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Convenient Synthesis of Vinylsilanes and Their Use in Ketone Synthesis.

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Table 1. Condensation reactions between p-toluenesulfonates (R-OTos) and
Grignard compounds ( R ' - M u ) .
-
R in
R-OTos
R' in
R'-MgBr
[d]
R-R'
Yield
[b]
[%I
[c]
19
98
90
98
96
0
51
0
3
99
[a] OTs= OS01-ChH4-CH3.
[b] Grignard reagent always added in excess (1.4 equiv.).
[c] Glc analyses. internal reference substance: calibration factors for peak
area correction: standard deviation f 3 %.
[d] I 1 ), X = OTos.
MgBr
YO C C+L,v--v-A
H,
0
[8] Identity and purity were checked by elemental analyscs, vpc, as well
and "C-NMR and infrared spectra.
as mass, 'H-,
[9] Corrected for an impurity of 5'la cis isomer present in the starting
material.
[lo] Formation of this normal acetate reaction product may be even further
reduced (<5"/0) if larger amounts of CuI ((.a. I equiv.) are used instead
of LlzCUCI,.
[ill Note added in proof: Lithium dialkylcuprates can also undergo condensation reactions with tertiary allylacetates; however, they overwhelmingly
involve attack at the vinylogous position and allylic shift of the double bond
(P.Rona, L. Tdkes, J . Tremble, and P . Crabbh, Chem. Commun. 1969. 43;
R. J . Anderson, C . A . Henrik, and J . B. Siddall, J. Amer. Chem. SOC 92, 735
(1970)).
Convenient Synthesis of Vinylsilanes and Their Use
in Ketone Synthesis[**]
By Bengt-Thomas Grobvl and Dieter Seebach[']
Vinylsilanes ( I ) can be converted into carbonyl derivatives
( 3 ) via epoxides (2)[11. Thus all C-C coupling reactions
in which vinylsilanes are formed represent potential methods
for producing carbonyl compounds.
(8)
Similarly, cis-2-octene (50%)was obtained from cis-crotyl acetate.
2,2-Dimrthyldecane:
Octyl p-toluenesulfonate (40 mmol) in tetrahydrofuran solution (50 ml) was treated at - 78' C with tert-butylmagnesium
bromide (56mmol in 32ml of diethyl ether) and LiZCuC14[']
The reaction mixture
(0.2 mmol in 2 ml of tetrahydrof~ran)[~].
was allowed to warm to room temperature during 2 h and
stirring was continued for other 12h. An aliquot sample was
withdrawn and, after decane had been added as an internal
standard, subjected to glc analysis. The main part of the
reaction mixture was acidified with 2 N sulfuric acid, washed
twice with water (2 x 50ml), dried (CaS04), and evaporated.
Distillation and rectification (b. p. 77-78 C/15 torr) yielded
5.1 g (75%) of pure 2,2-dimethylde~ane[~].
trans-2-Octene :
In the same manner trans-~rotylacetate[~~
( 100mmol), n-butylmagnesium bromide (140 mmol), and Li2CuCI4 (0.2 mmol)
were mixed in a total volume of 50ml of tetrahydrofuran
and 40ml of diethyl ether. A 62% yield of trans-2-0ctene[*.~I
(b. p. 120-122°C) was isolated by spinning band column
distillation ; in addition 9% of 5-methyl-5-nonanol (b.p. 78 to
80 C/2 torr) was obtained. According to glc (6 m 15 Yosilicone
rubber SE-30, 100'C; 2 m 5%+25Y0 AgN03+diethylene
glycol, 30 "C) the yields amounted to 88 % and 11%, respectively[''].
Received: September 10,1973 [Z 947 I€}
German version: Angew. Chem. 86, 50 (1974)
[ I ] M . Tamiira and J . Kochi, Synthesis 1971, 303; see also H. Gilman, R.
G. Jonus, and L. A. Woods, J. Org. Chem. 17, 1630 (1952).
[2] M . Schlossvr and G. Fotryrrut, Synthesis 1972, 200: Chem. Ber., in press.
[3] The catalytically active species appears to be a copper(1) derivative:
Cut is as effective as Li,CuCI;
[4] H. Giiman, R. G. Jones, and L. A . Woods, J. Org. Chem. 17, 1630 (1952);
H. 0. House, W L. Respess, and G. M . Whitesides, ibid. 31, 3128 (1966);
G. Wittig and G . Klar, Liebigs Ann. Chem. 704, 91 (1967); E . J . Corey and
G . H . Posner, J. Amer. Chem. Soc. 89,3911 (1967); 90,5615 (1968);G. H. Posner
and C . E. Whitten, Tetrahedron Lett. 1973, 1815.
[5] Reviews: J . F. Normont, Synthesis 1972, 63: see also: W Tochrrrmann,
Angew. Chem. 78, 355 (1966). Angew. Chem. internat. Edit. 5 , 351 (1966):
G. W t i g , Quart. Rev. t h e m . SOC.20, 191 (1966): G . H. Posnvr, Org. React.
19, I (1972).
[6] Review: M . Schlosscrr Struktur und Reaktivitat polarer Organornctalle.
Springer-Verlag, Heidelberg 1973, particularly pp. I 1-16.
[7] Subsequent addition of thc p-toluenesulfonate, t2.y. after 3 h at 0 C ,
leads to thc same result.
Angew. Chem. internat. Edit. 1 Vol. 13 (1974)
1 No.
1
We now describe new 2-silyllithium reagents (8) and ( 9 )
from which vinylsilanes (10)--( 22) having different substitution patterns are accessible by simple C-C bond formation
or by Peterson olefination.
\I
-Si\
(3Si)2 CHz
C=C Hz
Br/ (6)
I
f 71
1
r<Li
i
Compound (8)r2J is produced from tris(trimethylsily1)methyllithium (4)c3I which is first converted into the olefin (5)14]
in 70% yield by a Peterson reactionC5! Compound ( 5 ) can
be transformed into (6)[61,which is subjected to bromine-lithium exchange with tert-b~tyllithium[~~.
The substituted reagents of type (9a) are prepared in more than 900/;, yield
byaddition[2a.81ofalkyllithium compounds R'Li to ( 5 ) . Solutions of reagent (9b)c3"] are also obtained in yields exceeding
90YOby metalation of (7) in an improved process.
Compound (8) was subjected to the action of alkyl halide,
aldehyde, or ketones, whereupon the products ( l o ) were
[*] DipLChem. B.-Th. Grobel and Prof. Dr. D. Seebach
Fachbereich 14 Chemie, Institut fur Organische Chemie der Universitdt
63 Giessen, Ludwigstrasse 21 (Germany)
[**I This work was supported by the Fonds der Chemischen Industrie:
B.-Th. G. wishes to thank the Studienstlftung des Deutschen Volkes for
a grant.
83
Table 1. Substitution patterns, yields, and a number of characteristic NMR data for the products (101, ( l l ) , and (12). In all reactions the electrophile
was added t o a T H F solution of the lithium reagent at -80°C and the reaction mixture allowed to warm over 14h. All the compounds gave correct
elemental analyses.
Reaction
Electrophile
n-CSHiI
C6H5CH(OH)
(CH2)5C(OH)
(CsH5)2C(OH)
formaldehyde
benzaldehyde
formaldehyde
formaldehyde
benzaldehyde
cinnamaldehyde
nGH9
n-C4H9
F-C~H~
KzH9
t-CaHr
t-CbHu
R"
benzdidehyde
cinnamaldehyde
benzophenone
~~
to'.] 1.3
n-pentyl iodide
benzaldehyde
cyclohexanone
benzophenone
(Yb)-il2)
~
Yield
C6H5
CH=CHChH5
C6H5
olefinic H
0.05
83
64
60
62
H
ChHs
H
H
ChH5
C H=CHC6H5
NMR [6]
s1lyl
5.28,
5.40,
5.29,
5.03,
-0.08
0.12
0
0.05
73
62
64
71
64
- 0.08, 0.15
60
0.13, 0.25
5.50
5.68
5.56
5.53
5.28, 5.50
6.78, 7.2 [b]
5.30, 5.44
5.46, 5.57
6.92, 7.18 [b]
6.24-7.25 [b]
-0.0x,0.15
0 08
0.09
R4
__________~____
H
H
ChH5
70
35
65
[.I
5.79, 6.37, 6.X5. 7.27 [b]
5.6-6.0, 6.4-7.0 [b]
6.19
0.03. 0.17
0.1 5. 0.25
-0.12
~~
[a] Based on distilled products.
[b] As seen from the NMR spectra, E / Z isomeric olefins are formed, ratio 1 :1.0-1:1.4
[c] nAO= 1.5230 ( L . H . Summer et a / . ,J. Amer. Chem. SOC.76, 1613 (1954): 1.5270).
formed in &85 % yield (see Table 1). Reaction of reagents
( 9 ) with nonenolizable carbonyl compounds proceeds via
olefination to give good yields of the vinylsilanes ( I I ) and
( 12) (see Table
As the first example of the production of a ketone from
a vinylsilane we may cite the epoxidation of (1 1 ), R' = turtbutyl, R2= H, to (13) and its hydrolysis to methyl neopentyl
therein; C. Trindle, J.-Z Hwang, and F . A . Care)', J. Org. Chem. 38. 2664
(1973); F. A . Curcy and 0. Hrrnandrz, rhrd. 38, 2670 (1973).
[6] G. Fritz and J . Grobe, 2. Anorg. Allg. Chem. 309, 99 (1961).
[7] H. Nrumann, Diplomarbeit, Universitit Giessen 1973.
183 Addition of RLi lo monosilylolefins. e.y.: L. F. Cason and H . G. Brooks,
J . Amer. Chem. SOC. 74, 4582 (1952); J. Org. Chem. 19, 1278 (1954). 7:
H . Chan, E. Chuny, and E . Vinokur, Tetrahedron Lett. 1970, 1137.
[9] Dinitrophenylhydrazone m.p. 99.3-100 C [ F . C. Whitmorr r r a/.. J.
Amer. Chem. SOC.63,2035 (1941): m.p. IOO'C].
Dimethylarsenido-Transition Metal ComplexesStable Organometallic Lewis Bases
By Wolfgang Mulisch and Max Kuhn"]
ketone {24)191 in an overall yield of 74%. The origin of
the individual C atoms of (14)is indicated below the formula.
We thus have at our disposal a novel building-block system
for the synthesis of ketones.
Received: October 29, 1973 [Z 941 I€]
German version: Angew. Chem. 86.102 11971)
[***I Nore added in proof: Meanwhile H. Sakuroi er 01 (Tetrahedron Lelt.
1973, 4193) have published another route for preparation of i Y b ) giving two
examples of its reaction with ketones.
[ I ] Only aldehydes have so far been synthesized by this route: G . Stork
and E. Coh:in, J. Amer. Chem. SOC.Y3, 2080 (1971).
121 (8). Mg instead of Li: see a) A. G. Brook, J. M.DifJ and D. G. Anderson,
Can. J. Chem. 48. 561 (1970): (81, (C2H5),Si instead of (CH3),Si and Mg
instead of Li: see b) G. Stork and B. Gunem, J. Amer. Chem. SOC.95. 6152
(1973); (S), (C6HJ)3Si instead of (CH&Si: see [2a] and c) ,4. G. Brook
and J . M . Dufl, Can. J. Chem. 51.2024 (1973).
[ 3 ] a) M . A. Cook, C. Euhorn, A . E Jukcs,and D R . M.Wairon,J. Organometal
Chem. 24. 529 (1970): b) 0. W Strwurd, J . S . Johnson. and C . Eohorn.
ihid. 46. 97 (1972); c) 0. W Stvward and J . S. Johnson, h i d . 55. 209 (1973).
141 By reaction with an excess of paraformaldehyde. ( 5 ) has hitherto only
been accessible by multi-step syntheses: A . D. Petror, V F Mironor, and
V. G . Glukhoctsec. Otdel. Khim Nauk IY56, 461 ; Chem Abstr. 50, 16663 i
(1956); G. Frirz and J . Grobe, 2. Anorg. Allg. Chem. 309, 77 (1961). Pivalaldehyde (80°(,),benzaldehyde (71 %), cinnamaldehyde (51 %), and butanal
(43 %)can also be olefinated by ( 4 )
[5] D. J . Peterson, J. Org. Chem. 33, 780 (1968); D. Scubuch, M . Kolh.
and B. Th. GrLjhrl. Chem. Ber. 106, 2277 (1973). and further literature cited
84
Complexes of the type L,M--AsR2 (M =transition metal,
L=ligand; n=f(M))are regarded as being capable of existence
provided that electronegative substituents f R = CF3, C ~ F S ,
C1) reduce the donor strength of the As atom sufficiently to
suppress association uia ligand elimination producing doubly
bridged dinuclear or polymeric polynuclear complexes
[L, M-AsR,],"~21. That only bridged complexes have so
far been obtained in the case of compounds with R=CH,"!,
in spite of numerous attempted syntheses[3.'I, lends support
to this concept.
We have now found that under certain conditions (25"C,
12 h, nonpolar medium) mononuclear complexes of this type
with M=Cr, Mo, W, and Fe can be prepared in good yields
by use of the cyclopentadienylcarbonylmetalates and dimethylchloroarsane or by exchange reactions starting with
the analogous trimethylsilyl compounds[6!.
[T-C~H~(CO)~M]N~
B -C5H5(CO) .M-Si(CH,),
[*] Dr. W. Malisch and DiplLChem. M. Kuhn
Institut fur Anorganische Chemie der Universitat
X7 Wurzburg, Am Hubland (Germany)
Anguw. Chem. internal. Edit.
1 Vol. 13 (1974) 1 No.
1
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thein, synthesis, vinylsilanes, ketone, convenient, use
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