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Carbanion-Induced Skeletal-Rearrangements From the Dibenzo[a e] cyclooctene to the Indeno[2 1-a]indene Framework.

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Alkoxide addition to the double
of l b in the
synthesis of 7b and 7c is preceded by rapid transesterification to Yb and Yc, respectively, which is >95% complete
before appreciable amounts of 10111 are formed. The
product ratio 10111 depends in the first instance on the
reaction temperature; appreciable selectivities occur below
- 50°C. Complete conversion can only be achieved if the
alkoxide is added in equimolar amounts. The reaction rate
decreases along the sequence 'OMe, "OEt, 'OCH,Ph:
Only 'OMe still adds completely to l b at -78°C; for
"OEt this occurs only down to -50°C (Table 1, No. 7),
and OOCH2Ph does not react with l b below -20°C. At
the same temperature (Nos. 2, 6, 8), the differences in selectivity are small. The reaction proceeds under conditions
of kinetic control; at room temperature, loallla undergo
only transesterification with sodium benzylate, and no exchange of the 3-OMe occurs. The same is true for 1Oc1llc
and sodium methoxide.
The central diol unit in 2a and 2b is ideally suited for
transformation into natural-product derivatives since the
hydroxy groups can be differentiated easily. The terminal
functional groups CH,-O, CH2=CH2, and C0,Me may
be used for chain extension on both sides. The OMe-protecting group in 10a can be removed at a later stage of the
Received: May 11, 1984;
revised: June 18, 1984 [Z 831 IE]
German version: Angew. Chem. 96 (1984) 726
[I] Selected examples: a) R. W. Hoffmann, 8. Kemper, Tetrahedron Lett. 21
(1980) 4883; 22 (1981) 5263; b) R. W. Hoffmann, A. Endersfelder, H.-J.
Zeiss, Curbohydr. Res. 123 (1983) 320; c) P. G. M. Wuts, S. S. Bigelow, J.
Org. Chem. 48 (1983) 3489; d) C. Fuganti, P. Grasselli, F. Spreafico, C.
Zirotti, ibid. 49 (1984) 543, and literature cited therein; e) S. Masamune,
W. Choy, Aldrichim. Acta I S (1982) 47.
[2] Summary of stereodescriptors: D. Seebach, V. Prelog, Angew. Chem. 94
(1982) 696; Angew. Chem. Int. Ed. Engl. 21 (1982) 65.
[3] (R)-la: D. Dumont, H. Pfander, Hefu. Chim. Actu 66 (1983) 815, and literature cited therein; @)-la (from L-arabinose): S. B. Baker, J. Am.
Chem. SOC.74 (1952) 827.
[4] J. Mulzer, A. Angermann, Tetrahedron Lett. 24 (1983) 2843; for the diastereoselective addition of organometallic compounds to l a , see [lb].
151 J. Mulzer, M. Kappert, Angew. Chem. 95 (1983) 60; Angew. Chem. Int.
Ed. Engl. 22 (1983) 63; Angew. Chem. Suppl. 1983, 23.
161 Correct elemental analyses were obtained for all compounds. Further
data for 7c, 8a, and 8c: 7c: m.p.=65-66"C, [a]$ 38.6 (CHC13,c=4);
'H-NMR (CDCla, 60 MHz, TMS): 6=2.48 (dd, J=18 and 3 Hz, 3-H),
2.86 (dd, J = 18 and 7 Hz, 3-H), 3.37-4.0 (m, 5-H), 4.15-4.33 (m, 4-H),
4.47 (s, OCHzBn), 4.57 (br, OH), 7.25 (s, Ph).-8a: m.p.=89-9O0C,
[a]$ -33.1 (CHC13, c=2), 'H-NMR (CDC13): 6=2.70 (d, 5-5 Hz, 3H), 3.07 (br, OH), 3.35 (5, OMe), 3.95 (d, J = 5 Hz, CH,OH), 4.25 and
4.62 (respectively, q, J = 5 Hz,4- and 5 H).-Sc: oil, [a]$ - 13" (CHCI,,
c=2); 'H-NMR : 6=2.65 (d, J = 5 Hz, 3-H), 3.3 (br, OH), 3.85-4.02 (m,
CH20H), 4.17-4.70 (m,OCH2Ph+4-H, SH), 7.25 (m, Ph).
[7] Structural data: C6HI0O1 (146.15), m.p. = 89-90°C, orthorhombic,
P2,2'2], a=4.469(2), b=7.529(4), c=20.93(1)
V=704 A', Z = 4 ,
p..,.= 1.38
~ m - ~MoK,-irradiation
,
(graphite monochromator),
A=0.71069A, 2"<8<42', 481 observed reflections, 447 of which with
1 > 2 u , R=5.34, R,=5.66. o-Scan with 1.8<&<29.3" min-'. Further
details of the crystal structure investigation can be obtained from the
Fachinformationszentrum Energie Physik Mathematik, D-7514 Eggenstein-Leopoldshafen 2, by quoting the depository number CSD 50934,
the names of the authors, and the journal citation.
[8] For the addition of benzylamine to l b , see: H. Matsunga, T. Sakamaki,
H. Nagaoka,.Y. Yamada, Tefrahedron Lett. 24 (1983) 3009.
[9] The Hg(OAc),-catalyzed of benzyl alcohol to chiral Michael systems
also proceeds with high ul-1,2-selectivity: S. Thaisrivongs, D. Seebach, J.
Am. Chem. SOC.105 (1983) 7407.
[lo] T. Greene: Protective Groups in Organic Synthesis, Wiley, New York
1981, p. 15.
A,
Angew. Chem. Int. Ed. Engl. 23 (1984) No. 9
Carbanion-Induced Skeletal Rearrangements:
From the Dibenzo[u,e]cyclooctene to the
IndenoI2,l-ulindene Framework* *
By Dieter Hellwinkel*, Hans-Joachim Hasselbach, and
Frank Lammerzahl
In our studies of peripherally bridged tetraphenylene
derivatives"], we have explored methods of introducing
substituents suitable for further annellation~[~]
by nucleophilic substitution of the bromine atoms of 5,6,11,12-tetrabromodibenzo[a,e]cyclooctene 112].
If 1 is allowed to react with excess organolithium compounds in tetrahydrofuran between - 78 "C and room temperature, not the tetraorganobenzo[a,e]cyclooctenes 2,
products of a simple addition-elimination mechani~m[~.~I,
but only isomers with the indeno[2,1-a]indene framework
are obtained. In this way, methyl- and n-butyllithium afford up to 70% of the 5,5,10,10-tetraalkyl-5,lO-dihydroindeno(2,l-aIindenes 3, 4, whereas with tert-butyllithium
mixtures of the tri- and di-tevt-butyl derivatives 5 , 6 and,
with a large excess of tBuLi, moderate yields of the tri-tertbutyl derivative 5 are obtained. In contrast, with phenyllithium the red-brown 5,10-diphenylindeno[2,1-a]indene 10
is obtained, which is identical with a reference compound
synthesized
using
an
independent
procedure[61
[m.p.=247-248"C, 'H-NMR (CDCI,): 6=6.84 (td, 2H),
6.90 (td, 2H), 7.03 (dm, 2H), 7.24 (dm, 2H), 7.45 (tt, 2H),
7.52 (tm, 4H), 7.67 (dm, 4H)].
Treatment of the phenyllithium reaction mixtures, which
like the others are deeply colored, with ethanolic hydrogen
chloride, iodomethane, or iodobenzene at low temperatures affords the derivatives 7-9 of 5,lO-dihydroindeno[2,1-a]indene.
Br
R
Br
R
d k
a) Alkyl-Li
b) 1. PhLi
2. RX
QJp
Ph
10
5
Ph
3
4
5
6
7
8
9
R
R'
R*
m. p. ["C]
Me
nBu
tBu
tBu
Ph
Ph
Ph
Me
nBu
tBu
H
H
Me
Ph
Me
nBu
H
H
H
Me
Ph
214
154
145
165
286
276
351
The structures of 3 to Y were corroborated by elemental
analysis, and, in particular, by the I3C-NMR spectra,
whose characteristic signals are summarized in Table 1.
[*I Prof. Dr. D. Hellwinkel, H.-J. Hasselbach, Dr. F. Ldmmerzahl
Organisch-chemisches Institut der Universitat
Im Neuenheimer Feld 270, D-6900 Heidelberg 1 (FRG)
[**I This work was supported by the Deutsche Forschungsgemeinschaft, the
Fonds der Chemischen Industrie, and BASF AG, Ludwigshafen.
0 Verlag Chemie GmbH. 0-6940 Weinheim, 1984
0570-0833/84/0909-070S $ 02.50/0
705
Table 1. Selected I3C-NMR data for 3-9 (CDCI,, rel. TMS, &values) [a].
Position 3
5, 10
4a, 9a
4
44.9
54.0 68.6/ 55.1
137.9 140.7 143.21141.7
155.5 155.3 159.0/154.6/
158.9 155.9 154.21151.4
l{
4b,
Sa, 9b
10a
6
5
7
8 [b]
56.3 49.9 52.4/ 52.3
142.8 138.2 142.4/142.3
155.4 152.5 159.2/157.9/
156.8
150.9 151.2
9
61.8
141.4
155.9
154.0
[a] ‘H-NMR (CDCI,, &values): 3 : 1.53 (s, 12H), 7.22 (td, 2H), 7.29 (td, 2H),
7 . 4 0 ( d , 2 H ) , 7 . 4 2 ( d , 2 H ) ; 4 : 0 . 6 5 ( t , 12H),0.71-1.3(m,16H),2.00(t,8H),
7.1-7.4 (m, 8 H ) ; 5 : 1.03, 1.08 (each s, together 18H), 1.28 (s, 9H), 3.59 (s,
IH), 7.00-7.90 (m, 8 H ) ; 6:1.18 (s, 18H), 3.46 (s, 2H), 7.06 (td, 2H), 7.22
(td, 2H), 7.42 (d, 2H), 7.48 (d, 2H); 7 : 4.97 (s, 2H), 7.05-7.20 (m, 6H),
7.20-7.35 (m, 12H); 8 [bl: 1.94, 1.99 (each s, together 6H), 7.0-7.5 (m,
I8H). [b] As a cis/trans-mixture which melts at 240°C.
A preliminary reaction scheme which accounts for all
the products isolated involves initial addition of an Re ion
to 1 to yield 11, which subsequently undergoes transannular addition-elimination to give 1217].Compound 12 could
then react with additional R’ to afford intermediate 13,
which can react in various ways: with alkyllithium, further
substitution occurs to furnish the tetra-, tri-, and dialkyl
derivatives 3 - 6. Phenyllithium can either attack a bromine atom to form, via elimination, 10, or can undergo a
double halogen-metal exchange affording the dianion
14[81,which can be trapped with electrophiles to give
7-9.
R
Rr
Ph
[5] G. Reiff, Dissertation, Universitat Heidelberg 1970.
161 K. Brand, Ber. Dfsch. Chem. Ges 45 (1912) 3071.
[7] Cf. A. G. Anastassiou, H. S. Kasmai, D. Hauger, J. Chem. Sac. Chem.
Commun. 1981, 647.
[S] Comparable dianions: 1. Willner, J. Y. Becker, M. Rabinovitz, J. Am.
Chem. Sac. 101 (1979) 395; T. Uyehara, T. Honda, Y. Kitahara, Chem.
Lett. 1977, 1233.
Stereochemical Evidence Supporting the Intermediate
Mechanism of Dihalocarbene Addition**
By Eckehard V. Dehrnlow* and Roland Kramer
Singlet halocarbenes generally react with alkenes via cisaddition, which is often envisaged as a concerted (onestep) process. More recent kinetic data on the additions of
CCI2, CBr2, and C6H5CI have nevertheless been interpreted in terms of reversible, intermediate formation of a
charge-transfer complex[’-i1.These results corroborate the
two-step mechanism proposed by SkeN et al. for CX2 as
early as 1956[41.Products which demand a mechanism involving an intermediate arise, to the best of our knowledge, in halocarbene reactions’’’ in only three
In
particular, for the reaction of trans-cyclooctene 1 with
CBr2 both the stereospecific formation of 3bI9]and the formation of a large amount of 3b in addition to a little 4bf8I
were reported in 1970. According to [8], partial isomerization 1 +2 occurs under the reaction conditions.
With the aid of 300 MHz ‘H-NMR spectroscopy it is
easy today to test the purity of trans- and cis-cyclooctene 1
and 2“01,respectively, as well as of adducts 3a, b and 4a,
b“’]. Mixtures of 3 and 4 can also be analyzed using capillary gas chromatography[”I. We found that after 10 min
(+ )-1 has reacted completely and stereospecifically with
CCl, generated by phase transfer catalysis (PTC) (conc.
NaOH/HCCl,/methyltrioctylammonium chloride (Aliquat 336)) to afford (+)-3a. In the analogous reaction with
HCBr,/EtOH (trace) a mixture of 3b/4b (92 :8) is formed
after 10 min (30-40% conversion); furthermore, a cis/transisomerism of the alkene occurred ( 1 : 2 = 8 :9). After
30 min (80-90% conversion), 3b and 4b are present in the
ratio 77 :23, and the unreacted alkene consists to ca. 90%
of 2. Upon being stirred with tetrabutylammonium bromide/NaOH or with Aliquat 336/NaOH in CD2C1,, transcyclooctene 1 does not rearrange into 2. Under these reaction conditions, 3b is also stable, and the course of the
reaction is not affected by atmospheric oxygen
In only one instance have we observed nucleophilic substitution at 1 with retention of the skeleton: reaction of 1
with copper(1) cyanide in N-methylpyrrolidone gives rise
to 30% 5,6,11,12-dibenzo[a,e]cyclooctenetetracarbonitrile2
(R=CN) [m.p.=35O0C, vcN=2210 cm-’I, whose symmetrical ’H-NMR signal pattern (6,,,= 7.59, 6BBr=
7.48) substantiates that the framework has not undergone rearrangement.
In the meantime, we have obtained evidence which indicates that reactions of 6 with less polar Grignard compounds and organolithium compounds in less polar solvents such as diethyl ether also proceed with retention of
the skeleton.
0
lJ
0
2
a, X
Received: May 10, 1984 [Z 826 IE]
German version: Angew. Chem. 96 (1984) 713
[I] D. Hellwinkel, G. Reiff, V. Nykodym, Justus Liebigs Ann. Chem. 1977,
1013; D. Hellwinkel, G. Haas, ibd. 1979, 145.
121 M. P. Cava, M. J. Mitchell: Cyclobutadiene and Related Compounds, Academic Press, New York 1967, p. 197.
[3] H.-J. Hasselbach, Diplomarbeit, Universitat Heidelberg 1979.
[4] B. J. Wakefield: The Chemistry of Organolithium Compounds, Pergamon,
Oxford 1974, p. 155f.
706
0 Verlag Chemie GmbH, 0-6940 Weinheim, 1984
IN, -
-+
3
IN, 4
= C1;
b, X = 13r
[*I Prof. Dr. E. V. Dehmlow, DipLChem. R. Kramer
Fakultat fur Chemie der Universitat
Universitatsstrasse 25, D-4800 Bielefeld (FRG)
[**I This work was supported by the Deutsche Forschungsgemeinschaft and
by the Fonds der Chemischen Industrie.
0570-0833/84/0909-0706 $ 02.50/0
Angew. Chem. In(. Ed. Engl. 23 (1984) No. 9
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skeletal, framework, cyclooctene, indeno, rearrangements, induced, dibenzo, indene, carbanion
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