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Ring-Expanding Metathesis of Tetradehydro-anthraceneЧSynthesis and Structure of a Tubelike Fully Conjugated Hydrocarbon.

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Ring-Expanding Metathesis of Tetradehydroanthracene-Synthesis and Structure of a
Tubelike, Fully Conjugated Hydrocarbon**
Stefan Kammermeier, Peter G. Jones, and
Rainer Herges*
140 120
C I A 100
In principle, tubelike molecules[’] can be synthesized in three
ways (Scheme 1 ) . Firstly, rings can be stacked, as was successful
with cyclodextrins,[’I cy~lopeptides,[~]
and cyclic hydrocarbons,C41 and which is probably how “nanotubes” are formed in
40 -
mFig. 5 . A plot of the refined c-axis lattice parameters for the superlattices versus the
desired number ofTiSe, units m,the unit cell ofthe superlattice. The linear relationship between these parameters highlights the ability of this approach to design the
structure of the desired final product through control of the initial reactant.
develops along the c axis as the superlattice structures are kinetically trapped.
This synthetic advance sets the stage for the synthesis of materials with unexpected bonding and mechanical and electrical
properties that can be systematically examined as a function of
heterostructure length scales. Other phenomena, such as phase
transformations and interface-related processes in thin-film and
layered alloys. may also be profoundly different in these heterostructured materials from those which are now well-known
in the bulk alloy or composite systems. In addition, a transition
from composite behavior to that of a new compound should
occur as the length scale of the compositional modulation decreases; the length scale of the transition would depend upon the
property being monitored. This new synthesis approach provides new opportunities to probe for these effects by enabling
the preparation of superlattice materials for which epitaxial
growth conditions have yet to be determined. This ability to
synthesize new “designed” layer structures from superlattice
reactants also implies the potential design of physical and chemical properties.
Received: June 24. 1996 [Z9258IE]
German version: Angeic. Chem. 1996. 108. 2805-2809
Keywords: nanostructures - niobium compounds
compounds * titanium compounds
N . Sano, H. Kato. S . Chiko, Solid Stu/e Commun. 1984, 49, 123.
F. Capasso. Physica B 1985, 129. 92.
K . von Klitzing. G Dorda. M. Pepper, Phys. Rev. Left. 1980, 45, 494.
D. C. Tsui, H. L. Stormer, A. C. Gossard, Phys. Rev. Lett. 1982, 48, 1559.
A Cho in Key Pupers in Applied Physics, Vol. I (Eds.: P. S. Peercy. J. M.
Poate). AIP Press. New York, 1994, p. 569; K. Ploog. Angew. Chem. 1988,100.
61 1 : A n p i ’ . Ciwni. l n l . €d. Engi. 1988. 27, 593.
161 K. C. R Chiu. J. M. Poate. L. C. Feldman, C. J. Doherty, Appl. Pl7ys. Lett.
1980, 36. 544.
[7] R. T. Tung. .I.M . Gibson. J. M. Poate. Plzjs. Rev. Left. 1983, 50, 429.
[8] M Noh. J. Thiel, D. C. Johnson, Science 1995, 270, 1181.
[9] A. Koma. K . Yoshimura, Surt. Sci. 1986. 174. 556.
[lo] A. Koma. K. Saiki. Y. Sato. Appl SurJ Sri. 1989, 41/42, 451
[I 11 L. Fister, X. M. Li, T. Novet, J. McConnell, D. C. Johnson, J. Vac. Sci. Techno/.
A 1993. 11. 3014.
[12] C. Riekel, J Solid Stute Chon. 1976, 17. 389.
1131 P. Villars. L. D. Calvert. Pearson’s Handbook o,f trm!allographic Data for
I n t ~ ~ r n ~ e / aPlioses,
I ’ d 4. 2nd ed., ASM International, Materials Park. OH,
USA. 1991
Angrit.. Clieni. In! Ed. Enxl. 1996, 35. Nu. 22
63 VCH
Scheme 1. Three approaches for the construction of tube-shaped molecules
a direct-current electric arc[51and during chemical vapor deposition of carbon-containing gases.r6I Secondly, prefabricated
convex parts can be assembled (see for example the synthesis of
12[collarene] by Stoddart et aI.[’l and of the ribbon-shaped cyclophanes by Vogtle and c o - w ~ r k e r s [ ~ ] We
) ~ ~pursued
a third
approach based on a ring-expanding metathesis reaction,“
which is analogous to the formation of a large bubble by the
combination of two small ones.
Tetradehydrodianthracene (TDDA)“ ‘I 1 was used as the
starting material because its structure is well-suited for the synthesis of a tubelike molecule and because its extremely high
strain energy provides the driving force for a metathesis reaction; the metathesis is therefore directed towards ring expansion. In earlier studies we investigated the general reactivity of
TDDA towards electrophiIes,[lz1nucleophiles,C’31and DielsAlder
Photochemically induced metathesis reactions with ethene, propene, cyclic alkenes, and even with benzene have already been performed.“ The attempted dimerizing
metathesis, however, was achieved only after numerous variations of the reaction conditions finally by photolysis of a suspension of TDDA in benzene with a high-pressure mercury lamp in
a quartz apparatus (Scheme 2).
In homogeneous solution in benzene only very small amounts
of the dimerization product were obtained. The main product is
the known metathesis product with the s o l ~ e n t . ~In’ ~other
solvents like toluene and hexane transfer of hydrogen and ring
opening to bianthryl is predominant. Apparently a suspension
of the reactant In benzene is essential for dimerization of 1.
An X-ray analysis of TDDA 1[l6] was performed to test the
hypothesis of a solid-phase mechanism (Fig. 1 ) . In the crystal
[*I Prof Dr. R. Herges, DipLChem S. Kammermeier
Institut fur Organische Chemie der Technischen Universitit
Hagenring 30. D-38106 Braunschweig (Germany)
Fax: Int. code +(531)391-5388
e-mail: r.herges(u
Prof. Dr. P. G. Jones
Institut fur Anorganische und Analytische Chemie
der Technischen Universitzt Braunschweig (Germany)
This work was supported by the Deutsche Forschungsgemeinschaft and by the
Fonds der Chemischen Industrie (scholarship for S. K.).
Verlunsnrsellschuft mhH, 0-69451 Weinheim,1996
0570-0833/96/3522-2669 $ 15.00+ 2510
Il l
Fig. 2. Van der W a d s surface of 2 ( D 4 J based on the data from an X-ray structure
The “picotube”[2012 consisting of four anthracene units has
an approximate tubular structure with a diameter of 5.4 8, and
a length of 8.2 8, (Fig. 2). All C = C bonds are conjugated and
the 16 e perimeter is antiaromatic. To our knowledge 2 is the
first conventionally synthesized and completely conjugated beltor tubelike hydrocarbon besides the nano- and buckytubes,
which are formed by vaporization of carbon. Unlike typical
aromatic compounds, which have a perfect o r a at most slightly
curved n-plane, the n-plane of 2 is tubular.
In contrast to the crystal structure, semiempirical calculations
of 2 indicate that it has only time-averaged D,, symmetry. The
lowest energy conformation is a D,, structure, which is formed
by a 20” twist of the quinoid double bonds (Fig. 3). Lowering
the symmetry, however, provides a gain in energy of only
6.5 kcal mol-’ (AM1 calculations). The two possible D,,structures should interconvert very rapidly at room temperature.
Freezing of the conformational motion could not be observed a t
temperatures down to - 70 “C.
Scheme 2. Dimerizing metathesis of TDDA.
Fig. 1 . X-ray crystal structure of TDDA 1
the double bonds are oriented in a favorable arrangement for a
[2 2]cycloaddition. Both ~ - p l a n e s [ ’are
~ ] parallel and form an
angle of 64” with the two cyclobutane C-C bonds made during
the cycloaddition. The distance between bridgehead atoms in
neighboring molecules of 1 is 4.31 A and in the upper range of
distances suitable for cycloaddition[’*] (Fig. 1).
One observation does not support the solid-phase reaction of
1: irradiation of solid TDDA in an argon atmosphere does not
lead to an observable reaction. This, however, could be due to
the very strong UV absorption of the product in the range of the
x--TI*transition of TDDA (282 nm), and thus the crystal surface could be “passivated” towards further reaction in the interior. In suspension in benzene the surface of the dimer would be
continuously dissolved and removed. Additionally benzene
probably acts as a singlet sensitizer. The x-x* transition of
TDDA is symmetry forbidden (E,,, = 1270). Since the photolysis is performed in a quartz apparatus, excitation of benzene
followed by energy transfer to TDDA is likely. A triplet reaction
can be excluded because the addition of triplet sensitizers such
as acetone and benzophenone leads almost exclusively to the
formation of anthracene.
The ‘H N M R spectrum with two signals and the 13C N M R
spectrum with only four signals indicates that the metathesis
product 2, at least on time average, should have a very high
( D 4 J symmetry. Besides the M + peak a t m / z 704 there is only
one additional peak in the mass spectrum at half the molecular
weight at m / z 352. Most probably this does not arise from a
fragment but from the aromatic dication of 1. The final proof of
structure was provided by a crystal structure analysis. Unfortunately the crystals of 2 contain large amounts of disordered T H E
which prevented sufficient refinement of the structure ( R ( F )=
0.14). The connectivity of the atoms and the high symmetry of
D,,, however, can be determined unequivocally (Fig. 2) .[‘’I
1% VCH V e r l a g . ~ ~ e s e l l . ~mhH.
c l ~ a ~D-69451 Weinhein?. 1996
Fig 3 . A M I -calculated conformational movement of 2
Picotube 2 is extraordinarily stable and unreactive. Neither
melting nor decomposition were observed at temperatures up to
450 “C. 2 also is completely inert towards rn-chloroperbenzoic
acid and bromine at room temperature. The cylindrical cavity
and the x-orbitals pointing towards the interior suggest that 2
could be used as a n-spherand.[*‘1 Experiments with silver(1)
salts provide preliminary evidence.[”] Poorly soluble 2 suspended in THF can be dissolved by addition of silver(1) triflate.
The FAB mass spectrum of the residue after removal of the
solvent shows peaks at m / z 811 and 813, which correspond
to the mass of 1 : l complexes of 2 with lo7Ag+ and lo9Ag+,
respectively. The 13C NMR spectrum, however, does not exhibit a low-field shift or a carbon-silver coupling. Apparently
there is a fast eauilibrium a t room
temperature in which the solventseparated reaction partners are
Intramolecular cyclization-dehydrogenation of 2 would lead to
the buckytube 3 with a length of
three and a perimeter of eight benzene rings. Experiments aimed at
this target are underway.
OS70-0833:9n!3522-2670 S 15.00 f .2jiO
A I I ~ EClieni.
L ~ . Int. Ed. E n d . 1996. 35. N o . 22
E.yperimmtal Procedure
1 - M.p. 388 C; ' H NMR (400 MHz, CDCI,): d =7.15 (m, 8 H ) , 6.89 (m, 8 H ) ; I3C
NMR(100.6 MHz,CDCI,):6 =152.2(C=C), 147.O(Cq), 125.8(CH,arom.), 124.1
(CH. arom.): IR (KBr. cm-I): i = 3064m, 3037sh. 1566m. 1449s, 747s. 614s;
UV!Vis (CH,CI,): i,,, (c) = 233 (10700), 270 (2500). 282 (1270) nm; MS (70eV):
mi: ( O h ) : 352 (100) [ M i ] . C.H-analysis (C28H16):calc. C 95.42, H 4.58; found C
95.31. H 4.51.
2 : Tetradehydrodiantliracene 1 (60 mg, 0.170 mmol) was suspended in 10 mL of
benzene in a quartr tube and irradiated from the exterior for 10 h with a high-pressure mercury lamp (150 W). The solvent was removed in vacuo and the residue
purified by chromatography with hexane/
dichloromethane over silica gel. After crystallization
from toluene, 2 was obtained as a colorless solid.
Yield: 1 9 m g (32%). M.p. >45O"C; ' H N M R
(400 MHz, CDCIJCS,): d = 7 83 (dd, J = 3.3.
5.7 Hz. 16H. H-2). 7.00 (dd, J = 3.3, 5.7 Hz. 16H,
H-I); I3C NMR (100.6 MHz, CDCIJCS,):
d = 138.90 (Cq3C-3). 134.55 (C", C-4). 129.07 (CH.
C-2). 124.94 (CH. G I ) : IR (KBr, cm-I): G = 3126, 3058. 3023 (m, C-H, arom.),
1632 (w. C=C). 1447 (s. C=C, arom.), 1089 (m). 764 (s, C-H, arom.). 750 (s, C-H,
, = 231 (21000). 257 (27000). 300
arom.). 632 (s); UV,Vis (CH,CI,): i.,,(c)
(15000)nrn. MS(70 V ) . r n / ~ ( % ) 704(100)[Mt],
MS.calc. for C,,H,,: 704.2504. found: 704.2502.
Received: May 28, 1996 [Z91541E]
German version: Angeii-. Chem. 1996, 108, 2834-2836
Keywords: aromaticity
For a recent survey of beltlike and tubelike molecules see: A. Schroder, H.-B.
Mekelburger, F. Vogtle. Top. Curr. Chem. 1994, 172, 180-200.
For a recent review see: a) A. Hardda. Farumushia 1995.31. 1263-1267; P. R.
Ashton. C. 1. Brown, S . Menzer. S. A. Nepogodiev. J. F. Stoddart, D. J.
Williams. C h m . Eur. J. 1996. 2, 580-591.
a ) M R. Ghadiri. K. Kobayashi, J. R. Granja, R. K. Chada, D. E. McRee,
Arigrii.. Cliivn. 1995. 107.76-78; Angaii-. Chem. I n / . E d Engl. 1995,34,93-95;
b) M. R. Ghadiri. Adv. Muter. 1995, 7, 675-677; c) M. Engels. D. Bushford.
M. R. Ghadiri. J. A m . Chem. Soc. 1995, /17. 9151-9158.
H. Meier. K . Miiller, Angew. Chrm. 1995,107.1598-1600; Angew. Chem. Int.
Ed. Dig/. 1995, 34. 1437-1439.
a) S. lijima, Nurure 1991, 354. 56-58; b) S. Iijima, T. Ichihdshi. Y. Ando.
Nutirra 1992,3S6. 776-778; c) For recent review see R. S. Ruoff. Nature 1994.
372. 731 - 732.
K Hcmadi. A. Fonseca, J. B. Nagy, D. Bernaerts, J. Riga. A. Lucas. Svnth.
M e t . 1996. 77, 31 43.
a ) F. H. Kohnke, A. M. Z. Slawin. J. F. Stoddart. D. J. Williams, Angew. Chrm.
1987. W , 941 943; Angen.. Chem. lnr. Ed. Engl. 1987. 26, 892-894; b) P. R.
Ashton, N. S Isaacs. F. H. Kohnke, A . M . Z. Slawin, C. M. Spencer, J. F.
Stoddart. D. J. Williams. ihrd. 1988. 100. 981 -983, and 1988. 27, 966-968.
W. Josten. S . Neumann. F. Vogtle, M. Nieger. K. Hiigele, M. Przybylski. F.
Beer, K. Mullen. Chcm. Ber. 1994, 127. 2089-2096.
For further examples see ref. 111.
a ) G. Schroder. J. F. M. 0 t h . Ewahrdron Lett. 1966, 4083-4088; reviews: b)
G. Mehta. .I Chcm. Educ. 1982, 59, 313--316; c ) G. Kaupp, Houben Wevl,
Methorken der oi-gunwhen Chemie. Photochemre 1. Thieme, 1975, 298-299.
R L. Viavattene. E D. Greene. L. D. Cheung. R. Majeste, 1 . M. Trefonas, J
Am. <'h<wi.So< 1974. 96, 4342-4343.
R. Herges. H Neumann. Liehips Ann. 1995, 1283-1289.
R. Herges, H. Neumann, F. Hampel. Angew. Chem. 1994. 106. 1024-1026:
Angrir. Chrm. In1 Ed Engl. 1994.~33.993-995.
R. Hcrges. S . Kammermeier. H. Neumann, F. Hampel.
Lii,hig.s Anti. 1996, 1795-1800.
S . Kainmermeier. R Herges. A n g w Chem. 1996. 108, 470472. An,@w Chcni. In/. Ed. Engl. 1996. 35. 417-419.
See also ref. [I I]. Crystal data: tnclinic, Pi,u = 6.5047(8).
73.351(8). 7 =72.232(8) . V = 434.09 A'. 2 = 1, i.(Mo,,) =
0.71073 A, T = 100 -C. 2001 Independent reflections were
measured on it Siemens four-circle diffractometer up to
20 = 55 . The structure was solved with direct methods and
anisotropically retined on F 2 (H-atoms riding; program
SHELXL-93. G . M. Sheldrick. Universitit Gottingen). The
final R value ivR(F') was 0.097. with conventional R (,F,) =
0.037: max Ap 0.25 e k ' , S 1.06. The crystallographic data (excluding structure factors) for the structure reported in this paper have been deposited with
the Cambridge Crystallographic Data Centre as supplementary publication
no. CCDC- 179-99. Copies of the data can be obtained free of charge on application to The Director. CCDC. 12 Union Road, Cambridge CB2 lEZ, UK
(fax: Int. code f(l2231336-033; e-mail: teched(
1171 The rr-planes are defined by the four substituents of the bridgehead doubIe
[18] a) V. Ramamurthy, K. Venkatesan, Chem. Res. 1987.433-481; h) M. D. Cohen, G. M. J. Schmidt. J. Chem. Soc. 1964,1996,2000,2014. c) K. Gnanaguru,
N. Ramasubbu, K. Venkatesan, V. Ramamurthy, J: Photochem. 1984, 27.355.
1191 Note added in proof (25.09.96): In the meantime we have obtained a crystal
structure analysis of a 2: 1 complex of silver trifldte with 2 which unequivocally
confirms the D,, structure of 2.
1201 "Picotube" in analogy to the larger and also fully conjugated nanotubes.
1211 a) J. L. Pierre, P Baret, P. Chautemps. M. Armant, J: An? Chem. Soc. 1981,
103, 2986-2988, b) C. Cohen-Addad, P. Baret, P. Chautemps. J.-L. Pierre,
Acta Crwtullogr. Sect. C. 1983,39, 1346-1349; c) H. C. Kang, A. W. Hanson,
B. Eaton, V. Boeckelheide. J Am. Chem. Soc. 1985, 107. 1979-1985; d) T.
Prohst, 0. Steigelmann, J. Riede. H. Schmidbaur, A n g m . Chem. 1990, 102,
1471 -1473; Angeic. Chem. Inl. Ed. Engl. 1990,29. 1397-1399;e) F. Inokuchi,
Y. Miyahdrd, T.indzu. S. Shinkai, ibid. 1995. 107, 1459- 1461 and 1995, 34.
1364-1366; f) J. Gross, G. Harder. F. Vogtle, H. Stephan, K. Gloe, (bid. 1995,
107. 523-526 and 1995, 34, 481-484; g) J. E. McMurry, G. J. Haley, J. R.
Matz, J. C. Clardy, J. Mitchell, J. Am. Chem. Soc. 1986, IOH, 515-516.
Samarium Diiodide Mediated Coupling of
Glycosyl Phosphates with Carbon Radical or
Anion Acceptors-Synthesis of C-Glycosides""
Shang-Cheng Hung and Chi-Huey Wong*
C-Glycosides, which have conformations similar to those of
the parent 0-linked structures,['] have been used as stable carbohydrate mimetics for the study of carbohydrate recognition in
biological systems.['
C-Glycosides are often prepared
through the coupling of anomeric carbocations. radicals, carbanions, and carbenes.[*] Recently. Sinay et al.l9] and Beau et
aI.["] reported that glycosylsamarium(Ir1) derivatives, generated
from glycosyl chlorides or sulfones, undergo a Barbier-type reaction with carbonyl compounds to form C-glycosides. The reactions were considered to proceed through two consecutive
one-electron reductions to form a glycosyl anion intermediate.
Dilithiated D-glucopyranosyl derivatives have been developed
by Kessler and his co-workers.[' ' I The use of a phosphate group
as an acceptor in the initial electron transfer mediated by SmIJ
T H F has already been described for a-cyanophosphates[' and
allylic phosphates.{' 31 Here, we report a relatively simple
method for the synthesis of C-glycosides under very mild conditions by the umpolung coupling of pyranosyl or furanosyl phosphates with a carbon radical or anion acceptor in the presence
of samarium diiodide (Scheme 1).
Anaetr. Chrm.
Ed. En@ 1996. 35. No. 22
<? VCH
Prof. Dr. C.-H. Wong, Dr. s.-c. H u n g
Department of Chemistry, The Scripps Research Institute
10550 North Torrey Pines Road, La Jolla, CA 92037 (USA)
Fax: Int. code +(619)784-2409
[**I We thank Dr. Kap-Sun Yeung and Chun-Chen Lin for supplying some starting
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anthraceneчsynthesis, structure, metathesis, expanding, hydrocarbonic, conjugate, ring, tubelike, full, tetradehydro
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