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Cyclodimerization of Methylenecyclopropane on a Ni(0) Catalyst.

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Table 2. Decomposition constants for benzoylated oximes in aqueous solution at pH 8.1, determined by UV
= 280 nm).
spectroscopy (Lax
t I , 2 (min)
kx
lo4 (min-') [b]
pK. value of the oxime group
Reactivation (%) [c]
3
570
2310
t 20
7.68
49
700
99.0
7.78
60
7.81
62
860
1825
3600
80
38
15
8.01
7.83
74
17
8.34
0
[a] (19) = 4-(Hydroxyiminomethyl)-l-methylpyridiniumiodide
[b] The reaction is pseudo-first order.
[c] At an oxime concentration of 7.5 x
molfliter.
Since the rate of the decomposition (C) depends on the
kinetic methine acidity the half-reaction time t1,2 serves
as a measure for this (Table 2).
Rapid enzyme activation occurs only if the nucleophilicity
of the oximate anion and acidity of the methine proton
have minimum values.
Received: January 31,1972 [Z 595 IE]
German version : Angew. Chem. 84,354(1972)
[l]J . B. Wilson and S . Ginsburg, Biochim. Biopbys. Acta 18, 1681
(1955).
[2] A. Liittringhaus and I . Hagedorn, Arzneimittel-Forsch. 14,1(1964);
W D.Erdmann and H . Engelhard, ibid. 14,5 (1964).
[3] C.Fest and K.-J. Schmidt in R . Wegler: Chemie der Pflanzenschutzund Schadlingsbekampfungsmittel. Springer-Verlag, Heidelberg 1970,
pp. 363 and 411.
[4] I. Hagedorn, W H . Giindel, and K . Schoene, Arzneimittel-Forsch.
19, 603 (1969).
[5] H. P . Lorenz, Diploma thesis, Universitat Freiburg 1970.
[6] Prof. W D. Erdmann, of the Toxicological Institute of the University of Gottingen determined this value as the maximal attainable
enzyme activity (%) after addition of the reactivator to AChE completely blocked by diisopropyl fluorophosphate (DFP, 1 x
molfliter).
[7] The method of A. Albert and E. P . Serjeant (Ionization Constants
of Acids and Bases. Methuen, London 1962)was modified [ 8 ] .
[8] I . Stark, Dissertation, Universitat Freiburg 1971.
191 W Hohler, Diploma thesis, Universitat Freiburg (1969).
[lo] I. Stark, Diploma thesis, Universitat Freiburg (1968).
[11] The pK, value is derived from pK., =7.54 and pK,,=8.12.
The two oxime groups of the symmetrically structured compound
are identical in chemical behavior and the nucleophilicity of their
anions correspond to that of a monooxime with pK,=7.80.
[12] K . Schoene, Dissertation, Universitat Freiburg 1967.
A nickel catalyst freshly prepared in 1,5-~yclooctadiene[~~
or in methylenecyclopropane from 2,4-pentanedionatonickel and ethoxydiethyalane affords an oligomer mixture
of the same composition. However, in the presence of a
titanium catalyst prepared from 1 mmol of titanium
tetrachloride and 10 mmol of ~hlorodiethylalane[~~
highermolecular oligomers (C,H,), are formed almost exclusively
(>95%).
The dimers separated in pure form by preparative gas
chromatography were previously unknown. They could be
identified by their spectra as 5-methylenespiro [2.4]heptane
(2) and dispiro[2.1.2.l]octane ( 3 ) . [ ( 2 ) : mol. wt. (MS)
108. IR (neat): 1658 (v,,),
1010 cm-' (ZjA). 'H-NMR
(100 MHz, neat): .s=5.31 (2 H/m), 7.68 (2 H/t), 7.89
(2 H/m), 8.55 (2 H/t), and 9.68 ppm (4 H/s). - ( 3 ) : Mol. wt.
(MS) 108. IR (neat): 3090 (vCHA)
lo00 cm-' ( ~ 5 ~'H-NMR
).
(100 MHz, neat): ~ = 7 . 8 0(4 H/s) and 9.55 (8 H/s)].
Transition-metal catalyzed syntheses of four-membered
rings resembling the formation of (3) from ( I ) are
known for several dienes15-'I but have hitherto been
observed for monoalkenes in only one isolated case[81.
Presumably (2) and (3) are formed via the same unstable
organonickel intermediates ( 4 ) with x-Ni(C=C) bonds
Cyclodimerization of Methylenecyclopropane
on a Ni(0) Catalyst
By Paul Binged"
Methylenecyclopropane (1) ['* *I, which is now readily
available in good yield, is thermally stable up to ca. 150"C,
but can be oligomerized by bis(l,5-cyclooctadiene)nickel [Ni(COD),][31 at as low a temperature as - 15"C.
Irrespective of whether it is conducted without a solvent
or in pentane, benzene, or diethyl ether, the exothermic
reaction yields a mixture containing 45% of dimers
[65 % of (2) and 20% of ( 3 ) ] ,ca. 10% of trimers (6 isomers),
and about 45% of higher-molecular oligomers with a
mean cryoscopic molecular weight of 1100. In these
experiments ca. 1 mol of pure ( I ) was treated with 1 mgatom of Ni.
[*] Dr. P. Binger
Max-Planck-Institut fur Kohlenforschung
433 Mulheim/Ruhr, Kaiser-Wilhelm-Platz 1 (Germany)
Angew. Chem. internat. Edit. Yo!. I I (1972)
I No. 4
and (5) with o-NiC bonds. The ring of ( I ) should
not open immediately on complex formation with the
nickel['] but, as with the cyclopropylmethyl compounds of
several main-group elements (Li[''',
Mg" 'I, and
B"]), only during isomerization to the 3-butenyl group
[f5)
+
(611.
309
Methylenecyclopropane is known to form complexes with
nickel(0) using its C=C bond without ring opening[12!
Experimental:
Ni(COD), (0.25 g) is treated dropwise at - 15°C during 1 h
with ( 1 ) (40 g, 0.74 mol). The dark red solution is stirred
for a further 20 h and volatile constituents (23.2 g) are then
removed in a vacuum (0.001 torr, max. bath temp. 120°C).
There remains a dark viscous oil (15.7 g).-Fractionation
(spinning band column): 18.5 g (46%) of b. p. 58-62 oC/lOO
torr [GC: 19% of ( 3 ) and 67% of ( 2 ) , residue (14%)
containing 15 unknown compounds]; 0.35 g of b.p
7(&9OoC/100 torr [GC: 5.9% of ( 2 ) , 57.3% of 1,5-cyclooctadiene and 17.1% of C8HI0 (mol. wt. (MS) 106),
residue (19.8%) containing 16 unknown compounds] ;
and 3.8 g (9.5%) of b.p. 100-118"C/20 torr [GC/MS:
96% of C,,H,, ( 2 6 isomers; mol. wt. 162).--'H-NMR
spectrum of CsHIo (60 MHz, benzene): r=3.46 (rn),
4.00 (s), 4.8-5.18
(m) and 7.62 ppm (s) in the ratio
0.9 :1.1 : [4] :4; presumably 3-methylene-I-vinyl-I-cyclopentene, calc. 1:1 :[2 + 21 :4.
Received: November 22,1971 [Z 600IE]
German version: Angew. Chem. 84,352 (1972).
[l] R. Koster, S. Arora, and P. Binger, Synthesis 1971, 322.
[2] R. Kbster, S. Arora, and P. Binger, Angew. Chem. 81, 186 (1969);
Angew. Chem. internat. Edit. 8,205 (1969).
[3] 8. BogdanoaiC, M . Kroner, and G . Wilke, Liebigs Ann. Chem. 699,
l(1966).
[4] H . Breil, P. Heimbach, H. Muller, and G. Wilke, Makromol.
Chem. 69, 18 (1963).
[5] P. Heimbach and W Brenner, Angew. Chem. 79, 813 (1967);
Angew. Chem. internat. Edit. 6, 800 (1967).
[6] G . N . Schrauzer, Advan. Catal. 18,377 (1968).
[7] F . V Hoooer and R . V Lindsey jr.. J. Org. Chem. 34.3051 (1969).
[8] F . J . Weigert, R . L. Baird, and J . R. Shapley, J. Amer. Chem. SOC.
92,6630 (1970).
191 R. Noyori, 7: Odagi, and H . Takaya, J. Amer. Chem. SOC.92, 5780
(1970).
[lo] P. T Lansburg and V. A . Pattison, I. Amer. Chem. SOC.85, 1886
(1963).
[ll] J. D.Robertsand R. H.Mazur, J.Amer. Chem. SOC.73,2509 (1951).
[12J M . Engtert, P. W Jolly, and G. Wilke,Angew. Chem. 83,84(1971);
Angew. Chem. internat. Edit. 10, 77 (1971).
tions are possible for this system : the completely cis-form
(C3" symmetry) ("crown") ( I ) and the mirror-plane symmetrical trans-form (C,-symmetry) ("peaked cap") (2)
A bridged cis-trishomobenzene was recently obtained by
de Meijere, Kaufmann, and Schallner"' ; heteroanalogous
derivatives of ( I ) and (2) have been described by Prinzbach and St~sche[~].
We report here the preparation of the parent hydrocarbon
(2). Dimethyl tricyclo[5.1.0.02~4]octane-5,6-bicarboxylate
( 4 ) was obtained by cyclopropanation of dimethyl trans1,2-dihydrophthalate (3) ;hydrolysis of ( 4 ) and subsequent
electrolytic decarboxylation afforded a hydrocarbon previously described by Roth and PeltzerL5'and identified as
trans-tricyclo[5.1.0.0z~4]oct-5-ene ( 5) by its I
R and NMR
spectra.
The Cu(r)-catalyzedreaction of (5) with diazomethane led
to a product to which high-resolution mass spectroscopy
assigned the molecular mass 120.093772; for ( I ) and (2)
(i. e. for C,H,,) calculation gives 120.093896. The structure
and the "peaked cap" configuration with C, symmetry (2)
of the product are further proved by the 'H-NMR spectrum: for the completely cis-form ( I ) only three types of
proton are to be expected, but for (2) seven in the proportions Ha:Hb:H' :Hd :He:H' :Hg=2 :2 :2 :2 :2 :1:1.
The NMR spectrum (CCl,, 100 MHz) confirms configuration (2) : T = 10.1 (2Hb/q), 9.9 (H'/q) (width of the quartets each ca. 15 Hz), 9.50 and 9.58 (2 Ha+ Hg/m) (width of
the multiplets each ca. 20 Hz)"', 8.9-9.4 ppm (2H',
2Hd+2He/m)l6].
The assignment of the secondary protons makes use of the
known fact that the coupling constants between transprotons on the cyclopropane ring are smaller than those
between cis-protons"! All the assignments were further
strengthened by results of analysis of the NMR spectra of
trans- and cis-tricyclo[4.1.0.0Z~4]octane [(6) and (7)I by
Braun'".
cis,t rans-Tetracyclo[6.1 .O.O 2* .O 7]nonane,
"trans-Trishomobenzene"
By Martin Engelhard and Wolfgang Liittke"'
Our investigations of quasiconjugative interactions between three-membered rings have so far been devoted
mainly to bicyclopropylI'. 'I. Such effects should be more
clearly visible with compounds in which the cyclopropane
rings are fixed by cyclic bonding. Particular interest appeared to attach to the system, called occasionally trishomobenzene, that can be constructed formally by adding three
methylene groups to a benzene molecule. Two configura-
[*I DlpLChem. M. Engelhard and Prof. Dr. W. Liittke
Organisch-Chemisches Institut der Unlversitat
34 Gottingen, Windausweg 2 (Germany)
310
Received: January 21, 1972 [ Z 594IE1
German version: Angew. Chem. 84, 346 (1972)
[l] W Liittke, A. de Meijere, H. Wolfl,H . Ludwig, and H. W Schrotter,
Angew. Chem. 78, 141 (1966); Angew. Chem. internat. Edit. 5, 123
(1966).
[2] 0. Bastiansen and A. de Meijere, Acta Chem. Scand. 20, 516
(1966); cf. 3. Erakerand Chr. Rdmming, ibid. 21, 2721 (1967).
[3] A. de Meijere, D. Kaufmann, and 0. Schallner, Angew. Chem. 83,
404 (1971); Angew. Chem. internat. Edit. 10, 417 (1971).
141 H . Prinzbach and D. Stusche, Angew. Chem. 82, 836 (1970);
Angew. Chem. internat. Edit. 9,799 (1970).
[5] W R. Roth and B. Peltier, Liebigs Ann. Chem. 685, 56 (1965).
[6] A singlet at ~ = 8 . 7ppm is ascribed to an impurity.
[7] G . Schrumpf and W . Lutrke, Liebigs Ann. Chem. 730,100 (1969)
181 A. A . Bothner-By, Advan. Magn. Resonance I , 195 (1965).
[9] S. Braun, Dissertation, Universitat Gottingen 1970.
Angew. Chem. internat. Edit.1 Vol. 11 (1972)
I No. 4
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