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Nickel-Catalyzed Cyclodimerization of 2-tert-Butyl- and 2-Trimethylsilyl-1 3-butadiene.

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[I21 J. N . Hay, P. G. Hooper, J . C. Robb, Tram. Faraday Soc. 65 (1969)
1365.
[I31 Technical Data Sheets Ethyl Corporation (1958).
[ 141 T. ft. Jordan: Vapor Pressure of Organic Compounds, lnterscience Publisher?. New York 1954.
11.51 A. V. Grosse, J . M. Mavity, L Org. Chem. S (1940) 112.
[ 161 16 g Al powder, suspended in 500 m L n-heptane, was treated for 4 d
with C :Hr ( I bar) after addition of 30 g AICI, with stirring at 100°C. T h e
mixture was filtered and the filtrate freed of solvent (maximum 50°C.
10- mbar). The oily residue (17.75 g) was treated with pentane. A colorless powder precipitated out (24.14°/0 Al, 63.32% CI, 12.32% ethane;
deuterolysis: 95% [ I,l-DZ]ethane, 5% [DJethane). The structure of 2
shown here is in accord with the ‘ H - N M R spectrum (230K)
(rC(C‘-H)= - l.20,S(CH3)=0.92) as wellas with the ”C-NMRspectrum
(210 K) (6(C-H= 1.95 (d), 6(CHi)=5.71 (9)). The solid residue from the
filtered reaction mixture contains undissolved 1 in addition to excess Al
powder.
Me3C
y
e
I
Ni(cod)2
I?
2, R
I
-TI
SiMe,
100%
yield
Nickel-Catalyzed Cyclodimerization of
2-?err-Butyl- and 2-Trirnethylsilyl-1,3-butadiene**
Me,Si
[‘I
[**I
Max-Planck-lnstitut fur Kohlenforschung
Kaiser-Wilhelm-Platz 1, D-4330 Mulheim a. d. Ruhr I (FRG)
Max-Planck-Society fellowship
Address: Forschungsgruppe fur Petrolchemie der Ungarischen
Akademie der Wissenschaften
H-8200 Veszprem, Schonherr Z.u.8 (Hungary)
Control of metal-catalyzed reactions, Part 15.-Part 14: T. Bartik, P.
Heimbech, T. Himmler, J . Organomet. Chem. 276 (1984) 399.
Angeu,. Chrm l n t .
Ed. Engl. 24 il9SSi No. 4
+ b
4a
4b
60
18
7-0
Q-
Me3Si
7
0
i
By Tamas Bartik, Paul Heimbach,* Thomas Hirnmler,
and Richard Mynott
Dedicated to Professor Giinther Wilke on the occasion
of his 60th birthday
[*I Prof. P. Heimbach, Dr. T. Bartik [+I, Dr. R. Mynott,
Dipl.-Chem. T. Hirnrnler
.--we
SiMe,
SiMe,
=
10
Me3Si
toluene
A.4-
3b
3a
90
/2,
1).
y
o
yield
I
The oligomerization of 1,3-butadiene, first carried out
by H W . B. Reed on Reppe catalysts (L,Ni(CO),),[’I only
became a widely applicable synthetic method with the introduction of carbonyl-free Ni’ catalysts by G. Wilke et
al.”] Butadiene is cyclotrimerized on “naked” nickel ; in
the presence of P ligands (phosphanes or phosphites), cyclodimerization takes place to give divinylcyclobutane, 4vinylcyclohexene, and (2,Z)1 , 5 - ~ y c l o o c t a d i e n eIn
. ~ order
~~
to use the Ni”-catalyzed oligomerizations and co-oligomerizations better, the controlling factors, e.g., the conformation of the diene or the relative donor-acceptor behavior of
the substituents (structural and electronic variables, “molecular order effectors”)[41must be understood. We show
here how the substituents CMe, and SiMe3 in the 2-position of I ,3-butadiene affect reactivity and selectivity in the
Ni-catalyzed cyclodimerization.
Whereas the 2-alkyl-substituted 1,3-dienes that have
been studied to date oligomerize more slowly than butadiene,l5l 2-tert-butyl- and 2-trimethylsilyl-1,3-butadiene,1
and 2, respectively, surprisingly react appreciably faster.
Under conditionsi6I that result in 30-40% cyclotrimerization of butadiene on the ligand-free nickel catalyst, the
reaction of the dienes 1 and 2 is quantitative. In the case
of both dienes, cyclodimerization occurs and only substituted vinylcyclohexenes are formed (Scheme 1).
The isomeric pairs 3a/3b as well as 4a/4b and 4c/4d
each differ only in the respective substitution of the double bond in the ring. It was not possible to assign the structures unequivocally from simple ‘H- and I3C-NMR spectra. This was only achieved with the 2D-INADEQUATE
technique, in which the 1J(’3C-13C)
couplings are used to
generate a carbon-carbon connectivity map‘’’ (see Table
Me3C
SiMe,
SiMe,
4c
4d
20
2
Scheme I
Table 1. ”C-NMR data for 3a, 3b, and 4a-4d. The signal assignments for
3a, 3b [IZ], 4a, and 4c were made unequivocally on the basis of the 2D-INADEQUATE ”C-NMR spectra. &Values recorded relative to CDCI, and recalculated relative t o TMS [6(CDCI,)=77.0] [a]. For numbering of the C
atoms see Scheme 1.
~~
C
~~
3a
3b
4a
4b
4c
4d
145.0 (s)
118.1 (d)
35.5 (t)
35.9 (d)
32.5 (t)
26.0 (t)
164.3 (s)
105.1 (t)
29.31
28.9
36.9/
35.2
116.7 (d)
146.4 (s)
34.4 (1)
36.5 (d)
31.5 ( 1 )
26.8 (1)
164.6 (s)
105.1 (t)
29.0/
28.8
36.9/
35.2
138.2 (s)
135.5 (d)
34. I (t)
38.9 (d)
29.5 (t)
27.7 (t)
157.5 (s)
122.5 (t)
-0.9/
-2.1
135.0 (d)
138.7 (s)
33.9 (t)
39.3 (d)
28.8 (t)
21.8 (t)
157.6 (s)
122.4 (t)
- 1.01
- 2.2
138.3 ( 5 )
133.8 (d)
30.3 ( t j
29.6 (sj
26.7 (t)
22.8 ( t )
142.5 (d)
135.4 (d)
136.8 (sj
29.6 i t )
30.0 (s)
26.1 (t)
23.2 ( t )
142.4 (d)
110.9 (t)
- 2.41
- 4.7
110.9 (t)
-2.21
-4.7
la] The “C-NMR spectra were recorded in 10-mm tubes i n CDCI, at 75.5
M H r on a Bruker WM-300 NMR spectrometer. Typical measurement conditions for the 2D-INADEQUATE spectra: data matrix 2 K x 2 5 6 ( 1 , , / , ) , 128
scans per t7 increment: spectral width 11.9 kHz, 7-increment 5 ms (corresponding to average coupling ‘Jrc=50 Hz); cycle time 4.1 s.
The effect of the diene substituents (CMe,, %Me7, and
also CH3I8’) on the relative proportions of head (H) and
tail (T) coupling in the “diene” and “ene” parts for the
reaction giving Diels-Alder products is shown in Table 2.
The proportion of “symmetrically” coupled products
(HH +TT) increases in the series CMe, < SiMe3< CH,.
The rate of the Ni-catalyzed oligomerization is strongly
affected by the addition of triphenylphosphane: the reaction of butadiene is accelerated, that of 1 and 2 inhibited
(Fig. 1).
Using discontinuous inverse titration,[’] we were able to
show that the Ni-catalyzed cyclodimerization of diene 2 to
Diels-Alder products was practically fully suppressed
upon addition of triphenylphosphane in the range
- 1 <Ig[LJ,/[Ni], <0, whereas, for the diene 1 , for ligand
concentrations in the range - 1 <Ig[L],/[Ni], < 1, 3b replaces 3a as the main product in a very strongly inhibited
0 VCH Verlagsge.ye2lschaft mhH, 0-6940 Weinheim, I985
+
0570-0833/8Si0404-0313 9 02.50/0
3 13
Table 2. Proportions (“A)of the four possible couplings to Diels-Alder products for the 1,3-dienes 1 and 2 and for ?-methylbutadiene [8].
Diiners
R = CMe,
SiMe,
CH,
phenylphosphane (Ig[L],/[Ni], > 0); comparison of the
thermal with the catalytic dimerization shows that, catalytically, three isomers are formed: 4a and 4b in appreciably
larger proportion than in the thermal dimerization, and 4c
in only slightly increased proportion. The isomer 4d, on
the other hand, is only formed thermally.
Received: September I , 1984:
revised: November 2, 1984 [Z 988 IE]
Publication delayed at authors’ request
German version: Angew. Chem. 97 (1985) 345
R
10
’TT &
33
R
H6
”
H
I8
[I] H. W. 6. Reed, J . Clrem. Soc. 1954. 1931.
[2] a) H. Breil, P. Heimbach, M . Kroner, H. Muller, G. Wilke, Makromol.
Cbenr. 69 (1963) 18; b) G. Wilke, J. Organornet. Chem. 200 (1980) 349.
[3] W. Brenner, P. Heimbach, H. Hey, E. W. Miiller, G. Wilke, Jusfur Liebigs Ann. Chenr. 727(1969) 161.
/
0
20
27
2
0
R
.Turn\ (41 rhe proportions of the diferent coupling partners
h e part [a]
Diene p a n [b]
HH+?T[c]
H T + T H [dl
H
T
H
T
H
T
0
90
100
10
22
80
78
20
27
67
73
33
38
62
10
90
60
40
[a] Proportion of the dimers in which the ene was incorporated as head or
tail. [b] Proportion of the dimers in which the head or tail of the diene was
coupled with the terminal C atom of the ene components. [c] Sum of the HHand TT-coupled dimers. [d] Sum of the HT- and TH-coupled dimers.
reaction (yield < 15% for Ig[L],/[Ni],> +0.5). Nevertheless, this very retarded reaction is also clearly catalytic,
since the diene 1 thermally dimerizes to only 0.2% under
these reaction conditions in the absence of catalyst. For
diene 2, the slower uncatalyzed Diels-Alder reaction (yield
ca. 20%), in which the isomers 4a-4d are formed, is observed after “turning o f f ’ the catalysis by addition of tri-
[4] T. Bartik, R. Boese, P. Heimbach, H:G. Preis: 7’he concept of molecular
order effecrorr in orgunrc sjwhesis. Springer, Berlin, in press.
[ 5 ] P. W. Jolly in G. Wilkinson, F. G. A. Stone, E. W. Abel: Comprebensioe
Organomerallic Chembtry. Yo/. 8. Pergamon, Oxford 1982, p. 673.
[6] The series of experiments was carried out with a parent solution of
bis(cyclooctadiene)nickel(o) in diene/tolueoe; n-heaane served in the
GC analysis as internal standard for diene and catalyst. Triphenylphosphane was added in a benzene solution. After 6 h at 60‘C in sealed glass
ampules, the reaction mixtures were directly analyzed by gas chromatography (Perkin Elmer F20, 45m OVlOl glass capillary column). The concentration of catalyst was 16 mmol/L, the ratio nickel :diene 1 : 160. All
operations were carried out under argon. 1 was synthesized according to
[lo]; 2 by adaption of the procedure for 2-triethylsilyl-I,3-butadiene
[ I 11.
[7] A. Bax, R. Freeman, T. A. Frenkiel, M. H. Levitt, J . M a g n . Recon. 43
(1981) 478: review: R. Benn, H. Giinther, Angew. Chem. 95 (1983) 381;
Angew. Chem. Inr. Ed. Engl. 22 (1983) 390.
[8] H. Krische, Dissertation, Universitat Essen 1980.
191 a) F. Brille, P. Heimbach, J. Kluth, H. Schenkluhn, Angew. Chem. 91
(1979) 428; Angew. Chem. Int. Ed. Engl. 1X (1979) 400: b) C. A. Tolman.
J. W. Faller in L. H. Pignolet: Homugeneuus Catalwiisis with Metal Ph0.sphine Conrplere.s. Plenum, New York 1983, p. 69ff.
[lo] A. A. Korotkov, L. F. Roguleva. Zh. Org. Khim. I (1965) 1180.
[ I I ] M. Petrzilka. J. I. Grayson, S.vnthesic 1981. 753.
112) Since the differences between the ”C chemical shifts of 3a and 3b are
unexpectedly small, we recorded the ?D-INADEQUATE spectrum of
3b as a control. Especially noticeable are the similarities of the shifts of
C-3 and C-6, respectively, in 3a and 3b. The signals of 4b and 4d were
assigned by comparison with the other compounds.
Novel Trimerization of Cyctopentadiene with
a Homogeneous, Bifunctional
Palladium-Acid Catalyst System**
By Arno Behr and Wilhelm Keirn”
Dedicated to Professor Giinther Wilke on the occasion
of his 60th birthdaj>
Although bifunctional catalysts have found wide application in heterogeneous catalysis,[’] there are still only very
few corresponding examples of their use in homogeneous
catalysis.”’ Herein, we describe the synthesis of two hitherto unknown cyclopentadiene trimers using a novel, bifunctional, mixed catalyst comprising a palladium complex and a carboxylic acid (“Pd/H@”).
This preparative result indicates that bifunctional G%lytic systems can also play an important part in homogeneous catalysis with transition-metals.
In the trimerization of cyclopentadiene two isomers are
formed that can be preparatively separatedl3I and fully
trrninl
-
Fig. I.Opposite effect 01 the dddilioii ol~tiiphenylphosphaneo n the reaction
rate (yield curves) in the Ni-catalyzed oligomerization of butadiene (activation) and 2-[err-butyl- 1.3-butadiene 1 (inhibition); L : Ni = 10: 1 .
3 14
0 I‘CH Verlag~gesellsrliafrmbH. 0.6940 Wernheim. 1985
[*] Prof. Dr. W. Keim, Dr. A. Behr
lnstitut fur Technische Chernie und Petrolchemie
der Technischen Hochschule
Worringer Weg I, D-5100 Aachen (FRG)
[**I We thank F. Nii/ and R . Decorzant. Firmenich SA (Geneva). for their
help with the analytical-spectroscopic work.
0570-0833/85/0404-0314 $ 02.50/0
Angeu,. Clrem. I n t . Ed. Engl. 24 11985) No. 4
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nickell, trimethylsilyl, butyl, cyclodimerization, tert, butadiene, catalyzed
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