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Diazaboracyclopropane.

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The molecular structure of the osmium complex 3c was
determined by X-ray structural analysis (Fig. l)I6l, The
S:" unit is linked via S l , S4, and S7 to Os, which attains
the preferred octahedral coordination for oxidation state
2. As far as the structural data are concerned, special attention is drawn to the different 0 s - S and S-S bond
lengths. Compared to 0s-S1 and Os-S7, the significantly
shorter Os-S4 distance indicates that in addition to the donor bond from S4 to the 0 s atom an acceptor bond may be
present, i.e., not only A but also the resonance structure B
must be considered in a description of the bonding in 3b,
c. The unique role of S4 in the OsS, bicyclic system can
also be seen in the larger 0s-P1 bond (trans to S4) and in
the elongation of the S3-S4 and S4-S5 bonds.
+
A
B
To the best of our knowledge, 3b, c are the first metal
complexes in which an MS, unit is present and an S:' ion
is coordinated as a tridentate ligand. Recently, monocyclic
MS, ring systems with n = 6[7a1and n = 9[7b1have been prepared with M = C u or Au and their structures characterized. It seems interesting that the bicyclic OsS, moiety has
the same "paddle-wheel"-like exo/endo-conformation as
the Si' ion in S8(AsF6),[*].
by qouting the depository number CSD 50982, the names of the authors
and the journal citation.
[7] a) A. Muller, U. Schimanski, Inory. Chim. Acra 77 (1983) L187; b) G .
Marbach, J. Strahle, Angew. Chem. Y6 (1984) 229; Angew. Chem. Int. Ed.
Engl. 23 (1984) 246; A. Muller, M. Komer, H. Bogge, E. Krickemeyer, K.
Schmitz, Inorg. Chim. Acta 85 (1984) L39.
[8] C. G. Davies, R. J. Gillespie, J. J. Park, J. Passmore, Inorg. Chem. I0
(1971) 2781.
Diazaboracyclopropane**
By Uwe KlingebieP
Strained b o r o n - p h o s p h o r ~ s ~ 'and
-~~ boron-carb~n[~-~I
three-membered ring systems have been synthesized in the
last ten years by several groups. Among the thoroughly
studied boron-nitrogen heterocycles~7~x11,
no strained BN2ring compound was previously known.
Like d i h a l ~ s i l a n e s ~ dihaloboranes''.
~~~',
''I react with lithiated hydrazines to afford, preferentially, six-membered
rings. The synthesis of an SiN2 three-membered ring using
the bulky di-tert-butyldifluorosilane was recently reported.
Preparation of a BN2 three-membered ring should also be
favored by the presence of sterically demanding substituents on the nitrogen and boron atoms.
As expected, reaction of the doubly lithiated N,N'bis(tert-butyldimethylsi1yl)hydrazine 1 with difluorobis(trimethylsily1)aminoborane 2 leads to the diazaboracyclopropane 1,2-bis(tert-butyldimethylsilyl)-3-[bis(trimethylsilyl)amino]diazaboriridine) 3.
fBuMe,Si,
SiMe,tBu
L i'
Received: June 22, 1984 [Z 894 IE]
German version: Angew. Chem. 96 (1984) 813
Angew. Chem. I n [ . Ed. Engl. 23 (1984) No. I #
F,R-N(
SiMe,
Li
1
-'
L'F
2
CAS Registry numbers:
Ib, 78789-89-6; Ic, 84108-58-7; 2b, 92346-64-0; ZC, 92346-65-1; 3b, 9234666-2; 3c, 92346-67-3
[l] a) M = F e : H. H. Karsch, H.-F. Klein, H. Schmidbaur, Angew. Chem. 87
(1975) 630; Angew. Chem. In[. Ed. Engl. 14 (1975) 637; J. W. Rathke, E.
L. Muetterties, J. Am. Chem. Sor. 97 (1975) 3272; b) M = Ru: H. Werner,
R. Werner, J. Organornet. Chem. 209 (1981) C60; c) M = O s : H. Werner,
J. Gotzig, Organometallics 3 (1983) 547.
[2] H. H. Karsch, H.-F. Klein, H. Schmidbaur, Chem. Ber. 110 (1977) 2200;
H. H. Karsch, ibid. 110 (1977) 2213, 2699; 111 (1978) 1650.
[3] a) Y. Wakatsuki, H. Yamazaki, J. Organornet. Chem. 64 (1974) 393; b)
Ch. Burschka, K. Leonhard, H. Werner, Z. Anorg. Allg. Chem. 464 (1980)
30.
141 a) Experimental procedure: A solution of lb ( l c ) (0.34 mmol) in 5 mL
benzene is treated with Sn (87 mg, 0.34 mmol) and stirred for 1 h. The solution becomes warm and a dark oily precipitate is formed. After decanting off the solution, the precipitate is washed with hexane (3 x 5 mL),
dried, dissolved in 2 mL CHzC12, and chromatographed o n silica gel (Ru)
or AI2O3 (Woelm, activity 111) ( 0 s ) . Addition of hexane to the concentrated solution (ca. 2 mL) gives a dark brown crystalline solid which is repeatedly washed with hexane and dried in vacuo. Yield 64% Zb (67%,
Zc); m.p.=93"C, dec. (147"C, dec.). After dissolving 2b, c in acetone and
covering with hexane, orange-red crystals are formed; m.p.= 137"C, dec.
(3b) (161 "C, dec., (3c)).-b) The sulfur content is particularly different for
2b, c and 3b, c. 2b: calc. 36.96, found 37.01; Zc: calc. 31.50, found 31.62;
3b: calc. 40.53, found 40.32; 3c: calc. 34.91, found 34.82%.
(51 a) 'H-NMR (60 MHz, 2S°C, CH2Cl2,int. TMS). 2b, 3b: 6(P'Me3)= 1.74
(d, J(PH)=8.5 Hz), 6(P2,'Me3)= 1.39 (vt, N=7.5 Hz); Zc, 3c:
6(P'Me3)=1.89(d,J(PH)=8.5 Hz),A(P2.'Me3)= 1.50(vt, N = 8 . 1 Hz).-b)
"P-NMR (90 MHz, 2 5 T , CDCI,, ext. 85% H3P04). Zb, 3b:
6(P')= -5.99, 6(P2.')= -9.05, J(P'P'.')=32.8
Hz; 2c, 3 ~ :6(P')=
- 50.86, 6(P2.') = - 52.86, J(P'P2') =22.8 Hz.
[6] Monoclinic, space group P2,/n, Z = 4 , a=938.4(3), b = 1487.3(4),
c = 1562.3(5) pm, 8=98.81(2)"; V=2154.6x lo6 pm'. MoKa (L=71.073
pm); 4O< 28<50" (Nicolet P3); 3376 independent reflections with
Fg,>3u(Fo);R,,,=0.0416, R,,,,,,=0.0333. Further details of the crystal
structure determination can be obtained from the Fachinformationszentrum Energie Physik Mathematik, D-75 14 Eggenstein-Leopoldshafen
SiMe,
+
N-N(
lBuMe,Si\
N,-y'
SiMe,tBu
R
Me&
/
N
\
SiMeB
3
The structure of the BN2 ring system was elucidated by
C H elemental analysis and by cryoscopic determination of
the molecular mass in cyclohexane (M,=432); the presence of a dimer, i.e. a B2N4ring system[''], can therefore be
excluded also in solution. Since it has not yet proved possible to isolate single crystals suitable for an X-ray structure investigation, the configuration assigned to this threemembered ring is corroborated by NMR data. The "BNMR shift (6=27.2) occurs in the region associated with
sp2-hybridized boron. The nitrogen is-in part, certainly
because of the bonded silyl groups-sp2-hybridized; the
I4N-NMR shift is observed at 6 = -329 (rel. CH3N0,).
The sharp 'H- and "C-NMR signals indicate the presence
of equivalent substituents in the ring plane. The Z9Si-NMR
signals occur in the region expected.
Hence, the NMR data for this silyl- and silylamine-substituted three-membered ring differ also from those of the
recently synthesized BN2 ring which bears isopropyl
groups at the nitrogen.
[*I Prof. Dr. U. Klingebiel
(**I
Institut fur Anorganische Chemie der Universitat
Tammannstrasse 4, D-3400 Gottingen (FRG)
This work was supported by the Fonds der Chemischen Industrie.
0 Verlag Chemie GmbH. 0-6940 Weinheim. 1984
0570-0833/84//#10-#R15 $ 02.50/0
815
Procedure
A solution of 1 (0.05 mol) in 200 mL n-hexane is cooled to -30°C and to
this is added aver 4 h, with constant stirring, a solution of 2 (0.05 mol) in 150
mL n-hexane. After being warmed up to room temperature, precipitated LiF
is centrifuged off. The solvent is removed using an oil pump and 3, which
precipitates out even at this stage, is purified by dissolution in a little n-hexane at room temperature and precipitation at -3OOC. Yield: 10.5 g (85%);
Fp=69"C; MS (70 ev): m/z 429 (15) M a (with theoretical B-isotope abundance), 414 (5) ( M " -CHI), 372 (100) ( M e -C4HY); ' H - N M R (CH2C12,TMS
int.): 6=0.10 (SiMe2), 0.26 (SiMe,), 0.97 (CMe,); "B-NMR (CH2C12/C6D6,
BF3.0Eti ext.): 6=27.2; "C-NMR (CH2CI2/C6D6,TMS int.): 6 = -3.34
(SiMe2), 3.24 (SiMe,), 19.72 (SiCMe,), 27.26 [SiC(CH,),]; I4N-NMR (CDC13,
CH,NO2 ext.): &= -329; 29Si-NMR (CH2Cl2/C6D6, TMS int.): 6=7.25
(SiMe2CMe3), 12.88 (SiMe,).
Received: June 26, 1984;
supplemented: July 24, 1984 [Z 901 IE]
German version: Angew. Chem. 96 (1984) 807
CAS Registry numbers:
I , 92396-56-0; 2, 2251-46-9; 3, 92365-99-6
[ I ) M. Baudler, A. Marx, J. Hahn, Z . Nutwforsch. 8 3 3 (1978) 355.
[21 M. Baudler, A. Marx, Z . Anorg. Allg. Chem. 474 (1981) 18.
[3] M. Feher, R. Frohlich, K . F. Tebbe, Z . Anorg. Allg. Chem. 474 (1981)
31.
[4] H. Klusik, A. Berndt, Angew. Chem. 95 (1983) 895; Angew. Chem. Int.
Ed. Engl. 22 (1983) 877.
[S] C. Habben, A. Meller, Chem. Ber. 1/7(1984) 2531.
161 C. Pues, A. Berndt, Angew. Chem. 96 (1984) 306; Angew. Chem. In/. Ed.
Engl. 23 (1 984) 3 13.
[7] B. Maouche, J. Gayoso, In?, J . Quantum Chem. 1983, 891.
IS] J. Haiduc: The Chemistry oflnorgnnie Ring Systems, Wiley-Interscience,
London 1970.
[9] J. Hluchy, U. Klingebiel, Angew. Chem. 94 (1982) 292; Angew. Chem.
Int. Ed. Engl. 21 (1982) 301; Angew. Chem. Suppl. 1982, 750.
[lo] K. Barlos, H. Noth, Z . Na/urfbrsch. 835 (1980) 407, 125; H. Noth, W.
Winterstein, Chem. Ber. I l l (1978) 2469.
[ I l l F. Dirschl, H. Noth, W. Wagner, J . Chem. Soc. Chem. Commun., in
press.
With X = CN, on a preparative scale, this reaction yields
salts of the dicyanophosphide ion['], which has previously
been obtained by reduction of P(CN),[''. Lithium triphenylstannide, alkali-metal alkyl- and a r y l p h o s p h i d e ~ ~as
~],
well as alkali-metal phosphites, phosphonites, and phosphinites react a n a l o g ~ u s l y ' ~ ~ .
Moreover, in certain favorable cases P4 may be degraded without disproportionation [eq. (2)]. Here, the base
Xo effects breakdown of P4 into two P,-halves. Their 10valence electron system (which in contrast to N2 cannot
sufficiently n-stabilize) is Supplemented in this way with
four electrons by addition of two X" ligands.
+ 2xe
1/2P,
-
Pzx:Q
(2)
With NaX = sodium diethyl- and sodium diphenylphosphinite, both reactions were verified. Decisive is the molar
ratio of P4 to X": If the molar ratio is 1 : 4 in tetrahydrofuran, the salt 1 forms momentarily and completely at room
temperature [eq. (3) ( 2 ) , X = PR,O]. Excess base remains
unreacted. Reduction of the amount of base to a level such
that two phosphinite ligands are no longer available per P2
moiety leads to disproportionation of a fraction of the
phosphorus into 2a and Na3P7 [(eq. (4)p(1), X = P R 2 0 ,
n = 7/31. At the molar ratio 1 :2.4, only disproportionation
occurs. Addition of still less base gives [e.g., according to
eq. ( 5 ) r (I), n = 81 as reduction products higher sodium
polyphosphides which finally precipitate.
P,
+
4 NaOPK,
-
R
I
O= -P-P2 Nti,
0-
P4-Degradation with and without
Disproportionation""
P4
+ 3 OH' + H 2 0
3 H,PO,O
+ PH3
G. Burget
Institut fur Anorganische Chemie der Universitat
Meiserstrasse I , D-8000 Munchen 2 (FRG)
Prof. Dr. H. G. von Schnering, Dr. D. Weber
Max-Planck-lnstitut fur Festkorperforschung
Heisenbergstrasse I, D-7000 Stuttgart 80 (FRG)
[**I This work was supported by the Deutsche Forschungsgemeinschaft and
by the Fonds der Chemischen Industrie.
816
0 Verlag Chemie CmbH, 0-6940 Weinheim, 1984
(3)
P-
O=P-P-P=O
I
5 P4 + 1 2 MOPRz-
6 PA
b
+ 2 M,P,
(4)
1 :2.4
and thereby formally disproportionates into the P4-fragments 3 P@and P3", which are however strongly modified
by taking u p OH" and He,respectively. Instead of using
the hydroxide ion, we have now studied P4-degradation
with soft anionic bases X" and obtained products in which
the P,-fragments are more easily recognized. The 4-valence
electron particle PQ is stabilized by addition of the two ligands X" to give the anion PX," with an octet configuration at P, and the charge on P3' is shared with a larger or
smaller number of phosphorus atoms to form a polyphosphide [eq. (I)].
[*I Prof. Dr. A. Schmidpeter, DipLChem.
I
=O
R
I
P P-0
[2
1 :4
By Alfred Schmidpeter*, Giinther Burget,
Hans Georg von Schnering, and Dieter Weber
White phosphorus is degraded nucleophilically by aqueous solutions of alkali metal hydroxides, e.g. according to
the following equation
x f'
1
x= =A
9 P, + 8 MOPK,
-
2
4 2
MZP16
(5)
1 :0.9
a, M = Na; b, M = Li; R = Et, Ph
l a and 2a differ markedly in their hydrolytic sensitivity:
whereas l a is decomposed instantaneously by water, 2a
remains stable for several days.
In contrast to sodium phosphinites, lithium phosphinites
react, even when present in a large excess, only in the molar ratio 1 :2.4 according to eq. (4) with disproportionation
to afford 2b and Li,P,. The latter compound (just as
Na3P7) can be identified by comparison of the 31P-NMR
spectra with those of authentic materia113b*51.
If the molar
ratio P4 :base is reduced to 1 :0.9, in addition to 2b an insoluble polyphosphide is formed; its composition, based
on the stoichiometry of eq. (5), is Li2P1613c1.
Upon use of
V57V-0833/84/1V10-0816 $ 02.5V/V
Angew. Chem. I n t . Ed. Engl. 23 (1984) No. 10
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