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Octaphenyl-1 5 25 3 45 65 7 85-diazahexaphosphocine.

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is a suitable model to check theoretical predictions about
1,4-additionsr21and to examine proposals on the two-step
mechanism of certain carbene additions.[81It is obvious
that 1 , a 1,3-diene with normal 1,4-reactivity but greatly reduced 1,2-reactivity, may also be used as a mechanistic
probe for other reactions in which 1,3-dienes usually
participate as .2-units.
Received: March 4, 1985; [Z 1201 IE]
German version: Angew. Chem. 97 (1985) 567
111 R. A. Moss, M. Jones, Jr. in R. A. Moss, M. Jones, Jr. (Ed.): Reactiue Intermediates, Vol. 2, Wiley, New York 1981, Chap. 3.
[2] a) H. Fujimoto, R. Hoffmann, J. Phys. Chem. 78 (1974) 1167; b) W. W.
Schoeller, E. Yurtsever, J. Am. Chem. SOC. 100 (1978) 7548: W. W.
Schoeller, N. Aktekin, J. Chem. SOC.Chern. Commun. 1982, 2 0 ; c) for another interpretation: N. L. Bauld, D. Wirth, J. Comput. Chem. 2 (1981)
the composition (thf),LiP,,.[" The oxidation product 2
can be isolated from the reaction solution as analytically
pure crystals.
The corresponding reaction (2) with lithium bis(dipheny1phosphino)amide 3['] proceeds rapidly enough even
without the aid of TMEDA and leads to formation of the
lithium salt 4 containing a seven-membered anion; 4 is
again a lithium phosphinoamide and therefore reacts further in a second step (3) with white phosphorus to give the
eight-membered ring 5 =A, n = 2.15]The reaction cannot be
stopped just at the stage of the intermediate product 4,
even by a high 3/P4 ratio (7 :2). For the polyphosphide
precipitate, the reaction stoichiometry gives a Li/P ratio of
1 : 8 corresponding to LizP,6;[41excess P4 remains unchanged.
131 a) C. W. Jefford, nT. Kabengele, J. Kovacs, U. Burger, Helv. Chim. Acra
57 (1974) 104: for more recent work see [ l ] : b) U. Burger, G. Gandillon,
Tetrahedron Lerr. 1979. 4281.
141 a) H. Hart, J. W. Raggon, Tetrahedron Lett. 24 (1983) 4891; L. W. Jenneskens, F. J. J. d e Kanter, L. A. M. Turkenburg, H. J. R . d e Boer, W. H.
d e Wolf, F. Bickelhaupt, Tetrahedron 40 (1984) 4401; b) L. A. M. Turkenburg, W. H. d e Wolf, F. Bickelhaupt, Tetrahedron Lett. 23 (1982) 769; see
also L. W. Jenneskens, W. H. de Wolf, F. Bickelhaupt, Angew. Chem. 97
(1985) 568; Angew. Chem. Int. Ed. Engl. 24 (1985) 585.
[S] H. Klein, H. Mayr, Angew. Chem. 93 (1981) 1069: Angew. Chem. Int. Ed.
Engl. 20 (1981) 1027.
[6] ' H N M R (CDCI,): 2a: 6=0.86, 0.90, 1.00, 1.06 (doubled int.), 1.15 ( 5 s :
CH,), 1.53 (s; CH2), 4.64, 5.04 (2s; vinyl-H); 2b: 6=0.85,0.91, 1.06, 1.10
(doubled int.), 1.17 ( 5 s : CH,), 1.70 (s; CH2), 4.60, 5.08 (2s; vinyl-H); 3a:
2CH2); 3 b : 6 = 0 , 8 6 ( ~ ; 2 C H , ) ,
0.95 (s; 4CH3), 3.38 (s; 2CH2).
171 D. Seyferth, Ace. Chem. Res. 5 (1972) 65.
[8] E. V. Dehmlow, R. Kramer, Angew. Chem. 96 (1984) 700; Angew. Chem
Int. Ed. Engl. 23 (1984) 706; B. Giese, W.-B. Lee, C. Neumann, ibid. 94
(1982) 320 and 21 (1982) 310.
2 Li+
ph\ P /
/ \P
hexaphosphocine* *
By Arfred Schmidpeter* and Giinther Burget
Dedicated to Professor Rorf Huisgen on the occasion of
his 65th birthday
Two-coordinated nitrogen in organic aromatic heterocycles such as pyridine or the azoles can be replaced by twocoordinate phosphorus with retention of the bonding system. We now wanted to know whether this exchange is
also possible in the case of inorganic ring systems with delocalized double bonds, such as cyclotetraphosphazenes;
that is, whether compounds of the series A can be prepared.
Nucleophilic P4-degradation analogous to that with alkali metal phosphinited'l was considered a promising synthetic strategy. Thus, for example, lithium diphenylphosphinoanilide 1 also effects the disproportionation of white
phosphorus according to equation (1) on boiling under reflux in tetrahydrofuran (THF). Tetramethylethylenediamine (TMEDA) accelerates the reaction. According to the
reaction stoichiometry and C,H-analysis, the insoluble
black polyphosphide that separates during the reaction has
Prof. Dr. A. Schmidpeter, DipLChem. G. Burget
Institut fur Anorganische Chemie der Universitat
Meiserstrane I, D-8000 Munchen 2 (FRG)
Phosphazenes, Part 78. This work was supported by the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen 1ndustrie.-Part
77: A. Schmidpeter, M. Nayibi, P. Mayer, T. Tautz, Chem. Ber. 116
(1983) 1468.
0 VCH VerlagsgesellschaJi mbH. 0-6940 Weinheim, I985
An iterative spectral analysis confirms the spin-system
AA'A"A"'MM' of 5 , but does not allow a satisfactorily accurate enough determination of the remaining coupling
constants. The "P-upfield shift and PP coupling constant
correspond to those in anionic"] and cationicL6Isystems
consisting of a central twofold coordinated phosphorus
atom and two tetrahedrally coordinated phosphorus
atoms. 5 is thermally stable up to at least 200°C. In hydrous THF, 5 hydrolyzes within a few days with formation
of (Ph2P),NH. It is slowly degraded by Li+Ph,PO- at
60"C, reforming 4 and 3 and yielding the salt 6."] Like the
crystals of many cycloph~sphazenes,[~~
those of 5 also incorporate solvent molecules.
Attempts to prepare the end member of the series of
compounds A , namely 9 with n = 4, remained unsuccessful. It is thermodynamically less stable than the mixture of
tetraphenyldiphosphane 10 and P4. Formally, 9 could be
formed by disproportion of P4 with the nucleophile lithium
diphenylphosphide 7 according to equation (4). Indeed,
the reaction does proceed in the desired direction but only
u p to the first (corresponding to 3 ) stage 8.[81Compound 8
does not formally take u p P + from further P4 (Sfits), but
gives u p P- to P4 according to equation (5). The reaction
proceeds the same with sodium or potassium salts instead
of lithium salts.[81
A hexaphosphocine 12, in which the two nitrogen members of 5 are replaced by NCC members in the sense of the
cyano-displacement principle, could be detected in the
OS70-0833~8S/0707-0580$ 02.50/0
Angew. Chem. Int. Ed. Engl. 24 (1985) No. 7
A Macrobicyclic Receptor Molecule
for the Diquat Dieation**
x/4 p4
2 Li+PhzP-
Li+[Ph,P-P-PPh,]- Lip,-,
x/4 p,
By Billy L. Allwood, Franz H . Kohnke,
J. Fraser Stoddart, * and David J. Williams*
Recently, we have demonstrated”] that, although the macrobicyclic receptor molecule 6 provides enhanced complexation of the diquat dication ([Diquat]’+) relative to
that exhibited by dibenzo-[30]crown-l0, 1 ,[’I and its derivatives 2-4,[31 its [DiquatI2+ receptor site is larger than is
necessary for a good supramolecular match. In view of the
biological significance of [Diquat]’ , and its relevance and
importance in redox processes and photochemical syst e m ~ , synthetic
modifications of 6, so as to achieve an
improved receptor molecule, constitute one of our prime
reaction (6) of lithium cyanobis(dipheny1phosphino)methanide 11 19] with [18]crown-6-potassium dicyanophosphide“”’ (not with P4), but could not be isolated.
[(Ph,P),CCN]2 [18]crow1-6-K+ [P(CN)p]-
- 2
Li+ CN-
-2 [ 18]crown-6-K*
Ph- P /’*P
- Ph
/ ‘P
Experimental procedure and physical data
2 : A vigorously stirred mixture of 1 (40 mmol) and P4 (9.91 g, 80 mmol) in
T H F (100 mL) was heated under reflux for 24 h. A black precipitate separated from the orange-red solution; it was separated from the hot reaction
mixture by filtration on a fnt and washed with THF. The filtrate and washings were evaporated down to 80 mL and diluted with 80 mL of n-hexane. A
colorless, crystalline precipitate of 2 . T H F separated out; this was recovered
by filtration and washed with n-hexane (yield: 5.70 g (43%). ” P NMR (THF/
TMEDA): AZM, 6(A)=+31.7,6(M)= -119.6,J(AM)=410 Hz.
4 : ” P NMR (THF): A2B2M, &(A)= +45.7, 6(B, terminal)= +49.6, S(M)=
- 122.5, J(AM)=410, J(AB)=68 Hz.
5 : A vigorously stirred mixture of 3 (11.74g, 30 mmol) and P4 (8.43 g,
68 mmol) in T H F (200 mL) was heated under reflux for 24 h. The solution
turned deep-red in color and a violet-black precipitate separated out. The hot
solution was filtered on a frit and the precipitate was washed with THF. On
cooling the filtrate and washings to room temperature, 5 . T H F separated out
as light yellow, fine needle-like crystals (first fraction); after filtration, the filtrate was evaporated down to 100 mL and treated with 100 mL of n-hexane.
This provided a second crop of 5 . T H F . Total yield of 5 . T H F (m.p. 220°C
(dec.)):65%;”PNMR(THF):AA‘A”A”’MM’,&(A)=+35.0,6(M)= -141.5,
J(AM)=429 Hr. O n using benzonitrile, crystals of 5.C6H5CN having the
same appearance were obtained.
12: “P-NMR (THF): AA‘A”A”’MM‘, 6(A)=36.3, &(M)= - 141.2, J(AM)=
425 Hz.
Received: March 8, 1985;
revised: April 23, 1985 [Z 1208 IE]
German version: Angew. Chem. 97 (1985) 602
CAS Registry numbers:
1, 96688-80-1; 2, 96688-81-2; 3, 73785-70-3; 4, 96688-82-3: 5, 96688-83-4;
11, 96688-84-5; 12, 96688-85-6; [18]crown-6-K+[P(CN),] -, 8 1043-01-8; P4,
( I ] A. Schmidpeter, G. Burget, H. G . von Schnering, D. Weber, Angew.
Chem. 96 (1984) 795; Angew. Chem. 1111.Ed. Engl. 23 (1984) 816.
[2] Cf. (thf).,LiP,;: G. Fritz, J. Harer, K. Stoll, T. Vaahs, Phosphorus Sulfur
I8 (1983) 65.
131 J. Ellermann, M. Lietz, 2. Nottrrforsch. 8 3 5 (1980) 64.
[4] M. Baudler, 0. Exner, Chem. Ber. 116 (1983) 1268.
[5] Two other cases of replacement of the N atoms of Ph8P4N4by isoelectronic groups have been reported: N/O +-exchange: A. Schmidpeter, K.
Stoll, Angew. Chem. 83 (1971) 142; Angew. Chem. I n f . Ed. Engl. 10
(1971) 13 I ; double N/GaEt,-exchange: H. Schmidbaur, S. Lauteschlager, B. Milewski-Marhla, Chem. Ber. 116 (1983) 1403.
[6] A. Schmidpeter, S. Lochschmidt, W. S. Sheldrick, Angew. Chem. 97
(1985) 214; Angew. Chem. Inr. Ed. Engl. 24 (1985) 226.
[7] H. R. Allcock: Phosphorus-Nitrogen Compounds, Academic Press, New
York 1972, p. 238.
[8] A. Schmidpeter, G. Burget, Phosphorus Sulfur 22 (1985) 323.
191 Prepared from (Ph2P)2CHCN (H. Schmidbaur, T. Costa, private communication) and n-butyllithium.
[lo] A. Schmidpeter, G. Burget, F. Zwaschka, W. S. Sheldrick, 2. Anorg. Allg.
Chem 527 (1985), in press.
Angen. Chem. In!. Ed. Engl 24 (1985) No. 7
R I H C&
We (1) describe here the synthesis[’] of the macrobicyclic
receptor molecule 7 from 5, (2) report on ‘H-NMR spectroscopic investigations in solution (Fig. 1, Table I), designed to probe the kinetics and thermodynamics of its
complexation with diquat bishexafluorophosphatef6I in relation to its conformational behavior and mode of binding
(Fig. 2), and (3) provide, from X-ray crystallographic investigations, details of the solid-state structures of both the
free (i.e., 7 ) and complexed ([Diquat]’+) statesl5.’I (Fig. 3
and 4).
At room temperature in the ‘H-NMR spectrum of [Diquat. 7][PF6I2recorded[’] at 400 MHz in [D,]acetone, all the
signals for the diquat and O-rnethylene protons are very
broad. On cooling the solution, the spectrum becomes well
resolved, until, by -20°C (Fig. l), all eight bipyridinium
protons and two sets of N-methylene protons in the complexed [Diquat]’+ can be identified as separate signals in
addition to the AB system arising from the benzylic methylene protons of 7. Analyses of the temperature-dependent
spectra afforded the kinetic and thermodynamic data
listed in Table 1 for the processes illustrated in Figure 2:
[*I Dr. J. F. Stoddart, F. H. Kohnke
Department of Chemistry, The University
Sheffield S3 7 H F (UK)
Dr. D. J. Williams, B. L. Allwood
Chemical Crystallography Laboratory
Department of Chemistry, Imperial College
London SW7 2AY (UK)
[**I This work was supported by the Science and Engineering, and Agricultural and Food, Research Councils in the United Kingdom, and by the
University of Messina in Italy. We thank Professor G. Stagno d’AIconfres, Messina, for granting leave of absence to F. H. K .
0 VCH Verlagsgesellrchajr mbH. 0-6940 Weinheim. 1985
0570-0833/8S/0707-0S81 $ 02.50/0
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octaphenyl, diazahexaphosphocine
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