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cis trans-Tetracyclo[6.1.0.02 4

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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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