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Olefin Metathesis with Polymer-Bound Tungsten Complexes.

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If. M . R . Hofmann, Angew. Chem. 85, 877 (1973); Angew. Chcm. Int.
The reactions compiled in Table 1 were performed under
the following reaction conditions:
In the case of aliphatic aldehydes, the aldehyde (0.2mol)
and divinyl sulfone (0.1mol) are jointly added dropwise to
a hot stirred solution of thiazolium saltL2](0.02mol) and
sodium acetate (0.04mol) in ethanol (200ml); aromatic and
heterocyclic aldehydes can be immediately added to the reaction solution so that only the double bond component has
to be added dropwise. The mixture is stirred for 12 h under
reflux, poured into water, and then extracted with chloroform
to give the corresponding y-diketone which is purified by
distillation or crystallization.
Ed. Engl. 12, 819 (1973).
O n the effect of the silver counterion cf. H . M . R. Hofmann, G . F.
P . Kernaghan, G . Greenwood, J . Chem. SOC.BlY71, 2258.
Table 1. Examples of addition of aromatic, heterocyclic, and aliphatic aldehydes to divinyl sulfone (R' =CH2=CH-).
indicate a delocalization of the positive charge by the hyperconjugative effect of the C'C2 and C4Cs bonds.
Received: November 25, 1977 [Z 889 IE]
German version: Angew. Chem. 90, 129 (1978)
CAS Registry numbers:
( 1 ) , 1724-44-3; ( Z a ) , X = B r , 106-96-7; (Zb), X=CI, 1111-97-3; ( 3 a ) , 6540480-0; ( 3 b ) , 65404-81-1; ( 4 a ) , 65404-93-5; ( 4 b ) , 65404-94-6; cis-(Sa), 6540495-7; trans-(Sa), 65404-96-8; cis45 b ) , 65404-97-9; trans-(5 b ) , 654W-98-0;
( 6 a ) , 3721-60-6; /6b), 22940-29-0; ( 7 b ) , 65404-99-1; ( 8 ) , 60690-49-5; cyclopentadiene, 542-92-7
( 6 a ) : N . A . LeBel, R . N . Liesemer, J. Am. Chem. SOC.87, 4301 (1965);
A . E. Hil1,G. Greenwood, H . M . R . Hoffmann,ibid.95,1338(1973).-(6b):
N . J . Turro, S . S . Edelson, J . R. Williams, T R . Darling, W B. Hammond,
J. Am. Chem. SOC.91, 2283 (1969); H . M . R . Hofmann, K . E . Clemens,
R . H . Smithers, ibid. 94, 3940 (1972).
W R. Moore, W R. Moser, J . E. La Prade, J. Org. Chem. 28, 2200
(1963); C. W Jefford, J . Mareda, J.-C. E . Gehret, nT Kabengele, W
D. Graham, U . Burger, J. Am. Chem. SOC.98, 2585 (1976).
R . C . Bingham, M . J . S . Dewar, D. H . Lo, J. Am. Chem. SOC.97, 1285
(1975).
H . Fackler, P . u. R . Schleyer, H . Mayr, unpublished results.
A New Preparation of Symmetrical y-Diketones"]
By Hermann Stetter and Hans-Jurgen Bender ['I
The thiazolium salt-catalyzed addition of aliphatic, aromatic, and heterocyclic aldehydesr2] to activated double bonds
can also be extended to a$-unsaturated sulfones.
Surprisingly, however, the product is not the expected y-keto
sulfone but a 1 : 1 mixture of y-diketone and y-disulfone. We
explain this result as a consequence of cleavage of the y-keto
sulfone (3) into sulfinate ( 4 ) and vinyl ketone ( 5 ) . A further
molecule of aldehyde ( I ) adds to the vinyl ketone to form
the symmetrical y-diketone (7), which is actually isolated.
The sulfinate ion reacts with unconsumed vinyl sulfone (2),
giving the y-disulfone (6) which can likewise be isolated.
R,-CHO
+
(I)
I
R,-CO-C
CH,=CH-SO,-R'
(2)
+Cat.
A
+
BH@~O,S-R'
I
RZ-CHO
+cat.
J.
R2-CO-CH,-CH,-CO-R2
R2
Yield
n-CsH7
n-C4H9
n-CzH11
n - C d 13
n-GH I 5
2-Fury1
2-Thienyl
Phenyl
R~-so,-cH,-cH,-so,-R~
+
R,-C 0-c H,-CH,-C
O-R,
["/.I [a]
B.p. rC/torr]
M.p. ["C]
Ref.
(m.p., b.p.1
43
56
53
63
61
75
48
46
11017
7510.3
9810.3
68
76
131
13&131
143-144
[3]: 53.5/0.1
[4]: 53
IS]: 100/0.4
161: 68.5
[7]: 131
[8]: 131-132
[9]: 144
__-
[a] Since no intermediates were isolated the yields are based upon the
amount of diketone ( 7 ) , i.e. calculated over all three reaction steps.
Received: November 25, 1977 [Z 890 JE]
German version: Angew. Chem. 90, 130 (1978)
CAS Registry numbers:
(I )(R2=n-C3H7),123-72-8;( 1 ) (R2=n-C4H9), 110-62-3;( 1 ) (R2=n-CsHl I),
66-25-1 ;(I)(R2 = n-C6H13),111-71-7;( I ) (R2 = n-C7H15),124-13-0;( I J (R2=
2-furyl), 98-01-1; ( I ) (R2=2-thienyl), 98-03-3; ( I ) (R2=phenyl), 100-52-7;
39690-70-5; ( 7 )
(2) (R' =CHZ=CH-),
77-77-0; (6) (R' =CHz=CH-),
(R2=n-C3H7),22633-21-2;( 7 ) (R2= n-C4H9),15982-65-7;( 7 ) (Rz =n-CsHl
22633-22-3; ( 7 ) (R2=n-C6H13),54277-01-9; ( 7 ) (R2=n-C7H1s),65378-70-3;
( 7 ) (R2=2-furyl), 22111-14-4; ( 7 ) (RZ=2-thienyl), 13669-05-1; ( 7 ) ( R 2 =
phenyl), 495-71-6
[I]
131
[4]
[5]
[6]
[7]
[S]
191
-B
-
2 R,-CHO
(4)
(5)
+
f
121
H,-CH,-SO,-R
(3)
R~-CO-CH=CH,
2 R'-SO,-CH=CH,
Addition of Aldehydes to Activated Double Bonds, Part 18.-Part 17:
H . Stetter, J . Nienhaus, Chem. Ber., in press.
H . Stetter, Angew. Chem. 88, 695 (1976); Angew. Chem. Int. Ed. Engl.
15, 639 (1976).
W B. Sudweeks, J. Org. Chem. 40, 1131 (1975).
S . Yashihiko, I . Hashimoto, M . Ryang, J. Org. Chem. 33, 2159 (1968).
G. Hooz, D. M . G u m , Chem. Commun. 1969, 139.
M . Larcheveque, G . Valette, 7: Cuuigny, Synthesis 1975, 256.
E. Niwa, Chem. Ber. 102, 1443 (1969).
D. C . Owsley, M . J . Nelke, J . J . Bloomfield, J. Org. Chem. 38, 901
(1 973).
M . Scheidt, L. Knorr, Ber. Dtsch. Chem. Ges. 27, 1168 (1894).
+ R1 -Sq-CH=CH,
J.
R'-SO,-CH,-CH,-SO,-R'
(7)
(6)
The reaction has been observed for several aryl vinyl sulfones
and can be exploited preparatively when divinyl sulfone
(R'=CH=CH2) is used as double bond component since
separation of y-disulfone and y-diketone is then a simple
operation. Moreover, the ratio of aldehyde to vinyl sulfone
can then be limited to 2: 1.
[*] Prof. Dr. H. Stetter, DipLChem. H.-J. Bender
Institut fur Organische Chemie der Technischen Hochschule
Professor-Pirlet-Strasse1, D-5100 Aachen (Germany)
Angew. Chem. Int. Ed. Engl. 17 ( 1 9 7 8 ) N o . 2
Olefin Metathesis with Polymer-Bound Tungsten
Complexes[']
By Siegfried Warwel and Peter Buschmeyed']
Ready separation of homogeneous transition metal catalysts
from the substrate and catalyst recycling processes are of
decisive importance in industrial applications. A possible solution of such problems is proved by the so-called heterogeniza-
p]
Priv.-Doz. Dr. S. Warwel, Dipl.-Chem. P. Buschmeyer
Jnstitut fiir Technische Chemie und Petrolchemie der Technischen Hochschule
Alte Maastrichter Strasse 2, D-5100 Aachen (Germany)
131
tion of transition metal complexes, i. e. their linkage to insoluble inorganic or organic carriers.
We now describe the first use of polymer-bound carbonyltungsten complexes for the metathesis of open-chain monoolefins. The tungsten-polymer complexes ( I ) and (2)
hexene, mixture of n-octene isomers) and confirmed; cometathesis of these olefins with vinylcyclohexene was also
possible. The development of further complex catalysts with
polymeric ligands could prove of value in elucidating the
mechanism of olefin metathesis.
Metathesis of trans-3-heptene with (2)/iBuAlC12/02
+ NaPPhi
I
- NaCl
prepared according to Pittman et al.[*]from a commercially
available Merr$eld resin[31 effect, after activation with
iBuAlCl2/02, selective metathesis of trans-3-heptene to give
an equilibrium mixture.
Compound (2) (60mg, containing 9.3 % W) is placed in
a dry ca. 10ml-capacity Schlenk tube. After repeated
evacuation and flushing with argon, trans-3-heptene (2.06 g,
21 mmol) containing 15 wt% of methylcyclohexane as G C
standard as well as isobutylaluminum dichloride (0.12mmol;
0.24ml of a 0.5 M solution in chlorobenzene) and O2
(1.4m1, 0.06mmol) are added from syringes; the contents
of the vessel are mixed with a magnetic stirrer. After 60min
a sample of the reaction solution is treated with small amount
of C H 3 0 H and analyzed by gas chromatography (3-heptene
67.0, 3-hexene 14.6, 4-octene 18.4 wt %). Compound (2) is
separated from the other compounds by filtration, washed
with ca. 20ml of CH30H, dried at 25 "C in uacuo, and re-used
for metathesis.
Received: November 15, 1977;
supplemented: December 15, 1977 [Z 891 I€]
German version: Angew. Chem. 90, 131 (1978)
Compound (1) or ( 2 ) was then separated from cocatalyst
and the olefins by filtration. After washing with methanol
and drying at 25°C in uucuo the complex catalysts could
be re-used.
The tungsten complex ( I ) coordinated to the polymeric
matrix proved to bea storage catalyst : the polymeric phosphane
ligand serves as reservoir for a coordinatively unsaturated
tungsten species which is displaced by the alkylaluminum
compound and then forms a homogeneous catalyst for the
metathesis reaction. Compound (1) can therefore be re-used
only in a limited number of runs (Figure 1).
CAS Registry numbers:
trans-3-heptene, 14686-14-7; 3-hexene, 592-47-2; 4-octene, 592-994; diethenylbenzene, polymer with ethenylbenzene, 9003-70-7; NaPPh2, 4376-01-6;
W(CO)6, 14040-11-0; Na[W(CO),(q-C5H5)], 12107-36-7; i-BuAICI,, 1888-875
[I]
Olefin Metathesis, Part 5. This work was supported by the Deutsche
F0rschungsgemeinschaft.-Part 4: S. Warwel, A. Aiuasidis, Chem.-Ztg.
101, 361 (1977).
[2] G. 0. Evans, C. U . Pirtman Jr., R . McMillan, R . 7: Beach, R . Jones,
J . Organomet. Chem. 67, 295 (1974); C. U . Pirtman Jr., R . F . Felis,
ibid. 72, 399 (1974).
[3] Chloromethylated polystyrene (Cl content: 5.1 "/.) crosslinked with 2 %
of divinylbenzene available from the Merck-Schuchardt company.
Quantitative Resolution of Enantiomers of trans-2,3Epoxybutane by Complexation Chromatography on an
Optically Active Nickel@) Complexp*]
Number of recyclings-
Fig. 1. Metathesis of trans-3-heptene with polymer-bound tungsten complex
catalysts-conversion as a function of the number of recyclings on use of
a) ( I )/iBuAIC12/02 and b) (2)/iBuAICI2/02 in the ratio W : Al: O2 : olefin
= 1 : 4 :2 : 700 (22-24°C;
60 min per metathesis reaction).
In contrast, the tungsten complex (2) covalently bonded
to the polymer combined the advantages of homogeneous
and heterogeneous metathesis catalysts, i. e. activity and selectivity under mild conditionson the one hand, and ready removal
from the reaction solution, regeneratability, and especially
the possibility of frequent re-use, on the other hand. O n
repeated recycling the activity profile of (2) corresponds to
that of heterogeneous catalysts; low initial activity (experiment 1) is followed by a maximum (experiments 2 and 3)
which then adjusts to a constant value (experiments 4 to 8).
The scope of the catalysts was examined with other openchain olefins having an internal double bond (cis- and trans132
By Volker Schurig and Waldemar Burkle"]
Enantiomers often differ characteristically in their pharmacological and physiological properties (substrate-receptor
interaction). It is therefore advantageous to be able to directly
determine the enantiomer composition of chiral substrates
rapidly and quantitatively, without having to resort to derivatization and measurement of optical rotation, and to gain
information about the kinetic and thermodynamic factors
of chiral differentiation.
The method of choice for this purpose is the gas chromatographic resolution of enantiomers on optically active stationary phases by selective interactions between hydrogen bonds,
as introduced by Gil-Av and Feibush"].
We recently reported the first chromatographic resolution
of a chiral olefin by enantiospecific n-complexation on a rhodium(1) compound (I)['] and thus showed that the rapid
and reversible ligand-metal coordination interaction can have
the necessary thermodynamic parameters for "chiral recognition" in G C systems.
['I
Univ.-Doz. Dr. V. Schurig, W. Biirkle
Institut fur Organische Chemie der Universitat
Auf der Morgenstelle 18, D-7400 Tiibingen (Germany)
[**I This work was supported by the Deutsche Forschungsgemeinschaft
and the Fonds der Chemischen Industrie.
Angew. Chem. lnt. Ed. Engl. 1 7 (1978) No. 2
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