close

Вход

Забыли?

вход по аккаунту

?

New Cryptates Containing Tricyclic Ligands Crystal Structure of C32H64N4O10╖2NaI.

код для вставкиСкачать
carbon demands comment. We have previously noted that
increasing strain causes an upfield I3C chemical shift. Examination of spectra of several tricyclo compounds such
as ( 5 a ) , ( 3 a ) , ( 6 a ) and tricycl0[2.2.0.0~~~]hexane (8)
shows that the highest signals appear in the range 6 15-20
ppm, i.e. ca. 3-0
ppm lower than that due to C-7
of ( 4 a). This definitely suggests that the s,p-hybridization
of the carbon bonding orbitals is unique and further that
only a minimal positive charge resides at this carbon.
Although the choice between the single cation ( 4 0 ) or
an equilibrating pair of ( 4 b ) and ( 4 c ) remains to be
made, other theoretical and experimental results presently
accumulating tend to place a slight preference for (4a)
rather than (4b) and (4c) as the particular species obtained
in superacid mediafi3].
Received: July 2, 1973 [Z 880 IE]
German version: Angew. Chem. 85,829 (1973)
[ I ] S. Masamune, M . Sakai, and H. Ona, J. Amer. Chem. SOC.94, 8955
(1972). S. Masamune, M . Sakai, H . Ona, and A . J . Jones, J. Amer. Chem.
SOC.94, 8956 (1972). For theoretical arguments on the cation ( I ) , see:
W D. Stohrer and R. Hofmann, ibid. 94, 1661 (1972); S. Yoneda and
Z . Yoshida, Chem. Lett. 607 (1972); W J . Hehre, private communication.
[2] S. Masamune, R. Vukoi,, M. J . Bennett, and J . 7: Purdhum, J . Amer.
Chem. SOC.94,8239 (1972). Related works were more recently reported:
P. C. Cassman and X . Creary, J. Amer. Chem. Sac. 95, 2129 (1973).
[3] S. Masamune, S. Takada, N . Nakatsuka, R. Vukov, and E . N . Coin,
J. Amer. Chem. SOC. 91, 4322 (1969); S . Mnsamune, E. N . Cain, R.
Vukov, S. Takada, and N . Nakatsuka, Chem. Commun. 1969, 243.
[4] For a similar sequence of reactions, see: H. H. Westberg, E. N .
Cam, and S. Musamune, J. Amer. Chem. SOC.91, 7512 (1969).
[5] The C-4 proton of (5a) and (5b) appears at T 5.66 and 4.62 (CDCI,),
respectively. The intensity of these signals were compared with those
in the aromatic region. ( 5 a ) was converted to ( 5 6 ) for this analytical
purpose
[6] J . B. Stothers, C . T. Tan, A. Nickon, F . Huang, R. Sridhar, and
R. Weglein, J. Amer. Chem. SOC. 94, 8581 (1972): D. H. Hunter, A.
I-. Johnson, J . B. Stothers, A. Nkkon, J . L. Lambert, and D. F. Corey,
J . Amer. Chem. SOC. 94, 8583 (1972). The assignment t o C-2 and C-7
may be reversed.
171 R. K . Lustgarten, J. Amer. Chem. SOC.94, 7602 (1972).
[8] For a recent review on long-lived carbocations, see: G. A. Olah,
Angew. Chem. internat. Edit. 12, 173 (1973).
[9] Attempts to generate (4n) from the hydroxy and methoxy derivatives
corresponding to ( 3 r ) and ( 5 d ) apparently led to the protonation of
the cyclopropane ring as well as the hydroxy group and resulted in
entirely different cations.
[lo] The numbering of ( 4 a ) is arbitrary.
[ I l l J . D. Roberts, W.Bennet, and R. Armstrong, J. Amer. Chem. SOC.
72, 3329 (1950): S . Winstein, H. M. Wafborsky, and K . Schreiber, J.
Amer. Chem. SOC.72, 5795 ( I 950).
[I21 H . Hart and M . Kuzuya, J. Amer. Chem. SOC. 94, 8958 (1972).
[I 31 Solvolytic (trifluoromethanesulfonate) and deamination studies of
( 9 ) showed no indication of double bond participation. Cf. W Kirmse
and F. Scherdt, Angew. Chem. internat. Edit. 10, 263 (1971).
New Cryptates Containing Tricyclic Ligands:
Crystal Structure of C ~ Z H ~ ~ . N
2NaI
~OI~
By Michel MeIIinger, Jean Fischer, and Raymond Weissc*l
In solution the macrocycle ( I ) forms inclusion complexes
of the [3]-cryptate type, e. g. with sodium iodide it forms
the 1 :2 complex ( I ) .2NaI[''.
This compound crystallizes in space group P2,/c with
a=8.726(4), b= 10.114(7), ~=24.422(11)A, p = 103.89(4)",
d e x p =1.52+0.05, d,,l,=1.530 g/cm3 and Z = 2 .
[*] Prof. R. Weiss, M. Mellinger, and Dr. J. Fischer
Institut de Chimie, Laboratoire de Cristallographie associt au
C.N.R.S.
Universitt Louis Pasteur
F-67008 Strasbourg, B. P. 296/R8 (France)
Angew. Chem. internat. Edit. 1 Vol. 12 (1'973) / N o . 9
The intensities of the X-ray reflections were measured
for a spherical crystal of diameter 0.3mm with Mo-K,radiation on a Picker-FACS(1) single crystal diffractometer.
2304 independent reflections with o(l)/l<30 were used
for the structure analysis. At present the R value amounts
to 0.069.
Figure 1 shows the structure of the complex dication of
( 1 ) .2NaI, which has a crystallographic center of symmetry. Two sodium ions are accommodated inside the tricyclic
ligand, each of them being bonded to two nitrogen and
five oxygen atoms of (I).
Fig. I . Crystal structure ofthecomplex dication of the inclusion compound
(1) . 2 NaI.
The distances from Na' to N1 and N2 are 2.70(1) and
2.71(1) 8, respectively, and t o 0 1 , 0 2 , 0 3 , 0 4 and 0 5 ,
vary between 2.39(1) and 2.48(1) A. Similar values were
found for the [2]-cryptate (222). NaI and for the complex
sodium salts with cyclic polyethers[', '1.
The iodide ions no longer interact with tbe sodium ions:
all the N a + - I - separations exceed 5 A. The distance
between the two sodium ions in one ligand is 6.40A.
The determination of this structure confirms the finding
that the tricyclic ligand ( 1 ) can enclose two metal cations.
The two holes in this molecule have approximately the
samediameter as in the bicyclic ligand (222) of the [2]-cryp
tate (222).NaI, which has proved very stableI2].
The stability of the [3]-cryptate and the selectivity of
the tricyclic ligand are less marked than for the [2]-cryptate
and the bicyclic ligand, re~pectively[~].
This is probably
due mainly to greater flexibility of the tricycle.
Received: June 22, 1973 [Z X78 IE]
German version. Angew. Chem 85. 828 (1973)
[l] J . M . Lehn, J . Simon, and J . Wugner, Angew. Chern. 85,622 (1973).
Angew. Chem. internat. Edit. 12. 579 (1973).
[2] D. Moms and R. Weiss, Acta Crystallogr. 8 2 9 , 396 (1973).
[3] M . 4.
Biish
and M R. Entw. J. C. S. Pcrkin 11 1972. 341.
[4] J . Chenej. J . M. Lehn, J . P . Saucage. and M . E . Stuhhs, J. C. S. Chem.
Comm. 1972,1100.
771
Документ
Категория
Без категории
Просмотров
0
Размер файла
129 Кб
Теги
crystals, cryptates, structure, containing, c32h64n4o10, tricyclic, 2nai, new, ligand
1/--страниц
Пожаловаться на содержимое документа