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Intermolecular Exchange of Substituents via lons (Ion Pairs) in Cyclopentadienyl- and Cyclononatetraenyl-trimethylstannane.

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described above. Dibutyl disulfide is isolated by vacuum distillation (b.p. 94-97 "C/7 torr, yield 2:5 g = 56 % based on sulfur).
Received: November 23, 1978 [Z 151 IE]
German version: Angew. Chem. 91, 228 (1979)
CAS Registry numbers:
( 1 a ) , 1823-91-2; ( 1 b ) , 5558-87-2; (1 c), 5558-29-2; (1 d ) , 86-29-3; (1 e).
.
( 2 b ) , 69309-43-9; ( 2 c ) , 69309-44-0; ( 2 d ) ,
140-29-4; ( 2 ~ ) 67073-81-8;
67073-82-9; ( Z e ) , 53310-49-9; ( 3 ) , 2450-55-7; ( 4 a ) (n= I ) , 544-40-1 ;
( 4 ~ () n = 2 ) , 629-45-8; ( 4 ~ )(n=3), 5943-31-7; (46) (n=2), 4253-89-8;
( 4 c ) (n=2), 822-27-5; CH3Br, 74-83-9; n-C4H&I, 109-69-3; ethylene dibromide, 106-93-4; CC,H,CI, 75-29-6; n-C8H,,CI, l l 1-85-3; Ph2C(CN)C(CN)Phl, 3122-21-2
[ l ] Reactions of Organic Anions, Part 93. This work was supported by
the Polish Academy of Sciences. -Part 93: A. Joriczyk, A . Kwast, M .
MGkosza, Tetrahedron Lett., 1979, 541.
[2] K . A. Kocheshkoa, 7: !/ Talalarcu- Mietodi elementoorganicheskoi khimii
(litij, natrij, kalcij, ruhidij, cezij), Vol. 2. lzdatelstvo Nauka, Moskva
1971, p. 594; L. Brandsma: Preparative Acetylenic Chemistry, Elsevier,
Amsterdam 1971, p. 83; K . Nutzel in Houben-Weyl-Muller: Methoden
der Organischen Chemie. 4th Ed. Vol. XIII/2a, Thieme, Stuttgart 1973,
p. 399.
131 D . N . Brattesoni, C . H . Heathcock, Tetrahedron Lett. 1974, 2279; P.
A . Gassman, D. P . Gilbert, S. M. Cole, J . Org. Chem. 42, 3233 (1977);
P . A . Gassman, R . J . Balchunis, ibid. 42, 3236 (1977), and literature
cited therein. Also see ref. [ S ] .
[41 For reviews see, e , g . : M . Mpkosza, Pure Appl. Chem. 43, 439 (1975);
E. !/ Dehmlow, Angew. Chem. 86, 187 (1974); 89, 521 (1977); Angew.
Chem. Int. Ed. Engl. 13, 170 (1974); 16, 493 (1977).
[51 For synthesis of ( 2 ) , see a ) S. J . Selikson, D : S . Watt, Tetrahedron
Lett. 1974. 3029; h) M . M&osza, M . Fedoryriski, Synthesis 1974, 274;
c) E . Marchand, G . Morel, A . Foucaud, ibid. 1978, 360.
symmetry controlled process or as one obeying the principle
of least motion"] [(Z')+(l)]. We have found that, given
suitable solvation, 1,3-cyclopentadienyl- and 1,3,5,7-cyclononatetraenyl-trimethylstannane (I ) and (3 ), respectively,
can exist as ions (ion pairs) and exhibit intermolecular substituent exchange (Do=donor solvent or LiCI).
Fast intramolecular exchange in the case of (1) in tetrahydrofuran (THF) (see Fig. 1 a), dimethoxyethane (DME), trichloro-, dichloro-, or dichlorodifluoro-methane between 26
(Fig. 1 a) and - 70°C is characterized, inter a h , by the sharp
satellite bands of the signal of the five cyclopentadienyl
protons at 6 = 5.92, which are due to 1 1 7 , 1 1 'Sn-C-lH
coupling ( J =22 Hz)[''.
If the T H F solution of ( 1 ) is treated at 26°C with hexamethylphosphoric triamide (HMPT) (0.85mol. equiv.), a broadening
of the satellite signals is observed (Fig. 1 b). Lowering the
temperature of this sample leads to further broadening
(- 48 "C, Fig. 1 c) and coalescence (- 61 "C, Fig. 1 d). A similar
sequence of events occurs at constant temperature on increasing the concentration of HMPT, dimethylformamide (DMF),
or lithium chloride. A spectrum like that in Figure I d is
obtained, e.g. with 0.54mol. equiv. of LiCl in T H F at 26°C.
It is fully compatible with known ion-pair
and
is adequately confirmed by the results obtained for cyclononatetraenyltrimethylstannane (3), that the disappearance of the
satellite signals with increasing concentration of donor solventc3]or LiCI, and with falling temperature, should be due
to an increasing shift of the equilibrium ( 1 ) $ ( 2 ) in favor
ofthe ion pair (2) (low concentrations) and thus to an mtermolecular substituent exchange.
Intermolecular Exchange of Substituents via Ions (Ion
Pairs) in Cyclopentadienyl- and Cyclononatetraenyl-trimethylstannane
By Gernot Boche, Frank Heidenhain, and Brigitte Staudigl[*l
The behavior of q I-cyclopentadienyl derivatives of main
groups IV and V, which is dynamic on the NMR time scale,
has generally been recognized as an intramolecular orbital-
H SnMe3
6
OFnMe3
+ Do
@ ?Me3
Do
(13
Q
(1)
b
(21
C
d
(31
(37
While (3) likewise exists as an olefinic ql-compound with
fast intramolecular substituent migration (3')*(3)['1 in solvents of low donor strengthC3],the solvents DMF, HMPT,
and dimethyl sulfoxide (DMSO) lead to a distinct shift of
the ring protons from the olefinic region to that of the [9]annulene anionI6] (see Table 1). This is because the equilibrium
(3)*(4) lies more on the side of the ion pair than in the
case of ( I )+(2) because of the easier ionization of the ninemembered ring derivative (3)[']. Accordingly, valence isomerization to dihydroindenes, such as are common for cyclononatetraenes [e.g. (3)151],no longer occurs. The coupling constants
.J("731
19Sn-C-1H)also increase in parallel with the shift in
equilibrium (3)$(4). This is due to the stronger complexing
ability of the above-mentioned donor molecules towards
( 4 ) I 1 c, 81,
In a mixture of DME :D M F = 2 : 1, roughly the same population of (3) and ( 4 ) is attained, permitting determination
of the temperature dependence of the equilibrium. The finding
Table 1 . 'H-NMR data of ( 3 ) in solvents of various donor strengths; 6
values relative to TMS at 37°C.
I
I
592
592
Solvent
L
592
592
strength
Fig. 1. 'H-NMR spectra (6 values) of cyclopentadienyl-trimethylstannane
( J ) under various conditions (a-d, see Text).
[*] Prof. Dr. G. Boche, Dip].-Chem. F. Heidenhain, DipLChem. B. Staudigl
lnstitut fur Organische Chemie der Universitat
Karlstrasse 23, D-8000 Munchen 2 (Germany)
218
Donor
CDCI,
THF
DME
DMF
DMSO
HMPT
~-
131
-
20
x 24
26.6
29.8
38.8
' ' ', ' '9Sn.C-
Ring-H
J(
( 6 value)
[Hzl
5.33
5.35
5.33
6.42
6.72
6.70
51
51
5s
62
1
H)
65
71
Angew. Chrm. Int. Ed. Engl. 18 (1979) N o . 3
8 Verlag Chemie, GmbH, 0-6940 Weinheim, 1979
0570-0833/79/0303-0218
$02.50/0
that ( 3 ) is present at room temperature and that ( 4 ) predominates at -40°C corresponds to a reaction enthalpy of AHo=
-8.8 [kcalmol-’1 and an entropy of reaction ASo= -32
[e. u.] for the transformation ( 3 ) + ( 4 ) , with the entropy
term in particular confirming the solvation of the ion pair.
Since only averaged spectra were recorded throughout the
entire temperature range, the equilibrium ( 3 ) =$ ( 4 ) must be
mobile (AGf400CI 10 [kcalmol-’I). Addition of 1 mol. equiv.
of LiCl to a 0 . 4 ~
solution of ( 3 ) in THF leads to similar
behavior: as the temperature falls the dynamic equilibrium
( 3 ) + ( 4 ) shifts reversibly to the side of the ion pair ( 4 ) .
( I ) and ( 3 ) thus demonstrate that covalent trimethylstannyl
compounds can be transformed by suitable solvents into ion
pairs (2) and ( 4 ) which react differently from ( I ) and (3)[91.
Received: December 4, 1978 [Z 152 IE]
German version: Angew. Chem. 91, 228 (1979)
15J
Such multi-loop crown ethers should not only be useful
for the analysis of mixtures of salts[‘] but also attract interest
for the enzyme-analogous complexation of polyfunctional
organic compounds and polyelectr01ytes~~I
and as models for
cation contact, charge transfer, and energy transport proc e ~ s e s [ ~The
] . ligands having topologies ( 1 ) - ( 5 ) , e. g. (6)
and ( 7 ) were synthesized using pentaerythrit~l[~]
as starting substance (Tos = toluenesulfonyl, THP = tetrahydropyranyl).
CAS Registry numbers:
( I ), 2726-34-3; ( 3 ) . 69429-52-3
[I]
[2]
[3]
[4]
[5]
161
171
[8]
[9]
a) H . P. Fritz, C . G. Kreiter, J . Organomet. Chem. 4, 313 (1965); reviews:
b) F . A . Cotton in F . A . Cotton, L. M Jackman: Dynamic Nuclear
Resonance Spectroscopy. Academic Press, New York 1975, p. 377; c)
V S. Petrosyan, Prog. NMR Spectrosc. 11, 115 (1977).
a) Line broadening is observed below -70°C and at =-105”C the
satellites under the signal at 6=5.92 disappear [2b-d]. At -150°C
splitting to an AABB’X spectrum occurs with signals at b=6.5 and
at R=4.25 [Zh]; b) A . V Kisin, f! A. Koreneusky, N . M . Sergeyeu,
Y. A. Ustynyuk, J . Organomet. Chem. 3 4 , 93 (1972); c) A. Dauison,
P. E. Rakita, J . Am. Chem. SOC.90, 4497 (1968); d) R. B. Larrahee,
J . Organomet. Chem. 74, 313 (1974).
V Gurmann: Coordination Chemistry in Non-Aqueous Solutions. Springer, Wien 1968.
a) M. Szwurc: Ions and Ion Pairs in Organic Reactions. Wiley, New
York, Vol. I, 1972, Vol. 11, 1974; b) G. Boche, F . Heidenhain, Angew.
Chem. 90. 290 (1978); Angew. Chem. Int. Ed. Engl. 17, 283 (1978);
c) J. Am. Chem. SOC.101, in press.
G. Boche, f.Heidenhain, J . Organomet. Chem. 121, C49 (1976).
7: J . Kutz, P. J . Garratt, J . Am. Chem. SOC.85, 2852 (1963); 86, 5194
(1964): E. A. Lalancette, R. E. Benson, ibid. 85, 2853 (1963); 87, 1941
(1 965).
pK, measurements on cyclopentadiene and cyclononatetraene show the
same tendency [6].
a) V S. Petrosyun, N . S . Yushina, V 1. Bakhmutov, A. B. Permin, 0.
A. Reutor, J. Organomet. Chem. 72, 71 (1974); b) V. S. Perrosyan, 0.
A. Rrutoo, Pure Appl. Chem. 37, 147 (1974).
See also a) I. P. Beletskaya, A. N . Kashin, 0. A. Reutoa, J. Organomet.
Chem. 1 5 5 , 31 (1978); b) I. P. Beletskuya, A. N . Kaslrin, A. Z . Malhusyan,
A. A. Solouyanou, E . U . Behly, 0. A. Reutoi;, Zh. Org. Khim. 10, 678
(1974): c ) I. P . Beletskuya, A. N . Kushin, V. A. Khutoryanskii, 0. A.
Reutoc, Izv. Akad. Nauk SSSR, Ser. Khim. 1976, 1674.
“Multi-Loop Crown Ethers” with Multiple
Selectivity[**]
By Edwin Weber[*l
While the chemistry of organic neutral ligands has made
great advances with regard to the specific recognition of individual types of cations/anions and uncharged molecules[’],
apparently, very little is known about receptors (host
molecules) for the simultaneous selective complexation of
several d(ffrent types of alkali metal/alkaline earth metal and
heavy metal ions. We report here on the first crown ether
combinations “multi-loop crown ethers” of type (1 )-(5),
in which several rings having tailor-made cavity sizes and
donor properties are coupled via spiro C-atoms.
[*I Dr. E. Weber
Institut fur Organische Chemie und Biochemie der Universitat
Gerhard-Domagk-Str. 1, D-5300 Bonn (Germany)
[**I Thanks are due to Prof. Dr. F . Viigtlr for valuable discussions and
to Ms E . Wuhrburg for experimental assistance.
NaH’THF
k
i
I
i
1
k=t = 2
16~):k
(6dl:
(6el:
:1
i
3
k = 3. I =1
k = 5.
1=1
J“
1.
(?a]:
k
i
3. rn i 2. n i3
17bl: k = 2,
(7cJ: k 1.
17dl: k = 2.
rn = 2.
n=L
m = 3.
n=1
rn
3. n = 2
The ligands (6a)-(6e) and (7a)-(7d) have been shown
to be generally useful as hosts for the joint incorporation
of several cations, and the ratio ionic radius/cavity volume
of crown ether (donor number) for each ring can be adjusted
at will.
The double-loop crown ether (6 b ) (colorless viscous oil)[61,
for example, readily forms a 1 :2complex with NaSCN or
with Ca(SCN)2, i. e. each of the two similar “crown-5,5” rings[71
incorporate a metal ion-as
in ( I ) (Table 1). The same
applies for the bulkier “dicrown-6,6” ligand (6 c ) (colorless
Table 1. Complexes of the multi-loop crown ethers ( 6 ) and (7).
No.
Ligand
Type
Stoicliiometry
Ligand. Salt
Complex
Salt
(6a)
(6b)
“4,4”
“5,s”
1:2(2H20)
1:2
1:2
I:1
3:4
LII
NaSCN
Ca(SCN),
KSCN
Bd(SCN)2
(6c)
“6.6”
(6d)
“4,6”
1 : 2 (1 H 2 0 )
1 : 2 (1 H 2 0 )
1:2 (4H20)
1:l:l
1.2
1:l (2H20)
Barz
Ba(SCN),
LiI
LiI, Ball
LiI
Bar,
(7u)
“6,6,6”
I :3
KSCN
M. p. [“C]
> 300, dec.
204-206
> 300, dec.
193- 195
234 (sinters at
229°C)
> 350, dec.
275-276
12-74
280, dec.
196- 198
225 (sinters at
95°C)
273-~-275
219
A I I ~ I MChrin.
..
Inr. Ed. Engl. 18 ( 1 9 7 9 ) N o . 3
0 Verlug Chemie, GmbH, 0-6940 Weinheim, 1979
(6al:
(661:
I
0570-0833~79j0303-02I9 $02.5010
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lons, exchanger, intermolecular, ion, substituents, pairs, cyclopentadienyl, trimethylstannyl, via, cyclononatetraenyl
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