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Heptacyclo[ 5.05 9.09 13.013 17.017 21]-tetracosane([6

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The findings presented here also demonstrate that, by
using viologen-dependent enzymes and by selecting viologens having different redox potentials, it is possible to
shift at will the equilibrium position of a reaction. An example is the equilibrium constant for reaction (a):
K=2.8 x 10"' for methylviologen (I?(,= -440 mV) at pH
6.0; K = 3 . 5 for CAV'O (Eb= -295 mV) at pH 8.5. Of
these ten orders of magnitude, five are due to the difference in pH (the hydrogen ion concentration is squared in
the expression for the mass action law) and five are due to
the difference in redox potential of methyl- and carbamoylmethylviologen.
This is not possible for pyridine-nucleotide-dependent
oxidoreductases, because the enzymatically active pyridine
nucleotide analogues so far known differ only slightly in
their redox potentials.
Received: September 23, 1986:
revised: November 18, 1986 [Z 1933 IE]
German version: Angew. Chem. 99 (1987) 139
[ I ] H. Simon, J. Bader, H. Gunther, S. Neumann, 1. Thanos, Angew. Chent.
97 (1985) 541; Angew. Chem. Int. Ed. Engl. 24 (1985) 539.
121 H. Gunther, S. Neumann, H. Simon, J. Biotechnol.. in press.
[3] S. Neumann, H. Gunther, H. Simon: European Congress on Biotechnology
i n i r d ) . Proceedings. Verlag Chemie, Weinheim 1984.
141 Tests carried out with the diammonium salt of 2,2'-Azino-di-3-ethy1-2,3dihydrobenzothiazole-6-sulfonicacid (ABTS) according to the method of
J. Putter, R. Becker in H. U. Bergmeyer, J. Bergmeyer, M. Grass1 (Eds.):
Methods of Enzymatic Analysis, Vol. 3. 3rd ed., Verlag Chemie, Weinheim
1983, p- 291.
[S] Macherey & Nagel Chiral-I column. The analyses were carried out by
elution with 3 mM copper sulfate solution.
161 W. Hurnmel, H. Schutte, M:R. Kula, Eur. J . Appl. Microbiol Biotechn. 21
(1985) 7.
17) H. Schutte, W. Hummel, M.-R. Kula, Eur. J. Appl. Microbiol. Biorechn. 19
(1984) 167.
[8] The viologen-dependent pyridine-nucleotide oxidoreductase was used for
regeneration: see H. Simon, H. Gunther, 1. Thanos in M. P. Schneider
(Ed.): Enzymes us Catulysfs in Orgunic Synthesis. D. Reidel, Dordrecht
1986, p. 35.
rangement of the expected homoallyl alcohol 5a (OH,,,,,,)
to 6, and cyclization with diisobutylaluminum hydride
(DIBAH)I4]to give 2 and/or 7 (see Scheme 1); second, hydrozirconization"' followed by bromination['l of 6 to give
10 and cyclization with tri-n-butyltin hydridei6] to give 2
(see Scheme 2). These approaches led not only to the synthesis of 2 and 3 but also to several surprising results.
Thus the addition of allylmagnesium bromide to 4l3]afforded not only the homoallyl alcohol 5a (m.p.= 145°C)
but also its conformational isomer 5b (m.p.= 154-156°C)
with an equatorial OH group. Both alcohols have such
high barriers to inversion [AG&3= 134.9 kJ/mol ( 5 a ) and
136.9 kJ/mol (5b)]I7Ithat they can be studied separately. In
order to induce the rearrangement, we took advantage of
the antiperiplanar arrangement of the hydroxyl group and
the axial bonds of the neighboring cyclobutane rings in Sa,
which favors the 1,2-shifts. Reaction with thionyl chloride
in pyridine afforded the expectedf3' hexacyclic diene 6
(m.p. = 189-196"C),'x''J whose cyclization with DIBAH was
then studied. Only at 160°C and upon addition of six molar equivalents of DIBAH did the reaction proceed beyond
simple addition of the hydride to the vinyl group and
hence formation of 8 (glassy solid),['] which had already
been observed at 80°C. However, GC/MS analyses provided no evidence for a cyclization with formation of 2
and/or 7. Instead, after 72 h at 160"C, the reaction mixture consisted of 49% 8 and 26% 9 (m.p.=24-27°C),[X"1
1tetracosane([6.5jcoronane)* *
By Detlef Wehle and Lutz Fitjer*
Polycyclic hydrocarbons in which a central m-membered
ring ( m = 4, 6, 8 ...) is coupled to rn peripheral n-membered
rings (n = 3 , 4 , 5 ...) such that each edge of the central ring
is simultaneously an edge of a peripheral ring ([m.n]coronaned'l) were previously unknown. They have an unusual
topology and should exhibit interesting chemical and physicochemical properties. Examples are the [6.4]coronane 1
and the [6.5]coronane 2, whose synthesis should be possiWe
ble via cascade rearrangements of penta~piranes.'~.~'
report here on the use of such a cascade for
the synthesis of the coronane 2 and of its incomplete
analogue 3.
We explored two possibilities for the synthesis of 2 :
first, addition of allylmagnesium bromide to 4:31 rear-
6 (92%)
5b(0He, 17%)
[*] Prof. Dr. L. Fitjer, DipL-Chem. D. Wehle
lnstitut fur Organische Chemie der Universitat
Tammannstrasse 2, D-3400 Gottingen (FRG)
Polyspiranes, Part 12: Cascade Rearrangements, Part 7. This work was
supported by the Deutsche Forschungsgemeinschaft (project Fi 191/6317-2) and the Fonds der Chemischen Industrie. D. W . thanks the
Fonds der Chemischen tndustrie fur a Chemiefonds fellowship.-Parts
11 and 6, respectively: L. Fitjer, M. Majewski, A. Kanschik, E. Egert,
G. M. Sheldrick, Tetrahedron Lett. 27 (1986) 3603.
0 VCH Verlagsge.~ellschuflmhH. 0-6940 Weinheirn. I987
8 (13%)
9 (49%)
3 (8777)
Scheme 1.
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Angew. Chern Int Ed. Engl. 26 (1987) No. 2
and after 1 1 d at 160"C, 13% 8 and 49% 9 were present.
The mechanism of the fragmentation remains to be explored.
Compound 9 was separated by gas chromatography and
hydrogenated over platinum dioxide in glacial acetic acid
to give 3 (glassy solid).lx"l We have studied this incomplete
[6.5]coronane in order to gain insight into the properties
expected for 2 . Its "C-NMR spectrum (50.3 MHz,
CHFCI,l"') exhibits only eleven signals at -78°C
[6=21.50, 21.81, 23.21, 30.23, 37.14, 38.29, 39.55, 45.42
(C,,,), 48.57 (C,,,,), 53.27, 55.98 (C,,,,,)], which are only in
accord with a rapidly inverting species in the all-cis configuration (effective symmetry: C,). At - 130°C, 21 signals
are observed [S=20.35, 20.84, 21.81, 22.20, 25.52, 28.94,
31.60, 35.46, 36.60, 37.37, 37.63, 39.26, 40.49, 45.45, 45.82,
47.58, 50.49, 52.21, 53.26, 55.51, 55.831 which must be ascribed to a fixed conformation having C,symmetry. Which
of the five conceivable conformations (one chair, two
twist-boat, and two boat conformations) is involved must
remain an open question, although force field calculationsl'('l support a flattened chair conformation
(C IWI,,,,,,~,~ ,,,,,=245"). In order to estimate the barrier to inversion, we followed the coalescence of the resonance lines
of the quaternary carbon atoms at 6=52.21 and 53.26.
From the frequency difference (Av= 52.7 Hz) and the coalescence temperature ( - I15_+5"C)
and using the Gutowsky-Holm relation and the Eyring equation, an extremely
low value of AG = 3 1.3 +- 1.1 kJ/mol for the free energy
of activation resulted. It thus appeared certain that the
[6.5]coronane 2 would be characterized by a similar low
barrier to inversion.
We then investigated the synthesis of 2 via the second
approach outlined above (Scheme 2). For this purpose the
diene 6 was first hydrozirconized with zirconocene chloride hydrideI5' and then brominated with N-bromosuccin-
imide (NBS).I5] Chromatography on silica gel with hexane
afforded pure 10 (m.p.=35-37°C).1H"1In order to carry out
the cyclization, a solution of 10 in benzene was heated
with 2.0 equivalents of tri-n-butyltin hydride and 0.2 equivalents of azobisisobutyronitrile for 38 h at 80°C. Complete consumption of 10 led to the formation of at least
eight products, including, as main product, the heptacyclic
13 (m.p. = 164°C)[";'1 and, as side products, the already
known 8 and the sought [6.5]coronane 2 (m.p.=222224"C).1x"1Separation was achieved by a combination of
column and gas chromatography.'xh1
The structural assignment of 13 is based on the available spectroscopic data,['"] especially on the number, position, and multiplicity of the signals in the "C-NMR spectrum. The configuration results from the fact that the radical 11 can only attack the double bond from the side
shown and the resulting 12 should be configuratively stable. It is not surprising that 13 is preferentially formed although it is the product of an unfavorable endo-trig ring
closure according to Baldwin's rules.11'.
The structure and configuration of the title compound 2
could be assigned unequivocally. The I3C-NMR spectrum
(50.3 MHz, CD,CI,) shows only three signals at 20°C at
6=21.24,40.07 (C,,,), and 56.80 (C,,,,,), which are only in
accord with a rapidly inverting species in the all-cis configuration (effective symmetry: &J. On account of the extremely low solubility of 2,[I3I we had to always use
[D2]dichloromethane for the low-temperature "C-NMR
investigations. At - 80°C, the signal at 6=40.07 clearly began to broaden, until, at -94"C, the lowest temperature
attainable in [D,]dichloromethane, it exhibited a halfwidth
(12 Hz) five times that of the still sharp signals at 6 ~ 2 1 . 2 4
and 56.80. We are therefore certain that this signal will be
split at lower temperature into two resonances, as expected
for a fixed chair conformation. Even the most careful estimate of the coalescence temperature ( - 100°C) and the
frequency difference (20 Hz) gives the expected low value,
AG = 36 kJ/mol, for the corresponding barrier to inversion.
Most interesting is the finding that the barriers to inversion of 5a and 5b are extremely high, whereas those of 2
and 3 are extremely low. This clearly indicates that on going from spiroannelation, as in 5a,b, to edge-annelation,
as in 2 and 3, the central ring is flattened in the ground
statel"l and the 1,2-interactions are reduced in the transition state. Both effects should be even more pronounced in
the [6.4]coronane 1.[I4] Therefore, we expect the barrier to
inversion for 1 to be even smaller than that for 2.
13 (32%)
Received: September 29, 1986;
revised: November 17, 1986 [Z 1941/1942]
German version: Angew Chem. 99 (1987) 135
+ BujSnH
- BujSnBr
- BUjSnO
1. C q Z r C l H
I *. NBS
8 (7%)
+ Eu3SnH
- Bu3sno
Scheme 2.
Angeu. Chem. Int. Ed. Engl. 26 (1987) No. 2
2 (8%)
[ I ] L. Fitjer, D. Wehle, Angew. Chem. 91 (1979) 927; Angew. Chem. In/. Ed.
Engl. 18 (1979) 868. Recently, it was suggested [J. A. Marshall, J. C.
Peterson, L. Lebioda. J . Am. Chem. Soc. I06 (1984) 60061, t h a t [m.n]coronanes should be regarded as members of a more inclusive family, the
perannulanes. Accordingly, the [6.5]coronane would be called all-cis[]hexannulane.
[Zl L. Fitjer, D. Wehle, M. Noltemeyer, E. Egert, G. M. Sheldrick, Chem.
Ber. I 1 7 (1984) 203.
[3] L. Fitjer, M. Giersig, W. Clegg, N. Schormann, G. M . Sheldrick, Tetrahedron Lett. 24 (1983) 5351.
[4] The use of DIBAH to effect spiroalkylation to give a derivative of the
spiro[4.4]nonane is known: P. W. Chum, S . E. Wilson, Tetrahedron Left.
17 (1976) 1257. Our own studies with 1-(3-butenyl)cyclopentene, using
DIBAH in excess, led to high yields of spiro[4.4]nonane itself: L. Fitjer,
D. Wehle, unpublished results.
[S] J. Schwarz, J. A. Labinger, Angew. Chem. 88 (1976) 402: Angew. Chem.
Int. Ed. Engl. 15 (1976) 333.
0 VCH Verlagsgesellschaji mbH. 0-6940 Weinheim. 1987
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f 31
[6] A. L. J. Beckwith, K. U. lngold in P. d e Mayo (Ed.): Rearrangements in
Ground and Excited Stater. Vol. I. Academic Press, New York 1980,
p. 161.
[7] D. Wehle, L. Fitjer, Tetrahedron Leu. 27 (1986) 5843.
181 a) All new compounds ( 2 , 3, 6, 8 , 9, 10, and 13) gave correct elemental
analyses and/or high-resolution mass spectra. The 1R, 'H-NMR, and
mass spectra are in accord with the given structures. "C-NMR data: 2
(CDCI.3): 6=21.16, 40.30 (C,,,),
57.33 (C,,,,,,); 3 (CDCI,, -39°C):
6=21.70, 21.83, 23.27, 30.17, 37.58, 38.49, 39.80, 45.11 (C,,,),
6 (C,D,): 6=21.38 (two signals overlap),
53.52, 56.05 (C,,,,,,);
21.69, 24.07, 29.44, 36.71, 37.14, 38.25, 39.37, 39.45, 39.61, 40.09, 40.21,
125.10, 137.17 (C,,,,),
150.66 (Cqv.,r,);8 (CDCI,): 6= 14.80 (C,,,,),
18.90, 21.20, 21.26, 21.44, 23.64, 29-17, 36.39, 36.62, 38.07, 39.03, 39.25,
49.25, 56.88, 58.17, 58.42, 58.89
39.48, 39.69, 39.71, 39.99, 40.38 (C,,,),
( C ,",,, c ) , 124.16(C,,,,), I50.38(Cq,,,,);9 (CDCI~):6=21.00,21.21,21.67,
23.28, 26.05, 29.99, 34.1 1, 37.64, 37.73 (two signals overlap), 38.18, 38.42,
39.28,40.02 (C,,,),
41.73 (C,,,,), 56.86, 56.98, 58.84, 6O.04(Cq,,,,), 119.80
150.60 (C,,.,,,); 10 (CDCI,): 6=21.14 (two signals overlap),
21.44, 23.58, 29.20, 29.57, 34.94, 36.27, 36.40, 36.86, 38.16, 39.01, 39.34,
39.56 (two signals overlap), 39.63, 40.38 (C,,),
48.76, 56.97, 58.18, 58.61,
58.98 (Cqu,trL),124.96 (C,,,,), 149.88 (C,,,,,); 13 (CDCI,): 6=21.36,
21.51, 21.57, 22.04, 23.89, 28.68, 30.38, 31.47, 32.95, 34.88, 36.33, 37.11,
46.43 (C,,,,,), 47.12 (C,,,,),
37.15, 38.54, 38.94, 39.00, 39.28, 40.72 (C,,),
53.86, 57.69, 59.36, 59.52 (C,,,,,). b) Preparative glc o n column A
[0.6mx 1/4" all-glass system, 12% FFAP on chromosorb W AW/
DMCS, 60/80 mesh, 210"C, 200 mL HJmin: relative retention times:
0.76,0.87, 1.00 (8), 1.1 I , 1.75, 2.00, 2.45 12/13), 3.531 yielded pure 8 and
an impure mixture of 2 and 13. This mixture was purified on silica gel
(0.1-0.2 mm) with hexane [R,=0.61 (2/13)] and then separated on column B [1.6mx 1/4" all-glass system, 2% G E SE30 on chromosorb W
AW/DMCS, 60/80 mesh, 200"C, 130 m L Hz/min; relative retention
times: 1.00 ( 2 ) and 1.10 (13)l.
[9] GC(CHFCl2)= 100.95 and 106.82; these values were measured for a saturated solution of dichlorofluoromethane in CDCIJTMS (95 : 5 v/v).
[lo] Program MM2: N. L. Allinger, J. Am. Chem. SOC.98 (1977) 8127; D.
Wehle, L. Fitjer, unpublished results.
[ I I ] J. E. Baldwin, J . Chem. SOC.Chem. Commun. 1976. 734.
[I21 An endo-trig ring closure was also observed for 7-bromo-3-methyl-trans2-heptene, which is similar to 10 in terms of substitution pattern and
stereochemistry: M. Julia, C. Decoins, M. Baillarge, B. Jaquet, D.
Uguer, F. A. Groeger, Tetrahedron 31 (1975) 1737.
[I31 1.5 mg of 2 in 500 pL of dichlorofluoromethane (m.p.= - 135°C) could
be maintained in solution only down to 0°C; at -4O"C, most of the
substance had precipitated.
[I41 According to force field calculations ( M M 2) 2 has a significantly flattened chair conformation [Z lmlcent,',,,,,,=237O] [lo, 151. This effect is
still more pronounced for 1 [ZIml,,,,,.,l
136'1 [15].
1151 H. Dodziuk, Bull. Chem. SOC.Jpn., in press; we thank Dr. Dodziuk for a
preliminary copy of her article.
the formation of these unusual complexes involves an initial oxidative addition of the element hydride to the reactive complex fragment LxM according to Equation (a), followed by coupling with elimination of H2.L1.4J
This suggestion, which so far has remained more or less speculative, is
now supported by the first successful oxidative addition of
hydrogen telluride to a transition metal.
- ,
Treatment of the substitution-labile solvent complex 2,
generated by photolysis, with externally generated, acidfree hydrogen telluride in tetrahydrofuran at room temperature in the dark (!) affords, after column-chromatographic
workup of the crude product at low temperature, the four
new organorhenium complexes 1 and 3-5 (Scheme 1).
The components of the hydride TeH2 are completely maintained only in the mononuclear complex 1. According to
'H- and I2'Te-NMR spectroscopy and an X-ray diffraction
study, 1 is a TeH/H complex of type A with nearly
square-pyramidal coordination around the transition-metal atom and a trans arrangement of the ligands TeH and
H (Fig. l a , Table 1).
lh Y . 30 min
Scheme I
Oxidative Addition of Hydrogen Telluride to
Organometallic Fragments**
By WoIfgang A . Herrmann,* Christian Hecht,
Eberhardt Herdtweck, and Heinz-Josef Kneuper
A large number of reports have appeared recently concerning the advantages of using simple binary hydrides,
such as GeH,, SnH4, AsH3, and TeHZ, to incorporate unsubstituted main-group elements into organometallic complexes.['' Examples of compounds thus formed under mild
conditions and usually in good yields, are the tin and
tellurium compounds LxM=Sn=MLx (linear) and
(LxM =($C5R5)Mn(CO),; R = H, CH3).f2.3e1
The star-shaped complex [(p3-Te)((qS-CsH5)Mn(C0)2}3]
was also obtained in
this way.[3b1The working hypothesis that is used to explain
Prof. Dr. W. A. Herrmann, Dr. C. Hecht, Dr. E. Herdtweck,
Dr. H.-J. Kneuper
Anorganisch-chemisches lnstitut der Technischen Universitat Miinchen
Lichtenbergstrasse 4, D-8046 Garching (FRG)
[**I Multiple Bonds between Main-Group Elements and Transition Metals,
Part 33. This work was supported by the Fonds der Chemischen Industrie, Hoechst AG, and the Bundesministerium fur Forschung und Technologie.-Part 32. [71.
0 YCH Verlagsgesellschaj2 mbH, 0-6940 Weinheim, 1987
Isolated 1, a dark red-brown solid, is thermally stable
under inert atmosphere but remarkably photolabile. Irradiation with UV light, filtered through Duran glass, results
in the nearly quantitative transformation of 1 to 3 with
elimination of HZ; 3 is the most stable of the four complexes. This complex contains a n unsymmetrical Te,
bridge (Fig. lb, Table l), which until now had only been
observed in organometallic compounds containing sulfur
or ~elenium.[~.'l
The bond lengths in the RezTez skeleton
are in accord with the number of electrons in this fragment. Thus, the Re2-Te2/1 distances [279.3( < 1)/
280.6( < 1) pm] are consistent with a n-type side-on complexation of a Te, fragment,[" and the Rel-Tel distance
[263.2( < 1) pm] is not inconsistent with the postulated
ReTe double bond. By way of contrast, ReTe single bonds
are estimated to have lengths of ca. 285 ~ m . [ ~ ]
Complex 3 can also be obtained from the isomeric complex 5 either photochemically (irradiation with UV light in
THF) or thermally (refluxing THF). This unusual isomerization reaction is restricted to the constitution of the
The red-brown complex 4, which contains a RezTe
three-membered ring and is formed in only small amounts,
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013, 017, tetracosane, heptacyclo
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