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Molecular Structure of [Mn(CO)4NSOF2]2Ч A Dinuclear Transition Metal Complex Containing Difluorooxosulfimidato Bridges.

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lylation of alkynes is one of the most straightforward routes
to these compounds, but the product is often accompanied
by 1,2-disilylethanes['~.Condensation between a hydrosilane
and a haloethene requires drastic conditions['I, while treatment
of vinylic Grignard reagents with chlorosilanes requires solvents such as ether, THF, or HMPA to promote the reaction[3!
We have found that vinylsilanes and vinylenebissilanes can
be conveniently prepared by the reaction between a disilane
and a haloethene in the presence of a homogeneous palladium(0) catalyst. Vinylsilanes (3) (Table 1) were prepared
by heating a mixture of a chloro(methy1)disilane (1)[41, a
haloethene ( 2 ) , and tetrakis(tripheny1phosphane)pallad i u m ( ~ ) [as
~ ]catalyst in a sealed reaction vessel or an open
apparatus. Thus Pdo-catalyzed reaction of (E)-l,2-dichloroethene ( 4 ) with two equivalents of (1) gives vinylenebissilane
( 5 ) (Table 1).
C13-" Me,Si-SiMe "C13-"
+
R\
/
H
(laj, n = 1
(Ib), n = 2
H
/C =C,
__+
X
Pd
(.?a). R = H, X = C 1
(2b), R
= Ph, X = Br
CI3-" MenSi-CH=CH-SiMe,Cl3-,
+
2 Me,SiCl+,
( 5 a l . (56)
Table 1. Vinylsilanes (3) and vinylenebissilanes ( 5 ) prepared
R
n
X
Yield [ %] [a]
E :Z
H
H
1
2
1
2
1
2
CI
CI
Br
Br
45
56
85 (76)
83 (72)
86
80 (50)
9.1
9:1
~~
(3a)
(3b)
(3c)
(3d)
Ph
Ph
(5al
(5b)
Received: February 1, 1978 [ Z 930 IE]
German version: Angew. Chem. YO, 288 (1978)
CAS Registry numbers:
( 1 a ) , 4518-98-3; ( I b ) , 4342-61-4; ( 2 ~ ) 75-01-4;
.
( Z b ) , 588-72-7; ( 3 a ) ,
124-70-9; ( 3 b ) , 1719-58-0; ( 3 c ) , 17902-47-5; ( 3 d ) , 61518-55-6; ( 4 ) , 156-60-5;
( E ) - ( S a ) , 65899-10-7; (Z)-(Sa), 65899-09-4; ( E ) - ( 5 b ) , 65899-08-3; (Z)-(Sh),
65899-07-2
[l] C. Earbon, R . W Bott in A. G. MacDiarmid: Organometallic Compounds
of the Group IV Elements. Vol. 1. Marcel Dekker, New York 1968,
p. 269.
[2] A. D. Petroo, B. F . Mironoc, I! A. Ponomarenko, E. A. Chernyshev:
Synthesis of Organosilicon Monomers. Consultants Bureau, New York
1964, p. 128.
[3] S. D. Resenberg, J . J . Walburn, 7: D . Stankovich, A. E. B a h t , H . E.
Ramsden, J. Org. Chem. 22, 1200 (1957); D. Seyferrh, L. G . Vaughan,
R. Suzuki, J. Organometal. Chem. 1 , 437 (1964); J . DonoguPs, J.-P.
Pillot, N . Duffaut, R . Calas, C. R. Acad. Sci. C 278, 467 (1974).
[4] H. Watanabe, N . Kobayashi, E Koike, S . Nagashima, H . Matsumoto,
Y. Nagai, J. Organomet. Chem. 128, 173(1977); H. Matsumoto, 7: Moregi,
M . Hasegawa, E Nagai, ibid. 142, 149 (1977).
[ 5 ] H. Matsumoto, S . Nagashima, K . Yoshihiro, E Nagai, J. Organometal.
Chem. 85, C 1 (1975); D . Azuriun, S.S. Dua, C . Eurbon, D . R . M . Waltone,
ibid. 117, C 5 5 (1976); H . Matsumoto, K . Yoshihiro, S . Nagashima, E
Nagai. rbid. 128, 409 (1977); H . Marsumoto, T Yako. S . Nagashima,
7: Motrgi, E Nugai, ihid., in press.
Molecular Structure of [Mn(C0)4NSOF2]2A Dinuclear Transition Metal Complex Containing
Difluorooxosulfimidato Bridges[**]
(41
Cpd.
( Z ) - ( 5 b ) : 'H-NMR (cc14)6 ~ 0 . 5 6(s, 12H), 6.82 (s, 2H);
IR (neat) 2950, 1405, 1255,925,840,810,800,695, 650cm-';
mass spectrum (70eV): m/e=212 (M').
By Bruno Buss, Dieter Altena, Rudiger Mews, and Oskar
Glemser[*]
Preliminary studies on the dimeric species [M(CO),NSOF,], with M=Mn, Re ans NSOF, groups as bridging
ligands failed to establish whether the metal atoms are linked
via nitrogen-sulfur-oxygen bridges or only by the nitrogen
atoms of the F,S(O)=N ligands"]. In the last-mentioned
case, these complexes should possess a structure analogous
to [Mn(C0)4Br]2['1. The donor strength of the ligand and
the effect of coordination on the NS bond also remain to
be established.
_____
[a] Yields determined by GLC; isolated yields given in parentheses.
The hitherto unknown vinylenebissilane ( 5 b ) is expected
to be a precursor of novel siloxane polymers.
Experimental
Synthesis of ( 3 c ) : A mixture of ( l a ) (8.39g, 42mmol),
(E)-(2b) (7.35 g, 40mmol), and Pdo catalyst (0.24g, 0.2 mmol)
is refluxed under nitrogen for 1 h with stirring. The mixture
is diluted with n-pentane (40 ml) and the precipitated catalyst
filtered off. Evaporation of low boiling materials and subsequent distillation gives (E)-(3c) (6 g) in 99 % purity. The product was identified by its 'H-NMR, IR, and mass spectrum.
Synthesis of ( 5 b ) : ( 4 ) (32g, 340mmol), ( 1 b ) (131 g,
700 mmol), and the palladium(0) catalyst (1.16 g, 1.O mmol)
were introduced into a stainless steel vessel. The vessel was
flushed with nitrogen, sealed and heated at 180°C for 15h.
Work-up gave 36g of (E)- and (Z)-(5b ) (9 : 1) in 98 % purity
as a colorless liquid. (E)-(5b): 'H-NMR (Ccl4) 6=0.56 (s,
12H), 6.77 (s, 2H); IR (neat) 2950, 1405, 1255, IOOO, 840,
815, 790, 650cm-'; mass spectrum (70eV): m/e=212 (M+).
280
N-Mn-N' 7 6 4 "
Mn-N-Mn' 103 5"
Mn-N-S
1282"
h-
F i l l - S - F I 2 I 906"
F-S-0
105 8" 191
Fig. 1. Molecular structure of the dinuclear manganese complex [Mn(CO)4NSOF,], with principal bond lengths [A] and angles
["I.
I*] Prof.
Dr. 0. Glemser, Dr. B. Buss, Dr. D. Altena, Priv.-Doz. Dr. R.
Mews
Anorganisch-chemisches Institut der Universitat
Tammannstrasse 4, D-3400 Gottingen (Germany)
[**I
This work was supported by the Deutsche Forschungsgemeinschaft.
Angew. Chem. I n t . Ed. Engl. I7 ( I 9 7 8 ) N o . 4
An X-ray structure analysisL31of the manganese complex
has now shown the isolated molecule to contain two octahedral
units joined by a shared edge (cf. Fig. 1).
The central moiety containing the Mn, N, and S atoms
is almost planar, while the MnzNz four-membered ring is
exactly planar, showing that the nitrogen atoms no longer
possess a stereochemically effective lone pair. All the Mn-N
distances are equal within the limits of error and somewhat
longer than would correspond to a single bond (based on
the covalent radius of 1.398, for MnoL4]).Both the Mn...Mn'
distance of 3.318(2)8, and the angle in the central portion
of the molecule show that no direct metal-metal bond is
present; the small N-Mn-N'
angle (76") even suggests a
repulsive interaction between the two Mn atoms.
The NSOFZgroup serving as bridge has a strongly distorted
tetrahedral symmetry. The S-0 and S-F bond lengths closely resemble those in other compounds R-NSOF,['].
The
very short N-S bond of 1.434(6) 8, corresponds to a bond
order of ca. 2.S6] and indicates strong d,-p, bonds between
sulfur and nitrogen; it is ca. 0.05 8, shorter than in CINSOFz[sal
and-within the limits of error-of the same length as in
(CO)sReNSOFz[5b1.The NSOFz groups of [Mn(C0)4NSOFz], can be formally regarded as four-electron donors
[cf. ( I a ) ] , and in the compounds R-NSOFz with R=C1
and Re(C0)5 as two-electron donors. However, the surprisingly large Re-N-S
angle of 140" in (CO)5ReNSOF2suggests a bonding contribution from the nitrogen lone pair;
in CINSOFz, on the other hand, the lone pair is fully effective
(Cl-N-S:
114")'sa1.
There are two possible ways of describing the bonding:
the manganese atoms have the oxidation number + 1 in (1 a)
and 0 in ( 1 b), the NSOF2 group being considered as a fouror three-electron donor. No decision in favor of either of
these two alternatives is possible on the basis of available
experimental evidence.
The bonds of the CO ligands correspond to those in other
carbonyl complexes[71;nevertheless, the trans effect (MnC,, = 1.807A, Mn-C,, = 1.8998,) is relatively pronounced.
[7] Cf., e.g., R . Bau, S. W Kirtley, 7: N . Sorrell, S . Winarko, J. Am. Chem.
SOC.96, 988 (1974); S. J . La Placa, W C. Hamilton, J . A. Ibers, A.
Davison, Inorg. Chem. 8 , 1928 (1969); references cited therein.
N,N-Dichlorourethane-A Selective Chlorination Reagent; Synthesis of Corticoids
By Yehuda Mazur and Zvi Cohen"]
Continuing our studies on the selective functionalization
of steroid molecules['], we searched for a simple method to
introduce a functional group at C I 1 in deoxycorticoids, to
replace the microbiological method commonly used for this
purpose.
We have now found that saturated steroids can be selectively
chlorinated with N,N-dichlorourethane (DCU).
DCU is a stable, distillable, but highly reactive pseudohalogen which is easily prepared by reacting urethane with chlorine[']. This compound was found by Ch~brieu'~]
to add to
olefins, giving the unstable N-chloro-N-(P-chloroalky1)carbamates, which can be readily reduced to the d-(P-chloroalky1)carbamates. We observed that cyclohexane on exposure to
light in the presence of DCU is converted into chlorocyclohexane and urethane and that benzene solutions of adamantane
and DCU on irradiation with a sunlamp gave t-chloroadamantane in high yields. Reaction of DCU with steroids resulted
mainly in chlorination at C-9: androstane-3P,17P-diyl diacetate was converted into a mixture of tertiary chlorides, which
after dehydrochlorination with AgC104 gave the corresponding 9(11)- and 14-androstene derivatives in 40 and 9 % yield,
re~pectively[~I.
In the case of steroids with dihydroxyacetone
side chains, DCU proved to be even more selective. We have
chosen (1 a ) and ( 2 a ) as starting compounds; these compounds are intermediates in the preparation of the medically
useful 16a- and 16P-methyl~orticoids['~.
LOAC
Received: September 26, 1977;
revised: February 6, 1978 [Z 929 IE]
German version: Angew. Chem. 90, 287 (1978)
CAS Registry numbers:
[Mn(CO)dNSOF,] 2r 659 15-49-3
_____
[l] R. Mews, 0. Glemser, J. Chem. SOC.Chem. Commun. 1973, 823.
[2] L. F . Dahl, C. H . Wei, Acta Crystallogr. 16, 611 (1963).
[3] 1050 independent diffractometer data, solution by conventional methods,
refined with anisotropic temperature factors to R=7.1 %; space group
P2,/n (standard formulation P2,/c-C:,,, No. 14), Z = 2; lattice constants
(20°C): a=1002.4(5), b=1175.1(5), c=736.8(4)pm, ,9=100.96(4)",
d,,,, =2.08, d,,, =2.1Og
[4] F. A. Cotron, D . C. Richardson, Inorg. Chem. 5 , 1851 (1966).
[5] a) H . Oberhammer, 0.Glemser, H . Kliiuer, Z. Naturforsch. A 2 9 , 901
(1974); b) B. Buss, D. Altena, to be published.
[6] 0 . Glemser, A. Miiller, D. Bohler, B. Krebs, Z . Anorg. Allg. Chem. 357,
184 (1968).
Angew. Chem. lnt. E d . Engl. 17 ( 1 9 7 8 ) No. 4
[*] Prof. Dr. Yehuda Mazur, Zvi Cohen
Department of Organic Chemistry, The Weizmann Institute of Science
Rehovot (Israel)
281
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dinuclear, structure, complex, containing, molecular, metali, bridge, transitional, difluorooxosulfimidato, 4nsof2
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