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Catalysed Synthesis of cis-1 2-Divinylcyclobutane.

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DSS[**] = 0).The mass spectrum shows the characteristic
main peak of tertiary aporphines (M - CHZ=N-CH~)at
mie = 256[91. The hydrochloride of (5) (C16H15N04-HC1,
m.p. 280 "C) was identified similarly. Furthermore, Nformylation, methylation, and subsequent reduction of the
formyl group yielded the naturally abundant alkaloid glaucine
(9). Thus the compound (S), which may be obtained in three
steps from papaverine ( 8 ) , provides the simplest route to
glaucine yet discovered.
Received: June 5th, 1967
[Z 524 IEI
German version: Angew. Chern. 79. 815 (1967)
by butadiene (not taken into account in the formulae given
here) and that the synthesis of (2) is thus transformed into a
synthesis of ( I ) . The product ( I ) is probably formed from
the bis-o-ally1 form (4).
i
- LgNi
- LgNi
- LgNi
[*] Prof. Dr. B. Franck and Dipl.-Chem. L.-F. Tietze
Institut fur Organische Chemie der Universitat
Neue Universitat
23 Kiel (Germany)
[l] Part 8 of Alkaloid Syntheses via Routes Similar to Biogenetic
Pathways by Oxidative Condensation. - Part 7: 171.
[2] R. Robinson: The Structural Relations of Natural Products.
Clarendon Press, Oxford 1955; E. E. van Tamelen, Fortschr.
Chem. org. Naturstoffe (Wien) 19, 242 (1961).
[3] C. Schopf and K. Thierfelder, Liebigs Ann. Chem. 497, 22
(1932).
[4] R. Robinson and S . Sugasawa, J. chem. SOC.(London) 1932,
789.
[5] J . Harley-Mason, J. chem. SOC.(London) 1953, 1465.
[6] B. Franck and G. Schlingloff, Liebigs Ann. Chem. 659, 123
(1962); B. Franck, G.Blaschke, and G. Schlinghoff,Angew. Chem.
75, 957 (1963); Angew. Chem. internat. Edit. 3 , 192 (1964).
[7] B. Franck and G . Blaschke, Liebigs Ann. Chem. 695, 144
(1966).
I81 S.M . Albonico, A. M . Kuck, and V. Deuiofeu, Liebigs Ann.
Chem. 685,200 (1965); A . H . Jackson and J . A. Martin, J . chem.
SOC.(London) I966, 2061.
[* *J DSS signilies sodium 2,2-dimethyl-2-silapentane-5-sulfonate.
[9] M . Ohashi, J . M . Wilson, I$. Budzikiewicz, M . Shamma, W .
A . Slusarchyk, and C. Djerassi, J. Amer. chem. SOC.85, 2807
(1963).
Catalysed Synthesis of cis-1,2-Divinylcyclobutane
By P. Heimbach[**I and W. Brenner[*I
cis-l,2-Divinylcyclobutane( I ) was first prepared by VogeZIll,
using a many-stage synthesis. Vogel's description of the Cope
rearrangement of this four-membered ring system to cis,cis1,5-cyclooctadiene (COD) (2) supported his hypothesis that
thermal formation of (2) from butadienegz] proceeds by
way of (I). The cis-compound ( I ) is also formed (8-17 %) in
admixture with, infer aZia, trans-divinylcyclobutane in the
photosensitized dimerization of butadiene [31. Butadiene can
by cyclodimerized faster in the presence of complexes of
zerovalent nickel that contain e.g.tris-(2-biphenylyl) phosphite
as ligand (Ni: P = 1:l), the rate being ca. 1 kg per g of nickel
in the catalyst per h at atmospheric pressure and 80 "C, and
the reaction yielding (2) (97%) and, by a side reaction, 4vinylcyclohexene (3) (2.7%) [41.
If the reaction is carried out in liquid butadiene to incomplete
conversion of butadiene, yields of up to 40 % of ( I ) , together
with (2) and (3), are obtained. The table shows the dependence of the yields on conversion of butadiene (catalyst:
Nio(C0D)Z 151 f tris-(2-biphenyl) phosphite, molar ratio 1 :1).
Conversion of butadiene (20 "C)
[ I ) , yield
We presume that, with high concentrations of butadiene, the
coordination positions o n nickel that become free on conversion of x-ally1 groups into a-ally1 groups become occupied
800
The rate of synthesis of ( I ) depends markedly o n the nature
of the ligand. With short reaction times (e.g. 0.5 h), yields
exceeding 30 % of ( I ) can be achieved even at 80 "C, although
thermal rearrangement of ( I ) to (2) has then already begun 161.
Pure (1) is obtained by distillation under vacuum: b.p. 8 "C/9
mm, ng = 1.4562[11. Substituted butadienes can also be
converted catalytically into cyclobutanes in good yields 171.
(Z 543a IE]
Received: March ZIst, 1967
German version: Angew. Chem. 79, 813 (1967)
Publication delayed at the authors' request.
[*I Dr. P. Heimbach and Dip1.-Chem. W. Brenner
Max-Planck-Institut fur Kohlenforschung
Kaiser-Wilhelm-PIatz
433 Miilheim (Germany)
[**I Paper read by P. Heimbach at Sheffield (Symposium on
AIlyIic and Olefinic Complexes of Metals) on April 11th. 1967.
111 E. Vogel, Liebigs Ann. Chem. 615, 1 (1958).
[2) K. ZiegZer and H. Wilms, Liebigs Ann. Chem. 567, 1 (1950).
[3] G. S.Hammond, N. J . Turro, and A . Fischer, J. Amer. chem.
SOC.83,4674 (1961).
[41 G. Wifke and P. Heimbach, Angew. Chem. 75, 10 (1963).
pp. 17-18; Angew. Chem, internat. Edit. 3, 105 (1963), pp. 112
to 113.
[51 B. Bogdanovit, M. Kroner, and G . Wilke, Liebigs Ann. Chem.
699, 1 (1966).
[6] P. Heimbach and W . Brenner, Angew. Chem. 79, 814 (1967);
Angew. Chem. internat. Edit. 6,800 (1967).
[7] Note added in proof (July 27th, 1967): Further investigations
have shown that cyclooctadiene and cis-l,2-divinylcyclobutane
are probably formed via the bis-x-ally1 form.
Catalysed Cope Rearrangement of
cis-l,2-Divinylcyclobutane
By P . Heimbachl**] and W. Brenner[*l
The yield of cis-1,2-divinylcyclobutane obtained on catalysed
dimerization of butadiene depends markedly on the extent of
conversion[']. This suggested that the first product ( I ) was
further catalytically aItered. Our f i s t experiments showed
that predominately cis,cis-l,5-cyclooctadiene (Z), with little
4-vinylcyclohexene (3), is formed from ( I ) . The rate of the
catalysed rearrangement of ( I ) could be determined a t 24 "C
by following the volume contraction and the change of refractive index during the reaction, as well as by gas-chromatographic analysis. The concentration of catalyst in the solution
was 0.2 or 0.1 molar (Ni:ligand = 1 :1). The rate is directly
dependent on the Ni concentration and the nature of the
ligand up to ca. 97 % conversion of ( I ) .
Fig. 1 shows the rate of the catalysed (24 "C) and also of the
thermal (uncatalysed) rearrangement (80 "C) of ( I ) to (2).
Angew. Chem. internal. Edit.f Vol. 6 (I967) / No. 9
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