and spacial requirements of
the CF3 groups) produce the remarkable stability of 3, 4,
and 5. Hence, 3 can be sublimed out of concentrated sulfuric acid. The pK, value was determined as 2.Or4I.
The composition and constitution of all the novel compounds have been confirmed by elemental analysis, 70 eV
mass spectra (apart from 5 ) , as well as by NMR spectra[’].
The highest mass ions are M + - F for 2,3, and 4, and the
most frequent fragment is CF: for 2 and 3, and M + -CF3
for 4. The 6(3’P) values are typical of phosphoranes
[-12.4(2a), -37.9(2b), -34.5(3), -34.5(4), -37.9(5)].
[*] Prof. Dr. G.-V. Roschenthaler
Fachbereich 3 der Universitat
Bibliothekstrasse, D-2800 Bremen 33 (Germany)
Dr. W. Storzer
Lehrstuhl B fur Anorganische Chemie der Technischen Universitat
Pockelstrasse 4, D-3300 Braunschweig (Germany)
[**I This work was supported by the Deutsche Forschungsgemeinschaft
0 Verlag Chemie GmbH. 6940 Weinheim. 1982
[I] F. H. Westheimer, Acc. Chem. Res. I (1968) 70.
[2] A. Munoz, B. Garrigues, M. Koenig, Tetrahedfon 36 (1980) 2467.
131 a) G:V. Roschenthaler, K. Sauerbrey, J. A. Gibson, R. Schmutzler, Z.
Allg. Anorg. Chem. 450 (1979) 79; b) G.-V. Roschenthaler, K. Sauerbrey,
R. Schmutzler, Z. Noturforsch. 8 3 4 (1979) 107.
14) Cf. I. Granoth, J. C. Martin, J. Am. Chem. SOC.101 (1979) 4618.
IS] Saturated solutions in C D S N : TMS. CCI,F internal ( ‘ H , ‘“F), 85%
H,PO,external standard (“P).
Vehicle Mechanism, A New Model for the
Interpretation of the Conductivity of Fast Proton
By Klaus-Dieter Kreuer, Albrecht Rabenau*, and
Werner Weppner
The conduction of protons in solids is generally explained, as in the case of liquid electrolytes, in terms of the
Grotthuss Mechanism[’]: The protons move in an infinite
network of hydrogen bonds. The process consists of two
steps, the translation of a proton from an oxonium ion[*]to
a water molecule by tunneling in a hydrogen bond and
subsequent reorientation (rotation) of the water molecule
thus formed in order to be able to take u p the next proton
(Fig. I , top).
Our investigations lead to strong arguments in favor of
another process, which we call the Vehicle Mechanism.
According to this model the proton does not migrate as
H + but as OH :, N H :, etc.. bonded to a “vehicle” such as
HzO, NH3, etc. The “unladen” vehicles move in the opposite direction (Fig. 1, bottom). The vehicle shows a diffusion coefficient corresponding to the proton conduction
and behaves like a Bronsted base (proton acceptor) towards its crystallographic environment.
Fig. I . Model of proton conduction. Top: Grotthuss Mechanism; the protons
are passed along the hydrogen bonds. Bottom: Vehicle Mechanism: the
movement takes place with the aid of a moving “vehicle”, e . g . . H 2 0 or NH,
as complex ion ( H , O + or NH:).
The Nernst-Einstein relation between the diffusion
(translation) of the vehicle and the conductivity of protons
is fulfilled, but no correlation between the rotation of the
vehicle and the conductivity has been found (Table 1).
The Vehicle Mechanism makes the extremely large temperature factors which have been observed in X-ray and
neutron diffraction studies understandable“”] and is consistent with the observation that practically all good proton
[*] Prof. Dr. A. Rabenau, K. D. Kreuer, Dr. W. Weppner
Max-Planck-lnstitut fur Festkorperforschung
Heisenbergstr. I , D-7000 Stuttgart 80 (Germany)
Angew. Chem. Int. Ed. Engl. 21 (1982) No. 3
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electrons, metali, coordination, around, competing, transitional, novem, six, center, ligand
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