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Azaoctabisvalenes.

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Reaction of the crude diol 12 with phosphorus tribromide
leads instantaneously to a semibullvalene precursor, the
exo, e m dibromide 19. Reductive dehalogenation of 19 with
magnesium, in a reaction monitored by N M R spectroscopy,’71 generates 3.[’] A chemical structural proof for 3 is
provided by its reaction with bromine, which results in reformation of 19[3,91
(Scheme 3).
E E
19
Scheme 3. a) PBr,, CHCI,, 0 ’C. 35 % based on 10. h) Mg, THF, quant. c) Br,.
CCI,. -78’C. 63%.
The attractivity of semibullvalene is due to its particularly
strained divinylcyclopropane structure, which allows a degenerate Cope rearrangement to occur with extremely low
activation energy. Attempts to further accelerate the
Cope rearrangement have involved
and
the introduction of nitrogen
15] but the extreme
case of a “bishomoaromatic” ground state has not yet been
attained. Simple bridging of the semibullvalene framework,
as in 20a,[’61leads to nonequivalence of the valence isomers
20a/20b. In the first doubly bridged semibullvalene 3, the
Cope rearrangement of which is again degenerate, the two
bridges should increase the strain in the ground state more
than in the transition state, thus further lowering the activation barrier of the Cope rearrar~gement.~”]
In a 13CN M R
20a
(41 All new compounds gave correct elemental analyses Selected spectroscopic data for 2 : ”C NMR (50 MHz, [DJTHF): 6 = 18.4 (CH,), 52.4
(OCH,). 57.0 (C-13.14). 116.5 (C-2.8). 119.7 (C-4.6.10.12). 131.9 (C1,3,7,9), 155.7 (C-5,ll). 164.7 ( C = O ) ; MS ( m / z ) : 390 (100%. M e ) . I R
(KBr): d = 2940,2870,1705, 1235,755 cm-’. UV (CH,CIZ):2 = 244 nm
(Igt:5.30). 310 (5.46). 411 (4.63).
(51 E. Vogel. H. Konigshofen, K. Miillen, J. F. M. 0 t h . Angrw. C‘hem. H6
(1974) 229; Angen. Chem. lnt. Ed. EngI. 13 (1974) 281.
(61 K. Hafner, V. Kuhn, Angew. Chem. YR (1986) 648; Angiw. <’hem. Inr Ed.
EngI. 25 (1986) 632.
[7] B. Dull, Diplomurhrit, Universitit Mainz 1987.
(81 3: Colorless, air-sensitive solid: ‘H NMR (200 MHz. [D,]THF): f = 1.10
(CH,), 1.222, 1.224 (OCH,CH,), 2.85 (H-2.4,8,10), 4.08, 4.13 (OCH,).
” C NMR (50 MHz. [DJTHF): b = 9.6 (C-CH,), 14.26. 14.31
(OCH,CH,). 30.0(C-2.4,8.~0).61.8(C-3,9), 62.1 (OCH,). 70.X(C-12,13).
100.4 (C-l,5.7.11), 121.4 (C -6.14). 170.6 ( C = O ) . MS ( m / ; ) : 568 (15%.
.Me). IR(KBr): a = 2984. 1734, 1275, 1261, 750cm-’. Compound 3 is
stable in degassed ether solvents even at 80°C; exposure to oxygen or
moisture, however, results in rapid decomposition.
[9] L. A. Paquette, G. H. Birnberg, J. Clardy, B. Parkinson. J. Chern. Soc.
Chrm. Commun. 1973,129: R. Askani, H. Sonmez, Tc./ruhedron Lrtl. 1973,
1751.
[lo] R. Askani, M. Littmann, fiwuhedron Lert. 23 (1982) 3651.
[ t l ] H. Quast. 1. Christ, Y. Gorlach, W. von der Saal. Tetmhcdrnn L m . 23
(1982) 3653; H. Quast, J. Christ, E.-M. Peters, K. Peters. H. G. von
Schnering, Chem. Ber. 1fX (1985) 1154.
I121 L. S . Miller, K. Grohmann, J. J. Dannenberg, L. Todaro, J. Am. Chwn.
Soc. 103 (1981) 6249.
[I31 D. Paske, R. Ringshandl. I. Sellner. H. Sichert, J. Sauer. Angcw. Chm7. Y2
(1980) 464; I.Sellner. H. Schuster. H. Sichert, J. Sauer, H. Niith. Chem.
Ber. 116 (1983) 3751.
[14] R. Gompper, H. Noth, P. Spes, Terruhedron Le//. 29 (1988) 3639.
[l5] C. Schnieders. H.-J. Altenhach. K. Mullen, A n g w . Chem. Y4 (1982) 638:
Angew. Chem. lnr. Ed. Engl. 21 (1982) 631; A n g e w Chem. Suppl. 1982,
1353.
[16] L. A. Paquette, R. L. Burson, Terruhedron 34 (1978) 1307, and references
cited therein.
[I71 R. V. Williams, H. A. Kurtz, J. Org. Chem. 53 (1988) 3626.
(181 A shift difference of 4500 Hz was assumed for the signals of C-l and C-7
in the slow exchange domain. This value corresponds to the shift difference
for C-2 and C-4 of unsubstituted semibullvalene. A value of - 180 C was
chosen for the coalescence temperature T,. Based o n experience with other
semihullvalenes 1191 with respect to the temperature range in which dynamic processes result in Iine-shape changes, however, T, i s presumably
considerably lower.
[19] D. Moskau, R. Aydin, W. Leber. H. Giinther. H. Quast. H.-D. Martin. K.
Hassenruck, K. Grohmann, Chrm. Eer., in press. We thank Prof. Giinrher
and Prof. Quust for providing US with unpublished data.
[20] The fastest degenerate Cope rearrangement (AG:,, = 13.0 kJ mo1-l) was
observed for 1.5-dimethylsemibullvalene-2.6-dicarbonitrile.
20b
X = e.g.. CH,,(CH,),.(CH,),,O.S.
NR.CH,-O-CH,,CH,~S-CH,
measurement [50 MHz, dimethyl ether:[D,JTHF ( 5 : l)], the
averaged signal for the terminal centers C-1,5,7,11 of the
ally1 systems in 3 revealed no significant line broadening even
a t - 160 “C. Therefore, the Cope rearrangement is rapid on
the N M R time scale even at this temperature. From the
Eyring relationship, an upper limit of ca. 15 kJ mol-’[’81
for the free energy of activation AG9: can be estimated for 3;
this value is considerably less than the value for semibull201
valene AG& = 23 kJ molReceived: April 24, 1989 [Z 3304 IE]
German version: Angew. Chem. 101 (1989) 1375
CAS Registry numbers:
2. 122425-03-0; 3, 122425-04-1; 4, 791 50-94-0; 5, 122442-94-8; 6 , 122442-95-9;
7. 122442-96-0; 8, 122442-97-1; 10, 122425-05-2; 11, 122425-06-3: 12, 22242507-4; 13. 122425-08-5; 14, 122425-09-6; 15, 122425-10-9; 16. 122442-98-2; 17,
122425-11-0. 18. 122425-12-1 ; 19, 122425-13-2; potassium diethyl malonate,
37892-24-3.
[I] U . Weiss. J. M. Edwards. Tetruhedron Leri. 196R, 4885; S . H. Bertz. J. M.
Cook, A. Gawish, U. Weiss, Org. Synrh. 64 (1986) 27.
121 The contigurations could be determined by a homonuclear NOE experiment.
[3] H. Kohnz, M.Krauss, K. Mullen. to be published.
A n g c u . C % i w . In/. Ed. Engl. 2H (1989j N o . I 0
0 VCH
Azaoctabisvalenes **
By Bj6rn Trupp, Huns Fritz, and Horst Priizzhuch*
Our syntheses of the preparatively challenging and theoretically intriguing carbo- and heterocyclic all-cis-tris-cs-homobenzenes A and C are based ultimately on benzene[’] and
substituted cycloheptatrienes,f21respectively. The readily accessible intermediates involved in these syntheses provided
the main impulse for our work on the highly strained
octabisvalenes B and D.[31Here we describe the synthesis of
diazaoctabisvalene (B, X = N ) and azaoctabisvalenecarbonitrile (D, X = N , R = CN). Like the framework of the
still unknown tetraaza analogue 3/41 the heterocyclic frameworks 1 and 2, with their azabicyclobutane subunits.[51
should have a strain energy o n the order of that
[‘I Prof. Dr. H. Prinzhach. Dip!.-Chem. 8 . Trupp. Prof. Dr H. Frit7
[**I
Chemisches Lahoratorium der UniversitPt.
Institut fur Organische Chemie und Biochemie
Alhertstrasse 21, D-7800 Freiburg (FRG)
This work was supported by the Deutsche Forschungsgemeinschaft, the
Fonds der themischen Industrie. and BASFAG. We would like to thank
Dr. D. HunkLr and Dr. J. Worrh for the N M R and MS analyses, resprctively.
Yc.rlugsge.sell.whufi mhH, 0.6940 Wrinheim, 19x9
0570-0833/HYj1010-134S $02.SCJ/O
1345
A
Sr
B
ar
4
N3
C
Nb
D
5
OR ORk
N
3
OROR OR
OR
5
1
2
3
'
( E , = 154 kcal mol- C 3 ] ) calculated for the recently reported (CH), parent framework B (X = CH).@I
A key intermediate in the synthesis of cis-trioxide A
(X = 0) is the anfi-cis-dibromoepoxycyclohexene 4."] Its
facile conversion to the muco-diazido- and muco-diaminodideoxyinositols 5 a and 6a, respectively, has been described.['* w The use of suitably functionalized derivatives
reduces the preparation of 1 to the intramolecular substitution of the four O R leaving groups trans-vicinal to the
N functions (4 -P 5 (6) -P 7 -+ 8 10 --t 1). A potential complication was the competing cyclization of monoaziridine
7 @ 7' to 1,4-bis(aziridine) 9.
Also uncertain was whether 1, with its highly reactive
C4(8)-N bonds and acidic C4(8) hydrogens, would withstand the conditions required for the final bond formation,
which, according to calculations, involves a significant increase in strain. After unsatisfactory results with the diamino
tetraesters 6b,c, we focused our efforts on the diazido
tetramesylate 5b.l9] Compound 5 b was first treated with
LiAIH, under the conditions used for the preparation of
czs-tris(imine) A (X = N H ) (THF, 10 + 25 "C, 2 h).f''] In
agreement with the explanation given there for the selective
course of the reaction, we were unable to obtain satisfactory
results, despite wide variation of the reaction conditions. By
contrast, treatment of 5 b with triphenylphosphane/acetonitrile" afforded the unstable bis(aziridine) 8 a in 65-70 o/o
yield (20-mmole scale) as a crystalline solid; the intermediate
monoaziridine 7 was not isolated. Repeated, careful monitoring of the reaction (TLC, 'H N M R ) revealed no evidence
of bis(aziridine) 9 a. This competing reaction, which adversely affects the synthesis of the analogous carbocyclic compounds,[* is presumably suppressed by the enormous repulsion of the nitrogen lone pairs oriented in an endo, endo
fashion in the boatlike transition state leading to 9a. According to the ' H N M R spectrum (cf. Fable I)8a(b,c) has C,
symmetry at room temperature; this reflects the equihbrdtion between the equivalent 5e,6a and 5a,6e half-chair conformations.
Owing to the relatively weak acidity of the aziridine N
protons, which engage in hydrogen bonding, very strong
bases are required for the two deprotonation steps leading
from 8 a to 1. Therefore, a potentially competing reaction
was p-elimination to give 11. The best result so far has
been achieved by treating 8 a (2-3 mmol) with 2.2 equivalents of nBuLi/THF ( - 78 + + 25 "C). The unstable, ambiphilic, volatile C,H,N, pentacycle 1 (Z-3,7-diazapentacywas easily isolated as a pure
cIoI5.1 .0.02,4.03*5.06.8]o~tane)
crystalline solid in 45- 55 YOyield by ether extraction of the
solid residue (containing 1 as the only monomeric compo-
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7
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Verlugsgesell.yrhafimhH. D-6940 Weinheim. 1989
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12
nent according to T L C and ' H NMR). Attempts to obtain
the tetracyclic intermediate 10 by use of ca. 1 equivalent of
base provided, in addition to starting material (ca. 18 %) and
traces of 1, mainly polymeric material along with ca. 3 Yo of
the 1,4-dihydro-I ,4-diazocine 121'31derived from the cis-diaza bis-c-homobenzene 11; according to the 'H N M R data,
12 is planar-diatropic. The mono-N-"anion" derived from
8a is presumably stabilized by an internal hydrogen bond,
only the bis-N-"anion" cyclizing via 10 to 1. Control experiments showed that, under the conditions used here, I is slowly metalated at C-4(8) and thereby slowly lost as polymer.
Crystalline 1 exhibits high thermal stability; it sublimes upon
heating above ca. 95 "C and melts (on a preheated hot plate)
at ca. 136 "C with decomposition. In the 'H and I3C N M R
spectra (Fig. I), the two signals are shifted downfield relative
to those of the C,H,
the "C,H coupling constants differ only slightly, whereas the H,H coupling constants (determined for 1 by spectral simulation) and I3C, 13C
coupling constants differ significantly. The *Nshift, mea-
0570-0833~89~1010-1346
R 02.5010
A n g w . Chem. In!. Ed. Engl. 28 (1989) No. 10
Table 1. Physical data for selected compounds.
( 1 ~.2a.4a.5~,6~.7a)-3,8-Benzoyl-3,8-diazatricyclo[5.
1.0.02~4]octane-5,6-d~yl
bismethanesulfonate 8 c : m.p. 182-183°C (CHCiJether); 'H NMR (CDCI,):
6 = 8.04 (m. 4u-H), 7.60 (m,2 p - H ) , 7.46 (m,4m-H), 5.37 (m, 5-.6-H), 3.41
(m, I-.2-H). 3.25 (s. 2 CH,). 3.23 (hrm, 4-,7-H)
afford a nearly quantitative yield of oxadiazapentacycle 15;
triazapentacycle 16 is likewise obtained from 14d and benzaldehyde.
7-AcetyI-3,7-dia~atetra~yclo[4.1.1.0~~~.0'~~]o~tan-X-yl
acetate 13c. m.p.
118- 120 C (suhl.); ' H NMR (CDCI,): 6 = 5.01 (dd. 8-H). 4.51 (m, I-H)*,
4.42(m.6-H)*.3.54(dd.4-H),3.23(m,2-H)**,3.18(m,5-H)**,2.19(s,CH,),
2.13 (s. CH,): J , , 8 z 4.5, J,+ % 1.5. J4.5 % 1.5, J6.8 % 4.5 Hz; "C NMR
(CDCI,). 0 = 174.8 (C=O). 170.4(C=O), 71.O(C-8),62.8(C-l)*. 60.6(C-6)*.
56.4 (C-2)**. 55.9 (C-5)**, 38.5 (C-4). 20.7 (CH,), 19.9 (CH,); MS (CI. isohutane): 111': 209 (,we+ 1 . 100%). 208 ( M e , 5 % ) etc.
5-Benz~l-l0-phenyl-1.5.9-tr~azapentacyclo[5.3.0.0z~b.03~9,04~8]decane
16: oil;
' H NMR(CDCI,).6= 7.2-7.5(m,10H),4.78(s,lO-H),4.26(m,4-,6-H),4.1X
(m. 7-.X-H). 3.92 (m. 2-.3-H). 3.31 (s. CH,); " C NMR (CDCI,): 6 = 137.6.
134.9 (2C).128.7, 128.5. 128.3. 127.8, 127.6, 127.5 (10C). 95.4 (C-lo), 70.2
(C-7.A). 6X.X (C-2.-3), 65.0 (C-4.-6). 52.5 (CH,): MS (CI, NH,): mi; 302
( M a + 1, 100%). 301 (Ma. 2%). etc.
DL-(1rx.h?.7a)-Z-3-Cyano-X-azatetracyclo[5.1
.0.02~4.03~5]o~t-6-yI
methanesulfonate21 b: dec. > 105 'C(rnethanol/ether); 'H NMR([D,]pyridine): 6 = 5.29
(d. 6-HL z 3.X5 (hrs, N-H). 3.39-3.58 (m. 2-,5-H), 3.45 (s, CH,), 2.97 (dd.
4-H).Z35~m.1-.7-H):J,.,=3.0,J,,,=3.0.J,,=3.5,J,.,-OHz
X-Ben~yl-2.8-dia~atetracyclo[4.3.0.03~~.O4~']nonane-5-i~ndu-carhonitrile
26:
m.p. 87 C (ether): ' H NMR (CDCI,): b = 7.2-7.4 (m.5H). 4.67 (m, 7-H),
4.48 (m.9-H), 3.80 (m,l-,3-H), 3.34 (s. CH,). 2.91 (s, 5-H), 2.78 (rn. 4-.6-H),
1.99 (hr.s, N-H: JI,(,
% 3.5. J ,
% 2.5, J4.1z 2.5. J,,9 % 2.5 Hz; I3C NMR
(CDCI,). 6 = 137.4. 128.8, 128.6, 127.6 (6C). 122.2 (CN), 77.5 (C-9), 75.0
(C-7). 61.4 (C-1.-3), 52.3 (CH,), 43.1 (C-4.-6), 22.2 (C-5); MS (EI. 70 eV): mi;
237 ( M a . 2%). 91 (C,HY, 100%). etc.
sured for the first time for an azabicyclobutane, deviates
considerably from that of a ~ i r i d i n e . " ~ ]
~ ~ ~octaCompound 1 behaves like a z a b i c y c l o b ~ t a n e sand
bisvalenesf3.61toward nucleophiles (I -mmole scale): ZnS0,catalyzed addition of water leads, via the nonobservable
30.5
(2.86
CH2C6H5
16
15
A mixture of epimeric trans-dioxatris-o-homobenzenecarbonitriles 17,r21which has proved useful for syntheses in
the C series,"] is a readily accessible starting material for
monoazaoctabisvalenes 2. Compound 17 is sufficiently
acidic at C-9 to be deprotonated without affecting the epoxide functions and to be regioselectively cyclized (three-membered ring formation) to 18 (0.15 M scale, 1 equiv. lithiumbis(trimethylsilyl)amide/THF, 0-20 "C, 50-60%; m.p.
135-136"C, J l , 2 z 3.5, J , , , z 4, J2., z 3.5, J2,S z 3.5,
J4, z 3.5 Hz). In the reaction of 18 (50 mmol) with sodium
azide/MgSO, ( 5 equiv., H,O, 40 "C, ca. 5 d)-substitution a t
C-4 does not compete- the product (90-95 YOoverall yield)
consisted of a mixture of azidodiols 19a (78%) und 20a
(7 YO)along with three (characterized) diazides arising therefrom (in toto 5- 10 YO):the main components could be sepa-
2.86)
CN
248.5
117.5
N E C
22
17
18
19
20
21
22
22.6
1.82
(3.04
1.66
2.78
2.19
2.99
1.96
2.76)
Fig. I . Selected spectral data for 1 and 22(in [DJhenzene and, in parentheses.
CDCl,) 1: J , , 2 = 4.65, J L =~ 4.41, J l , 8 = 1.40 Hz; JCI,H
= 168, .7c4,H
= 209.
J c l . c 8 = 29.2. J N . I H z 8 Hz.MS(EI,70eV):m/z106(Me,3%),52(100%).etc.
22: J t , :
4. J,,x z 3, J,,& 2 1.5 Hz; J C , , , , = 164, JC2,H
= 170, Jcl,li
= 209.
J,,.,=212Hz.MS(EI.70eV):m/~130(Me,21%),129(Me-l,l00%).etc.
13a, to oxadiazatetracycle 14a (which, in water, is complexed with Z n Z Qaccording to ' H NMR). Similarly, reaction with the nucleophiles Na,S (tBuOHI50 OCjl d) and benzylaminejBF, (tBuOHI50 "Cjl d) selectively leads, via
13d/e, to the analogous thiadiaza- and triazatetracycles
14b(c) (ca. 90Y0)and 14d (ca. 8S%), respectively. The piperazine boat in tetracycles 14 is ideally suited for transannular
N , N bridging. Thus, 13c, prepared by treatment of 1 with
acetic anhydride, reacts with weak bases (NH,, Na,CO,) to
RI H
SOZCHg
rated without material loss by flash chromatography. The
bismesylates 19 b/20 b, prepared under standard conditions
in 85-90% yield, can be converted into the tetracyclic
aziridine 21 b (70-85%) under the conditions used for 5 b
(1 0 mmol, triphenylphosphane/THF). Cyclization of 21 b to
22 proceeds under the optimized conditions found for 1
( 5 mmol, 1.05 equiv. nBuLi/THF, - 78 + + 20 “C) without
any competition by the base-induced reactions typical of
bicyclob~tanecarbonitriles~‘
51 and azabicyclobutanes. Trituration of the crude product with ether affords a practicaliy
quantitative yield of crystalline 22 (Z-3-azapentacyclo[5.1.0.02~4.03~5.06~8]octane-7-carbonitrile),
which remains
unchanged up to its melting point (128 “C). The N M R data
(Fig. 1) are characteristic for cyanocyclobutane and azabicyclobutane moieties.
23
H
24
[7] J. Schubert. R. Keller. R. Schwesinger. H . Prinzbach, Chenr. Ber. 116
( I 983) 2524.
[XI B. Trupp, Dtsserrurmn, Universitdt Frciburg 1989.
[9] The new compounds were characterized by their spectra (‘H N M R (250.
400 MHz), ”C N M R (100.6 MHz), IR, MS) and by elemental analysis
(Table 1).
[lo] R. Schwesinger. M. Breuninger. B. Gallenkamp, K.-H. Muller. D. Hunkler, H. Prinzbach, Chem. Ber. 113 (1980) 3127.
[ I l l P. Pochlauer. E. P. Muller. Helv. Chrm. Acta 67 (1984) 1238, and references cited therein.
[I21 W.-D. Braschwitz, C. Rucker, H. Fritz, H. Prinzbach, manuscript in preparation; cf. W.-D. Braschwitz, T. Otten, C. Rucker, H. Fritz, H . Prinzbach,
Angew. Chem. 101 (1989) 1383; Angew. Chem. In[. Ed. Engl. 28 (1989)
1348.
[13] M. Breuninger, R. Schwesinger. B. Gallenkamp, K.-H. Miiller, H. Fritz,
D. Hunkler. H. Prinzbach. Chem. Ber. 113 (1980) 3161: M. Fletschinger,
B. Zipperer, H. Fritz, H. Prinzbdch. Terrahedron Lert. 28(1987) 2517; H. J.
Allenbach. H. Stegelmeier, E. Vogel. ihid. 1978, 3333.
[14] G. J. Martin. M. L. Martin, J.-P. Gouesnard: I5N-NMK Spectroscopy,
Springer. Berlin 1981, p. 115.
[IS] K. H. Hall. E. P. Blanchard, Jr., S. C. Cherkofsky, J. B. Sieja, W. A. Sheppard. J. Am. Chem. Soc. 93 (1971) 110.
Stabilized cis-Tris-o-homobenzenes:
Syntheses, [a2+ 02 + 021 Cycloreversions**
H
By WolJ1Dieter Braschwitz, Thomas Otten,
Christoph Riickev,* Hans Frilz, and Horst Prinzbach *
CH*-C~H~
25
26
Saponification of 23, obtained by treatment of 22 with
acetic anhydride, leads “directly” to oxaazapentacycle 24:
reaction of 22 with Na,S (CH,Cl,/tBuOH, reflux) and with
benzylamine/BF, (CH,Cl,/tBuOH, 50 “C) gives heterocycles 25 and 26, respectively (55-60%, not optimized).
Received: April 28, 1989 [Z 3314 IE]
German version: Angew. Chem. 101 (1989) 1381
CAS Registry numbers:
1,122846-98-4; Sb, 122847-01-2; 7,122847-02-3; 8a. 322873-97-6: 8c, 12287400-4; 10, 122847-03-4; 11, 122847-04-5; 13c, 122847-05-6; 14a, 122847-06.7;
14b. 122846-99-5; 14d, 122847-00-1; 15,122847-07-8; 16,122873-99-8; (2)-17,
122921-39-5; (21-18, 122847-08-9; (f)-19a, 122847-09-0; ( + ) - l 9 b , 12287398-7; ( t ) - 2 0 a , 122847-10-3; ( i ) - 2 0 b , 122841-13-6; ( t ) - 2 1 b, 122847-11-4;
(2)-22, 122847-12-5; 24. 122847-14-7; 25, 122847-15-8; 26. 122847-16-9; A.
52851-26-0: PhCHO, 100-52-7.
[I] R. Schwesinger. H. Fritz, H. Prinzbach, Chern. Ber. 112 (1979) 3318, and
references cited therein.
[2] 8 . Zipperer. K.-H. Muller, B. Gallenkamp, R. Hildebrand, M.
Fletschinger, D. Burger. M. Pillat, D. Hunkler. L. Knothe, H . Fritz, H.
Prinzbach. Chem. Ber. 121 (1988) 757, and references cited therein.
[3] H. Bingmdnn, Dissertation, Universitit Freiburg 1978; C . Riicker. H.
Prinzbach, Angeir. Chem. 97 (1985) 426; Angcw. Chrm. In/. Ed. Engl. 24
(1985) 41 1 ; C. Riicker, H. Prinzbach, H. Irngartinger, R Jahn, H. Rodewald, Tetrahedron Let/. 27 (1986) 1565; T. Netscher, R. Schwesinger, B.
Trupp. H. Prinzbach, ihid. 28 (1987) 2115; D.-R. Handreck, Disserrurion,
Universitit Freiburg 1989.
[4] R. Krieger, Dipiomarheii, Universitit Freiburg 1989.
[5] A. G. Hortmann, D. A. Robertson, J. Am. Chem. Soc. 89 (1967) 5974;
A. G. Horlmann, J. E. Martinelli, Tetruhedron Letr. 1968,6205;W. Funke,
Angew. Chem. 81 (1969) 35; Angew. ChPm. 1ni. Ed. Engl. 8 (1969) 70; W
Funke, Chem. Ber. 102 (1969) 3148; J. L. Kurz. B. K. Gillard, D . A .
Robertson. A. G. Hortmann, J Am. Chrm Soc. 92 (1970) 5008: A. G.
Hortmann, D. A. Robertson, ihid. 94 (1972) 2758; R. Bartnik. 2. Cebulska, A. Laurent. Tetrahedron Lett. 24 (1983) 4197: B Mauze. ihid. 25
(1984) 843; S. Cdlet, H. Alper, ihid. 27 (1986) 2739; R. Bartnik, 2. Cebulska, A. Laurent, B. Orlowska, J. Chem. R i x 1986, 5.
161 C. Riicker, Chem. Bur. 120(1987) 1629: C . Riicker, B. Trupp. J. Am. Chrm.
Sor. 110 (1988) 4828: C. Riicker, H. Fritz, M a p . Reson. Chem. 26 (1988)
1103.
1348
c>VCH Verlagsgesellschuft mhH, 0-6940 Weinheinz, 1989
Extensive variation of the X, Y, and Z positions of the
carbo- and heterocyclic cis-tris-o-homobenzenes 1 is of interest from both mechanistic and preparative points of
view.”] Such carbocyclic frameworks have so far been
rare1’. 3 1 - in part because of their inherent steric properties
and their pronounced tendency to undergo [o2 + 0 2 + 021
cycloreversion (estimated/calculated E, value for the still
unknown C,H,,
framework 3 (R = H), 24-28/37
kcal mo1-’[4-61). Triple oxirane + aziridine and oxirane --t
thiirane transformations, starting from the readily accessible
cis-benzene trioxide 2, provided us with an efficient
approach to compounds I , X,Y,Z = N R or S.[I1 However,
the analogous construction of carbocyck frameworks
(2 --* 3) by triple oxirane --t cyclopropane transformation
met with severe complication^.^^^ Here we describe an efficient synthesis, based on 2, of 3,6,9-tris-acceptor-substituted
cis-tris-o-homobenzenes 3. This special kind of substitution
should provide kinetic stability and facilitate the transformation of 3 to the ring-expanded compound 4 and, still more
important, to bridged structures of the diademane type 5
(X = CH)147 and the semiregular Archimedian polyhedron
6 (X = CH, “truncated t e t r a h e d r ~ n ” ~ ’ ] ) . ~ ~ ]
The synthetic pathway shown in Scheme 1 is based on the
following findings and assumptions: (1) The starting material, scyh‘o-tripropargyltriol 7 b (see Table I), was obtained in
60-65% yield by triple epoxide opening of trioxide 2 with
the reagent [(iPr),SiC = CCH,(2-thienyl)C~(CN)Li,l[~~
to
give 7 a followed by de~ilylation.[~.
‘I (2) Tritosylate 7 c (allequatorial) preferentially gave elimination products upon
treatment with basesc3,‘ I 1 However, elimination reactions
should be suppressed by restricting the CH,R1/OR2 sub[*] Prof. Dr. H. Prinzbach, Dr. C. Riicker, DipLChem. W.-D. Brdschwitz,
DipLChem. T. Otten, Prof. Dr. H. Fritz
Chemisches Laboratorium der Universitit.
Institut fur Organische Chemie und Biochernie
Albertstrasse 21, D-7800 Freiburg (FRG)
[**I This work was supported by the Deutsche Forschungsgemeinschaft, the
Fonds der Chemischen Industrie, and BASF AG. We would like to thank
Dr. D. Hunklur and Dr. J. W&h for the N M R and MS measurements,
respectively.
0570-0833/8911010-1348.%
02.SOiO
Anxew. Chem. I n ! . Ed. Engl 28 (1989) No. 10
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