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Ethoxydiethylaminocarbenepentacarbonyl-chromium(0).

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The product (2)is also a stable, colorless liquid (b.p. 158 "C]
749 torr); m.wt.: calc. 244.47, found 243, in benzene. IHN M R : singlet at 8 = --0.15 ppm (TMS as external standard);
IgF-NMR: singlet at 8 = -77.4ppm (CFC13 as external
standard).
RSOT
(3)
Received: February 6 , 1970
[Z 166 IE]
German version: Angew. Chem. 82, 322 (1970)
Priv.-Doz. Dr. E. Lindner and Dr. G. Vitzthum
Institut fur Anorganische Chemie der Universitiit
Erlangen-Numberg
852 Erlangen, Fahrstrasse 17 (Germany)
E. Lindrier and i:P. Loreriz, unpublished.
E . Lindner. G. Vifzthum. D . Larwner. and I . - P . Lore//-.
Angew. Chem. 82, 133 (1970); Angew. Chem. internat. Edit. 9,
160 (1970).
[3] E. Lincher and C. V i f z f h u r n , 2. anorg. allg. Chem.. in
press.
[4] E. Lindrter and G. Vifzfhttm, Chem. Ber. 102, 4053, 4062
(1 969).
Tris(N-trimethylsilylimido)sulfur and
Bis(N-trimethylsi1ylimido)sulfur Difluoride
Mass spectrum (relative intensities): molecular ion
SF2[NSi(CH3)& (8), Si(CH3); (loo), SFzNzSiz(CH3);
(72), SNZSi(CH3); (28), SiCH; (25), SN; (14), SN+ (14),
SFNSi(CH3); (7.9, N S F Z [ N S ~ ( C H ~ )(3),
~ ] - SFzNSi(CH3);
~
(3), SF[NSi(CH&I; (2), SFzNZSiz(CH3); (2).
IR (cm-1): 580 w, 620 s , 638 s, 700 w, 710 w, 735 w, 760 w,
787 w, 840 w, 889 w, 1258 s, 1302 s, 1430 vs, 2200 s , 3000 vs.
Raman (cm-1): 182, 195, 255, 338, 350, 582, 595, 620, 640,
698, 765, 790, 888, 1265, 1307, 1416, 1425.
Procedure :
NSF3 (30 g, 0.29 mole) is added dropwise to a stirred solution
of LiN[Si(CH3)3]2 (110 g, 0.66 mole) in light petroleum (b.p.
(150ml) at 0°C over a period of 1 h. After
40-60'C)
removal of solvent under reduced pressure, the products are
fractionated in a high vacuum; yield of ( I ) about l o g , of
( 2 ) , 15 g.
Received: February 16. 1970
[Z 167 IE]
German version: Angew. Chem. 82, 324 (1970)
. ..
~
-
[*I
Prof. Dr. 0. Glemser and Dipl.-Chem. J . Wegener
Anorganisch-Chemisches Institut d e r Universitgt
34 Gottingen, Hospitalstrasse 8-9 (Germany)
[ I ] Cf. R. Appel and B. Ross, Chem. Ber. 102, 1020 (1969);
Angew. Chem. 80, 561 (1968); Angew. Chem. internat. Edit.
7, 546 (1968).
By Osknr Gleinser and Jocrcliiiri Wegener[*]
We have now succeeded in synthesizing, for the first time, a
derivative of the hitherto unknown sulfur triimide, namely
tris(N-trimethylsilylimido)sulfur ( I ) , by reaction of sulfur
nitride trifluoride with lithium bis(trimethylsily1)amide in
light petroleum at O°C; the reaction also affords bis(N-trimethylsilylimido)sulfur difluoride (2). ( 1 ) is the only compound to have been discovered so far that contains 3-coordinate sulfur in the oxidation state + 6 and yet does not
polymerize "1.
Ethoxydiethylaminocarbenepentacarbonylchromium(0)
By Ernsf 0.Fisclter and Hans 1. KollmeierI+l
Alkyl- and aryllithium compounds react with transition
metal carbonyls t o give lithium acylcarbonylmetalates, which
can be converted into alkoxyalkyl- or alkoxyaryl complexes
by alkylation 121. We have now investigated whether lithium
amides can be made t o react in the same manner.
Reaction of lithium diethylamide and hexacarbonylchromium
in ether affords a colorless, crystalline product which we
regard as a 1 : 1 adduct and which, according to its IH-NMR
spectrum, is coordinated t o approximately one molecule of
ether.
Compound ( I ) is a stable colorless liquid (b.p. 204'C/748
torr), whose composition has been confirmed by elemental
analysis and cryoscopic molecular-weight determination (calc.
293.67; found 304) in benzene. The IH-NMR spectrum
contains only one signal at 8 = --0.15 ppm (TMS as external
standard).
Mass spectrum (relative intensities): molecufar ion
S[NSi(CH3)31; (3), Si(CH3); (loo), S[NSi(CH3)3]2NSi(CH,);
(25), S[NSi(CH3)&NSiHCH; (14), S[NSi(CH3)3]NSi(CH&
(6), NSNf (9,NS+ (5).
IR(cm-1): 72w, 175 w, 228s, 272s, 430w, 619s, 696s,
738 w, 758 w, 840 vs, 1260 vs, 1290 vs, 3000 vs.
Raman (cm-I): 97.5 dp, 130 pp, 175 dp, 212 dp, 230 dp,
257pp, 280p, 306dp, 533 p, 644p, 697p, 760p, 1005 p,
1127 p, 1262 p, 1290 p.
The I R spectrum (THF, LiF optics) of ( I ) contains four
V C ~ O
bands at 2034 m, 1939 w, 1897 vs, and 1870 s cm-J.
In the J H - N M R spectrum ([D,j]-acetone), the signals due t o
the OCzH5 protons appear at T = 6.6(q) and 8.9(t), and
S
at T = 7.45 (9) and 9.0 (t) in the
those of the N C ~ H protons
intensity ratio of approximately 1 : 1. The lithium salt ( I )
was ethylated with triethyloxonium tetrafluoroborate in
methylene chloride t o give ethoxydiethylaminocarbenepentacarbonylchromium(0) (2) as pale yellow crystals
(m.p. 29OC).
OLi
(CO)&r-C(
+
[(CZH~)@IBF,
N (C2H5)z
If the SN3 group is assumed to have a planar-trigonal structure (symmetry D3h), as is most probably the case, the double
bands at 1290 and 1260 cm-1 in the I R and at 1290 and 1262
cm-l in the Raman can be assigned t o a v3 mode, and the
strong, IR-inactive band at 1127 cm-1 t o a v1 mode.
Angew. Chem. internat. Edit. Vol. 9 (1970) / No. 4
309
The structure of (2) was determined from the mode of preparation, complete elemental analysis, and spectroscopic
findings. The I R spectrum (n-hexane, LiF optics) reveals
two CO stretching vibrations at 2057 m (A,) and 1927 cm-1
vs (Ai, El.
For an octahedral configuration of the complex, the Cr(C0)5
group should have approximately C4" symmetry and exhibit
three IR-active fundamental vibrations: two of class A1 and
one of class E. Since only two bands are actually observed, it
must be assumed that the E vibration and the second A1
vibration coincide [31.
The 1H-NMR spectrum (benzene) recorded at 25°C contains signals due to three different ethyl groups in the intensity ratio 1 : 1 : 7 . The two quartets at T = 6.29 and 7.10 are
slightly broadened as a result of quadrupole coupling with
the nitrogen atom and are therefore assigned to the NCHz
protons; the quartet corresponding to the OCH2 protons
appears at T = 5.49. The triplets due to the CH3 protons of
the three ethyl groups are seen at T = 8.96, 9.07, 9.25.
The positions of the V C ~ Obands show that the (d+p)x
back-donation Cr+Ccarbene in (2) can only be weak. The
electron deficiency at the Ccarbene atom must therefore be
cancelled mainly by way of ir-electron interactions with the
lone pairs of the two hetero atoms. The non-equivalence of
the N-ethyl groups further supports the high bond order of
the Ccarbene-N bond; that of the Ccarbene-O bond, however, must by considerably lower since the occurrence of only
one group of signals for the CzH5 group rules out the existence of stable cis-trans isomers.
A marked double-bond character o f t h e C-N bond in alkoxyaminocarbenes bonded to a metal was previously suspected
in the Hgz+ complexes, also o n the basis of non-equivalent
N-alkyl groups (IH-NMR) 141, and recently confirmed by
an X-ray structure determination of cis-ClzP(CzH5)3[51~ H
(the
P~C(OCZH~)NHC
~ Ccarbene-0 bonds in this
complex were also found to be considerably shorter than
expected for a C-0 single bond). The dipole moment of (2)
was determined as p 2 0 = 5.75 0.1 D in cyclohexane.
The mass spectrum of (2) provides independent proof of
its structure161: molecular ion at m / e 321; there follow five
peaks corresponding t o the stepwise loss of five CO
groups: the most intense peak at m / e 181 is due to the fragment C ~ C ( O C ~ H ~ ) N ( C Z H ~ ) ' .
Procedure:
All operations must be carried out in the absence of air and
in Nz-saturated, anhydrous solvents.
LiN(CzH5)z (10.0 mmoles) in ether (100 ml) is slowly added
dropwise to a n ice-cooled, stirred suspension of Cr(C0)6
(2.2 g, 10.0 mmoles) in ether (200 ml). The yellow solution is
concentrated to a volume of about 50 ml and filtered, and
( I ) is precipitated by addition of n-hexane. T o a stirred,
ice-cooled suspension of ( I ) (1.86 g, 5.0 mmoles) in methylene chloride (25 ml) is added portionwise a solution of
[(CzH5)30]BF4 (0.95 g, 5.0 mmoles) in methylene chloride
(25 ml). After removal of solvent the yellowish-brown, oily
residue is extracted with two 20-ml portions of n-hexane, the
extract is concentrated to a volume of 10 ml and filtered, and
(2) is precipitated by cooling to -50 'C. The crystals can be
sublimed at 30 "C in a high vacuum; yield about 20% [based
on cr(co)6].
Received: February 17, 1970
[ Z 168 IE]
141 (I. Schollkopf and F. Gerhart, Angew. Chem. 79, 578
(1967); Angew. Chem. internat. Edit. 6 , 560 (1967).
[ 5 ] E. M . Badlev, J . Chart, R . L . Richards, and G. A . Sim,
Chem. Commun. 1969, 1322.
[6] Atlas CH 4; ion source TO 4 . Measurements performed by
Dr. .
I
Miiller.
.
Miinchen.
Novel Radicals from the Reaction of Phospholes
with Potassium
By Colin Thoinson and D . Kilcnst [*I
During the investigation of the room temperature and low
temperature reactions of various substituted phospholes ( I )
with potassium in dimethoxyethane (DME) and tetrahydrofuran (THF), anomalous ESR signals have been observed,
similar to those found in the reduction of benzene with
Na-K alloy in DME/THF[l-31.
R43-JR3
R5
p
R2
The reaction of ( l a ) (with RL = phenyl) with potassium in
D M E at room temperature has been found to proceed as
follows 141:
We have observed three strong, distinct and interconvertible
signals during the reduction of 1,2,5-triphenylphosphole
( I b ) , and of pentaphenylphosphole ( l c ) with potassium,
both in D M E and in THF.
Signal A consists of a 1 : 2 : 1 triplet (aH = 6.1 gauss) split
into a 1 : 4 : 6 : 4 : 1 quintet (UH = 1.7 gauss); the signal
contour corresponds to a 15 line spectrum already mentioned
several times in the literature"-31. Under high resolution and
low microwave power level, each line is split further into
approximately 12 lines (separation about 0.13 gauss; cf. [ 3 9 .
Signal B consists of a doublet (aH = 6.3 gauss) split into
seven or nine lines ( U H = 1.7 gauss; cf. Fig. 1). As with A,
further resolution is observed at low powers, but varying
linewidths make the number of additional lines uncertain,
although the separation is about 0.14 gauss.
5G
%-+
German version: Angew. Chem. 82, 325 (1970)
[*I Prof. Dr. E. 0. Fischer and Dipl.-Chem. H. J. Kollmeier
Anorganisch-Chemisches Laboratorium
der Technischen Hochschule
8 Miinchen 2, Arcisstrasse 21 (Germany)
[I] Carbene Complexes of Transition Metals, Part 22. - Part
21: E. 0. Fischer and V . Kiener, J. organometallic Chem., in
press.
[ 2 ] E. 0. Fischer and A . Maasbol, Chem. Ber. 100,2245 (1967);
R . Aumann and E. 0 . Fischer, ibid. 101, 954 (1968).
[3] F. A . Cotton and C . S . Kruihanzel, J. Amer. chem. SOC.84,
4432 (1962).
310
m
Fig. I . ESR spectrum "B", from pentaphenylphosphole with potassium in T H F a t 25 "C. (Moderate resolution.)
Angew. Chem. internat. Edit.
/ Vol. 9 (1970) J No.
4
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