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cis-2-Telluro-1 3 25 43-diazadiphosphetidineЧA Fluxional Redox System.

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up in 20ml ether. The filtered red-brown solution is stirred
under 1 bar Nz,whereupon its color changes within a few
minutes to orange-red. After 2 h the reaction mixture is filtered
and slowly cooled to -78°C. The solution is decanted off
and the orange-red crystals dried at 2OoC/0.l torr. Yield of
(2): 450mg (85 %).-IR: v(NN): 1795 vs (br) and 1758 m
(br) cm-' (Nujol mull); v(NN): 1868 vs (br) and 1843 m
(br) cm-' (THF). Conductivity of (2) (0.25 M in THF, 2 0 T ,
1 bar Nz): ~ < 1 0 R
- -~' cm-'.
The site-exchange of the tellurium is fast on the NMR
time
but can be perceptibly slowed down by lowering
the temperature. Compound ( 3 ) forms pale yellow crystals
(softening 77-83 "C, melting range 83-90°C) which dissolve
very well in ether and methylene chloride, readily in benzene
Received: May 20, 1977 [Z 745 I€]
German version: Angew. Chem. 89,499 (1977)
CAS Registry numbers:
K[(Me3P)3Co(propene)], 63181-07-7; K[(Me~P),Co(cyclopentene)], 6318108-8; (2), 63181-09-9; ( 3 ) , 63181-11-3: (Me3P)3CoCI,53432-06-7
a) R . Hammer, H.-F. Klrin, U . Schubert.
A. Frank, C . Hurrner, Angew.
Chem. 88, 648 (1976); Angew. Chem. Int. Ed. Engl. 15, 612 (1976);
b) K . Jonas, hid. 85, 1050 (1973) and 12, 997 (1973); C. Kriiger, Y-H.
Guy, ;bid 85, 1051 (1973) and I Z , 998 (1973). K . Jqnas, D . J . Bruurr.
C . Kruger, P . J . Roberts, Y-H. Tyay, J. Am. Chem. Soc. 98, 74 (1976);
c) M. Mercer, R. H . Crabtree, R . L. Richards. J. Chem. Soc. Chem.
Commun. 1973, 808.
Dinitrogencobaltates NaN2Co(PR3), were first described by M . Aresta,
C . F. Nobile, M . Ross;, A . Sac.ro, Chem. Commun. 1971, 781.
R . Hummer, H:F. Klein, unpublished.
u=2767.3, b=1627.4, c=2802.5pm, p = l 15.94"; d,,,,=1.25g/cm3. Data
collection with a Syntex-P2, diffractometer: solution of structure (2639
independent reflections. R , = 0.085) with Syntex-XTL.
A. F. PVells: Strucrural Inorganic Chemistry. 3rd Ed. Clarendon Press,
Oxford 1962, pp. 761 R
H.-F. Klein, H . H. Kursch, Inorg. Chem. 14, 473 (1975).
or toluene, and modestly in pentane. Elemental analysis, mass
spectrum [16eV: m/e=362 (50% M+), 178 (IOO)], molecular
weight determination (378, cryoscopic in benzene), and a crystal structure analysis['] confirm the composition and structure
of the molecule, which is monomeric both in solution and
in the solid state.
Procedure
Tellurium (0.67g, 5.25 mmol) is added to an ice-cooled (cu.
6°C) stirred solution of (2)"' (1.2 g, 5.12 mmol) in benzene
(1 6ml).After 3 hat room temperature, excess tellurium is filtered
off (G4 frit), the solvent is drawn off and the product (3)
dried under oil-pump vacuum; yield quantitative.
Received: May 24, 1977 [Z 747 IE]
German version: Angew. Chem. 89,500 (1977)
CAS Registry numbers:
(21,63104-58-5: (J), 63104.59-6
cis-2-Telluro-l,3,2h5,4h3-diazadiphosphetidineA Fluxional Redox System
By Otto J . Scherer and Giinter Schnubl[*]
Judicious choice of X and Y and ofthe other ligands attached
to the two P atoms in the phosphorus-chalcogen compounds
( I ) [e.g. X=O, S; Y=O, S, (CH2)", NR] known in such
great variety should permit preparation of a fluxional redox
system in which X undergoes reversible intramolecular shift.
Conditions for the study ofsuch a process are ideally fulfilled
by cis-1,3,2h3,4h3-diazadiphosphetidine(2)['], whose 1 : 1
reaction with
yields cis-l,3-dimethyl-2,4-di-tertbutyl-2-telluro-l,3,2h5,4h3-diazadiphosphetidine
(3 ).
[l] 0. J . Scherer, G . Schnubl, Angew. Chem. 88, 845 (1976); Angew. Chem.
Int. Ed. Engl. 13, 772 (1976).
[2] (is-[RP(Te)NCH3I2 can also be synthesized.
[3] Examples: a) K . J . Iryolic. The Organic Chemistry of Tellurium. Gordon
and Breach, New York 1974. p. 256; h) 0. J . Scherer, G . Sehnabl, Chem.
Ber. 109, 2996 (1976): c) W-W Du Monr, H.-J. Kroth, J. Organomet.
Chem. 113, C 3 5 (1976); d ) D. H . Brown, R. J . Cross, D. Millmgron,
hid. 125, 219 (1977); the rollowing fast equilibria R , P T e + R j P s
RjPTe+R,P and R3PTe+R3P+Te were first mentioned in [3c] and
[3d] (tellurium shift probably bimolecular).
Compound ( 3 ) can be stored at room temperature for several weeks,
r.g. in benzene solution, and for several months in crystalline form
(sealed flask, daylight).
'H-NMR spectrum (cu. 15 "/, in CH2C12,TMS int., 35°C): 6CH3C= 1.12
(d), , J P H = 16.9 Hz: 6CH3N=2.56 (t), 3 J p ~ =13.7Hz. -50°C: GCH3C
(>L3P)=l.13(d), ,JpH=13.7 Hz: 6CH3C (hSP)=1.12 (d), 3 J p H = 1 9 . 9 Hz;
GCH3N=2.49 (dd), 3./j.3pH= 10.7, ' J J A ~ P H = I ~ . ~ H
"P['H)-NMR
z.
spectrum(cu. 15 : b i n CH2C12, 85 "/, H3PO4 ext., -60°C): 6(A3P)=200.4
(d), 6(h5P)=119.5 (d), 'Jpp= 1 8 . 0 H ~ .
The concentration dependence of the coalescence temperature (T,:
-3O0Cfora35%solutionand :
- I0"Cfor a3.5% so1ution)measurable
at higher dilutions show that both an intramolecular and an intermolecular exchange can occur. Formation of a mixture of (2) and ci.s
[RP(Te)NCH3]2 conceivable in the latter case can be detected neither
in the ' H - nor in the 3 ' P low-temperature NMR spectrum.
Dr. S. Pohl, Bielefeld, personal communication.
Synthesis of a Secondary Aminophosphane['l
Unlike the few known phosphorus-tellurium compounds
of similar kindI'1, compound ( 3 ) is exceptionally stable141.
Temperature dependent H- and 31P-NMR studies[51 show
(3) to have dynamic behavior.
By Edgar Nircke and Gerhard Ringel[*]
Aminoiminophosphanes, phosphorus-nitrogen compounds
containing a strongly polar 3p,(Pk2pn(N) bond (1 ), undergo
addition with proton donors to give aminophosphanes ( 2 a )
and the tautomeric iminophosphoranes (2 b)lz1.
~-~
[*] Prof. Dr. 0.
J. Scherer, Dr. G. Schnabl
Fachbereich Chemie der UniversitPt
Pfaffenbergstrasse 95, D-6750 Kaiserslautern (Germany)
486
[*] Priv.-Doz. Dr E. Niecke, Dipl.-Chem. G . Ringel
Anorganisch-chemisches lnstitut der Universitat
Tammdnnstrasse 4. D-3400 Gottingen (Germany)
Angew. Chrm.
/or. E d . Engl. 16 ( 1 9 7 7 ) N o . 7
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diazadiphosphetidineчa, telluro, redox, fluxional, system, cis
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