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Catalytic Lithiation of 1-Olefins.

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(2): Nucleoside ( I ) is lyophilized from benzene and then
dissolved in the stoichiometric amount of freshly distilled
styrene. After addition of 0.2% divinyl benzene and some
popcorn-polystyrene-seeds, the mixture is maintained at
5 0 ° C until the reaction had ceased (ca. 4 to 8 h). The polymer is thoroughly washed with benzene and ether and
dried in uucuo (yield almost quantitative). Cleavage of the
5'-U-protecting group follows by treatment with a 2% solution of benzenesulfonic acid in chloroform/methanoI
(7 :3 ; 1 h, OOC). After washing with methanol, chloroform
and ether and repeated drying, the support is ready for
use.
s-s-s
R
1
w
R
R
4
( l a ) , R' = R4 = CGH,, R2 = R3 = H
{ I h ) , R1 = R3 = CeH,, R2 = R4 = H
R3
Lithiation of ethylene with the catalysts prepared from
( l a ) , ZnCI, and lithium affords vinyllithium in 70-75%
yield, together with lithium hydride and small amounts
(2-3%) of I,o-dilithioalkanes121.The course of the reaction with time is illustrated in Figure 1.
H,C=CH, + 2 Li
cat.
THF
H,C=CHLi + LiH
Received: December 17, 1980 [Z 807b IE]
German version: Angew. Chem. 93, 709 (1981)
( l a ) , 78421-05-3; {lbj, 78421-06-4;[2~).78421-11-1; (2bj. 78421-09-7; styrene,
100-42-5; 5'-0-(4-hexadecyloxytrityl)thymidine, 78421-07-5; 4-vinylbenzoyl
chloride, 1565-41-9.
After completion of reaction H,C=CHLi can be separated from the precipitated LiH and isolated in crystalline
form as C2H3Li.THF.
[ I ] H. Seliger. M . Holupirek. H.-H. Gortz. Tetrahedron Lett. 1978, 21 15.
121 S.A . Narang, R . Brousseau. H. M . Hsiung, J . J Michniewicz. Methods
Enzymol. 65, 610 (1980); S. A. Narang. H . M . Hsiung. R . Brousseau. ibid.
68.90 (1980); H. Seliger. 7.C. Bach, E. Happ, M. Holupirek. E. H . Teufel.
Hoppe-Seylers Z. Physiol. Chem. 360, 1044 (1979).
(31 K . Miyoshi, K . Itakura. Tetrahedron Lett. 1979, 3635; M. J. Gait. M .
Singh. R . C. Sheppard, M . D. Edge. A . R . Greene, G. R . Heathclfle, T. C.
Atkinson, C. R . Newton, A . F. Markham, Nucleic Acids Res. 8, 1081
(1980); R. Crea. T. Horn, ibid. 8, 2331 (1980).
I41 J . W . Breitenbach, B. Herrmann, Angew. Makromol. Chem. 10, 197
(1970); R. L. Lefsmger. H . Seliger, Macromolecular Preprints, XXIII"'
International Congress of Pure and Applied Chemistry, Boston 1971,
1261.
IS] H.-H. Gortz, H. Seliger. Angew. Chem. 93, 708 (1981); Angew. Chem.
Int. Ed. Engl. 20, 681 (1981).
161 Y. Iwakura. K . Uno, N. Nakabayashi, ?i Korima. Bull. Chem. Soc. Jpn.
41, 186 (1968).
(-0-)
Catalytic Lithiation of 1-Olefins
By Borislav Bogdanovii and Bernd Wermeckes["
In 1967 D. L. Skinner et
described the reaction of
I-olefins with lithium to give I-lithio-1-alkynes and lithium
hydride, whereby (E)-1-lithio-1-alkenes are formed as byproducts. In 1975, V. Rautenstrauch'21 reported that small
amounts of I-lithioethylene and 1,4-dilithiobutane are
formed in the reaction of lithium with ethylene in dimethoxymethane or tetrahydrofuran (THF) in the presence of
biphenyl and naphthalene. Direct lithiation, however, has
so far been limited to "acidic" hydrocarbons such as I-alk y n e ~ ~ ~triphenylmethane'3b1
"',
or c y c I ~ p e n t a d i e n e [ ~ ' ~ ~ ~ .
In our studies on the catalytic properties of the poly(a1kali metal)
obtainable from 1,6,6ah4-trithiapentalenes ( I ) or related compounds and alkali metals, we
found catalysts for a direct reaction of 1-olefins with lithium to give organolithium compounds of the vinyl- and
allyl-type, respectively, and lithium h~dride'~"].
For the catalytic lithiation, the I-olefins were allowed to
react with lithium sand in THF at 0 ° C in the presence of a
catalytic amount of a 1,6,6ah4-trithiapentalene( I ) (or a related compound) and a metal salt[']. combinations of 2,5-16'
or 2,4-diphenyl-1,6,6ah4-trithiapentalene[6b' [(la) and
(Ib), respectively], anhydrous zinc- o r iron(ir1) chloride,
and lithium have proven to be particularly effective catalysts for the lithiation of olefins.
[*] Prof. Dr. E. Bogdanovic, Dr. B. Wermeckes
Max-Planck-Institut fur Kohlenforschung
Kaiser-Wilhelm-Platz 1, D-4330 Mulheim-Ruhr 1 (Germany)
684
0 Verlag Chemie GmbH. 6940 Wernheim. 1981
Fig. I . Plot of the lithiation of ethylene at O"C/I bar in T H F with time;
Li:(la):ZnC12=100:1 :2, [(laj]=0.04
mol/L;
(-0-1
Li : ( l a ) :ZnCI2=200: 1 :2, [(la)]=0.02 mol/L.
In the catalytic lithiation of propene the four isomeric
C3HSLi compounds (2)-(5) are formed along with LiH.
O n using the catalyst of combined ( l a ) , ZnClz and Li, the
C3HSLicompounds are obtained in a total yield of 7585%. The (E)-propenyllithium (2) is present up to 85-90%
in the mixture; it can be enriched to 98.5% by double recrystallization from THFIpentane (1 : 1).
CH&H=CH,
+
2 Li
cat./THF
- LiH
When combinations of ( l a ) or (lb), palladium(1l)- or platinum(i1) chloride and lithium are used as catalysts the
main product is (5). The highest selectivity for the formation of (5) (80-90%) has so far been achieved with the
complex (6)l7l, preparable from ( l a ) and PdCI,, as catalyst.
Analogously to propene, higher 1-olefins also react with
the catalyst from ( l a ) . ZnCI, and lithium to give (E)-l-lithio-I-alkenes. Moreover, the selectivity is higher than in
0570-0833/81/0808-0684 $02.50/0
Angew. Chem. Int. Ed. Engl. 20 (1981)
No. X
the case of propene; thus, I-butene, I-hexene and I-octene
can be catalytically lithiated to the products (7) with selectivities of 90-95, 95, and 94-97%, respectively.
R
H
H
H
)=(
+2~i----+
-LiH
Li
( 7)
R
=
(CH,),CH,;
n
=
1,3,5
I,w-Dienes (1,5-hexadiene and 1,7-octadiene) react with
lithium and the same catalysts to give a mixture of ( 4 - 1 - L
thio-lpalkadienes (8) and (E.E)-1,o-dilithio-1,w-alkadienes (9). The catalytic lithiation of lP-pentadiene, on the
other hand, leads to a crystalline trilithium compound
C5H5Li3,which according to 'H- and 13C-NMR data and
the results of silylation experiments has the constitution
trate is evaporated down again and the residue recrystallized 2-3 times (each recrystallization at -78°C) from
THF/pentane (1 : 1). After drying (0.2 torr), CLH3LiT H F is
obtained as colorless ~rystalsl'~!
C3HSLi:The lithiation of propene is carried out analogously to that of ethylene. The reaction mixture [(la)(2.20
g, 7.0 mmol), ZnC1, (1.93 g, 14.2 mmol), C3H6 (1 bar) and
lithium sand (4.89 g , 0.70 mol) in T H F (150 mL)] takes up a
total of 6.7 L of C3H6 (1 bar, 20°C) within 14 h. The reaction mixture is filtered. The overall yield of C3H5Licompounds (corresponding to their hydrolysis to propene) is
75% (referred to Li). Reaction of a part of the solution with
trimethylchlorosilane and gas-chromatographic analysis of
the silylation products formed['oc,'51gives the following
composition of C3H,Li compounds (in Yo): 89.8 (2). 0.5 (3),
1.9 (41, 7.8 (5). C,HSLi.THF is isolated in crystalline form
in the same way as described for C2H3Li.THF. After two
recrystallizations from THF/pentane (1 : I ) C3H,Li.THF is
obtained with 98.5% content of (2) (rest: 0.1% (3), 1.4Vo
(4))1161.
HXLi
+
(8)
2 Li
H
1"
the compounds @)-(lo) are new. Isobutene and
(Q-2-butene cannot be lithiated under analogous conditions (OOC, THF) and with the catalysts employed so far.
Organolithium compounds of the vinyl- and allyl-type
are finding ever increasing use as reagents in organic synthesesl'l. The (4-I-lithio-1-olefins (2) and (7) were previously synthesized'"] from (a-1-halo-I-alkenes by reaction with lithium"Oa-q, n-butyllithium"Ogl or tert-butyllithium"Oh-kl.(a-I-Halo-1-alkenes, on their part, are obtainable by hydroalumination or hydroboration of 1-alkynes
o r of their I-trimethylsilyl derivatives, followed by reaction
with halogens[Ioe.
, or by other methodsl'Oh.kl.
Catalytic lithiation opens u p a first direct entry to ( a - 1 lithio-1-olefins and hence also to (@-1,2-disubstituted olefins and derivatives
Procedure" 31
All reactions must be carried out under argon.C2H3Li: A solution of (la) (0.34 g , 1.1 mmol) and ZnCI,
(anhydrous; 0.30 g , 2.2 mmol) in anhydrous T H F (50 mL)
is saturated with ethylene (1 bar) at 0 ° C ; lithium sand
(1.45 g, 0.21 mol) is then added to the stirred solution under an atmosphere of ethylene. The uptake of ethylene,
which commences after 10- 15 min, is measured by means
of a gas burette. Until completion of reaction at 0 ° C a total of 2.28 L of ethylene ( 1 bar, 20°C) is taken up within 6
h (Fig. 1). The suspension is filtered and the separated LiH
washed with THF. Hydrolysis of a n aliquot of the filtrate
and mass spectroscopic analysis (MS) of the ethylene thus
liberated reveals a C2H,Li-yield of 75% (referred to Li).
The T H F solution is evaporated down under reduced pressure, the residue taken u p in ether/pentane (1 : I), and the
catalyst (violet precipitate) removed by filtration. The filAngew
Chem.
Int. Ed.
EnRI. 20 (1981) No. 8
C8H,5Li: Lithium sand (1.73 g, 249 mmol) is added with
stirring to a solution of I-octene ( I 1.55 g , 103 mmol), ( l a )
(0.32 g, 1.0 mmol) and anhydrous ZnClz (0.28 g, 2.0 mmol)
in T H F (100 mL) at 0°C. The reaction mixture is stirred
for 24 h at 0°C. The dark-violet suspension is removed by
filtration and the filtrate is evaporated to dryness at 0.2
torr; the distillate i s found by gas chromatography to contain T H F and 3.56 g of 1-octene (30.8% of that employed).
The residue is dissolved in ether and the resulting solution,
after treatment with trimethylchlorosilane (in excess) is
stirred for 12 h. It is then extracted with water, washed
neutral, dried with CaCI,, and the ether is distilled off at
normal pressure. Subsequent distillation under reduced
pressure affords, inter a h , 13.97 g of a fraction (b.p. 3543 "C/0.2 torr), which according to G C o r GC-MS analysis
consists of 74.8, 1.9,0.8, 0.4 and 0.4% of the isomeric trimethylsilyloctenes (MW = 184.4) (rest hexamethyldisiloxane).
The main component is (E)-1-trimethylsilyl-I-octene.
The
overall yield of C8H,5Li compounds is 83.2% (based on
reacted I-octene), with a selectivity of lithiation in the ( E ) I-position of 95.5%.
Received: December 23, 1980 [Z 794 IE]
German version: Angew. Chem. 93, 691 (1981)
CAS Registry numbers:
( l a ) , 1033-90-5; ( l b j . 14905-03-4; (2), 6386-72-7; (3). 6524-17-0; (4). 6386-716; (S), 3052-45-7: (6). 71328-64-8; (7) (R=CH,CH,), 67140-05-0; 17)
(R=(CH2),CH3), 62839-68-3; (7) (R=(CHZ)ICH1), 37730-25-9: (8).(n=2).
78371-49-0; (8) (n=4), 76814-25-0; (9) (n=2), 78371-SO-3; (9) (n=4), 7681426-1 ; (lo). 76814-27-2: vinyllithiurn, 917-57-7; ethylene, 74-85-1; propene,
115-07-1; I-butene, 106-98-9; I-hexene, 592-41-6: 1-octene, I 1 1-66-0: 1.5hexadiene, 592-42-7; 1,7-octadien, 37 10-30-3.
[ I ] D. L. Skinner. d. J Peterson, T. J. Logan, J. Org. Chem. 32. 105
(1967).
121 a) V. Raulenslrauch. Angew. Chem. 87, 254 (1975); Angew. Chem. Int.
Ed. Engl. 14, 259 (1975); b) Schweiz. Pat. 585760 (20. 5. 1974); Chem.
Abstr. 87, 135878 (1977).
131 a) H. Ogura. H. Takahashi. Synth. Commun. 3. 135 (1973); b) H . Gilman, B. J . Gaj. J . Org. Chem. 28. 1725 (1963); c) K . Hafner. H . Kaiser.
Justus Liebigs Ann. Chem. 618, 140 (1958); d) H . Gilman, R . D. Gorsich.
J. Org. Chem. 23, 550 (1958).
141 a) B. BogdanouiC, DOS 2 722221 (1978), Studiengesellschaft Kohle;
Chem. Abstr. 91, 39 135 (1979); b) B. Bogdanouii, DOS 2908928 (1980),
Studiengesellschaft Kohle.
151 Reaction of 1,6,6ah4-trithiapentalenesand 1,2-dithiol-3-thione derivatives with some heavy metal salts (FeCI,, CuC12, CuCI) affords 1 :2 adducts which can be used instead of the mixtures of the two components
for the preparation of the catalysts.
[6] a) G. Trauerso. Ann. Chim. (Rome) 44, 1018 (1954): b) E. Klingsberg. J.
Am. Chem. SOC.85, 3244 (1963).
0 Verlag Chemie GmbH, 6940 Weinheim, 1981
0570-0833/81/0808-068S !$02.50/0
685
[7] B . Bogdanouic, C. Kriiger. P. Locarelli, Angew. Chem. 91. 745 (1979);
Angew. Chem. Int. Ed. Engl. 18, 684 (1979).
(81 B. Wermeckes, Dissertation, Universitat Bochum 1979.
191 Nachr. Chem. Tech. Lab. 28, 78 (1980), and references cited therein.
[lo] a) D. Y. Curtin. J . W. Crump. J. Am. Chem. SOC.80,1022 (1958); b) N . L.
Allinger. R . B . Hermann, J. Org. Chem. 26. 1040 (1961); c) D. Seyferih,
L. G. Vaughan, J. Am. Chem. SOC.86. 883 (1964); d) G. M. Whitesides.
C. P. Casey. J. K . Krieger. ibid. 93. 1379 (1971); e) J. W . Patterson Jr.. J.
H . Fried. J. Org. Chem. 39, 2506 (1974); f) C. J. Sih, R. G. Salomon. P.
Price. R . Sood, G . Peruzzotli. J. Am. Chem. SOC.97, 857 (1975); g) A. F.
Kluge, K . G. Unlch, J . H . Fried. ibid. 94, 7827 (1972); h) E. J. Corey, D .
J. Beames, ibid. 94. 7210 (1972); i) E. J. Corey. H. S. Sachdeu. ibid. 95,
8483 (1973); j) C. J. Sih, J. 8. Heather, R . Sood. P. Price. G. Peruzzotti.
L. F. Hsu Lee, S. S . Lee. ibid. 97, 865 (1975); k) H . Neumann. D. Seebach. Chem. Ber. I l l , 2785 (1978), and references cited therein.
[ I 11 One route to (E)-I-lithio-I-alkenes which circumvents the (Q-I-halo-Iwith n-butylalkenes is the reaction of (E)-I-tri-n-butylstannyl-I-alkenes
lithium described by E. J . Corey and R . H . Wollenberg (J. Org. Chem.
40, 2265 (1975)).
1121 a) C. Zwe&fe/. C. C. Whitney. J. Am. Chem. SOC.89, 2753 (1967); b) H. C.
Brown. D . H . Bowman, S . Misumi. M . K . Unni, ibid. 89, 4531 (1967); c)
H.C. Brown, T. Hamaoka, N . Rauindran. ibid. 95, 5786 (1973); d) R . B.
Miller, T. Reichenbach, Tetrahedron Lett. 1974, 543.
1131 We wish to thank Frau Chem.-Tech. A. Marjanouit for valuable assistance in organizing the experimental procedures.
1141 3/4 of the vinyllithium present in solution could be isolated in this way;
C2H,Li.C4Hx0 (106.0); calc. 6.55% Li, obs. 6.56% Li; hydrolysis afforded 94% of the calculated amount of ethylene.
[IS] D. Seyferth, L. G. Vaughan, J. Organomet. Chem. I, 138 (1963).
[I61 Ca. 70% of (2) present in the solution could be isolated; C2HSLi.C,H80
(120.1); calc. 5.76% Li; obs. 5.75% Li.
Isomer Formation in the Cycloaddition Reaction of
2,7-Dimethyl-2,4,6-octatriene with
Tetracyanoethylene
By Alden D.Josey[''
Dimerization of isoprene in the presence of maleic anhydride bis(triphenylphosphane)palladium(o) occurs in a
linear, tail-to-tail fashion to give 2,7-dimethyl-1,3,7-octatriene, which under conditions of base-catalysis rearranges
to 2,7-dimethyl-Z,trans-4,6-octatriene
(la)"'. Isoprene is dimerized directly to ( l a ) by dad-modified chromium catalysts (dad = 1,4-diaza-1,3-diene)[2! Reaction of ( l a ) with tetracyanoethylene (TCNE) resulted in formation of the "expected" Diels-Alder adduct 3,3-dimethyl-6-(2-methyl-lpropenyl)-4-cyclohexene-l,1,2,2-tetracarbonitrile (4a)[z1.
The behavior of the triene in cycloaddition reactions
proved, however, to be somewhat different: (la) reacts
with T C N E to form two cycloadducts in amounts dependent on the polarity of the solvent.
In anhydrous solvents, equimolar amounts of ( l a ) and
T C N E produce an intense blue charge-transfer complex
whose color is discharged slowly, increases in intensity as
solvent is evaporated, and disappears completely o n removal of the solvent in uacuoP1.The crystalline residue
could be separated by extraction with hot hexane into two
isomeric compounds-the less-soluble (3a), m. p. = 140141.5 "C (from ethanol), and (4a), m.p. =90--92"C. Conversion was quantitative.
The isomers were identified by NMR and UV spectroscopyIa1.As indicated by the relative intensities of the 'HNMR signals at 6=3.55 (d, J = 10 Hz) and 4.15 (d, J = 10
Hz) of the non-olefinic ring H atoms of the [2 21-cycloadduct (3a) or of the normal [2+4]-cycloadduct (4a) in the
product mixture, formation of (3a) is favored by more polar solvents [(3a):(4a)= 33 :67 in tetrahydrofuran (THF),
+
[*I Dr. A. D. Josey
Experimental Station, E. I. du Pont de Nemours and Co.
Wilmington, Delaware 19898 (USA)
686
0 Verlag Chemie GmbH. 6940 Weinheim. 1981
SO : S O in acetonitrile], implicating (2) as a key intermediate.
NC C N
(30). R
=
R' = CH3
1
hR
R'
(la), R
(Ih), R
+
NC C N
V
,
T C N E . 7 >
=
R' CH3
=
H, R'= CH3
R R
(2)
That the cycloaddition of TCNE and substituted 1,3-butadienes leads to competing [2 21-42 + 41-cycloadditions
is well known e . g . the reaction of (5a) to (6a)-in which
the cyclobutane ring is closed at the less-hindered diene
terminus-and to (7a) [0% in nitromethane, 30% in cyclohexane]. Our own work shows that full methyl-substitution
of both diene termini in (Sb) does not hinder the reaction
but directs its course in CH,CN exclusively to the [2+2]adduct (66) in quantitative yieldf6'.
+
(>a),
R
(Sh), R
=H
= CH3
(6a), R
16h), R
= H
= CH,
(7tr), R
=
H
In the formation of (3a) electronic factors (hexadienyl
cation in (2)) alone cannot account for the regiospecificity
of the 12 21-cycloaddition toward the more hindered terminal double bond since the reaction of the less substituted triene (Ib) with T C N E results in exclusive formation
of the [2 41-adduct (4b)[').
It appears that the ability of the diene portion of the
polyene to assume a planar, or very nearly planar, cisoid
configuration in the transition state for cycloaddition
(good in (Ib), poor in (5b), intermediate in ( l a ) )must share
with electronic stabilization of intermediate ions the role
of determining how cycloaddition products are partitioned
into the two observed modes. The unusual triene ( l a ) represents a case in which these effects are sufficiently balanced to permit both reaction modes.
+
+
Received: February 25, 1980 [Z 795 I€]
German version: Angew. Chem. 93, 702 (1981)
[I] A . D.Josey. J. Org. Chem. 39, 139 (1974).
121 H. tom Dieck. A. Kinzel, Angew. Chem. 91. 344 (1979); Angew. Chem.
Int. Ed. Engl. 18. 324 (1979).
[3] 6.8 g (la) and 6.4 g TCNE (0.05 mol of each) in 75 m L THF or CH,CN;
the initially intense blue solution becomes pale green after 4 d at 25 "C
under N2.
[4] 'H-NMR (CDCI,. TMS int.): (3a) S = 1.48 (s, 3H). 1.53 (s, 3 H), 1.82 (s,
6H),3.55(d, IOHz, lH),5.3-6.9(m,3H);(4aJ6=1.67(s,3H),1.78(s,
3 H), 2.0 (m,6 H), 4.15 (d, 10 Hz, 1 H), 5.35 (d, 10 H I , 1 H), 5.4-5.95 (m,
2H, AB-system, 10 Hz; low- and high-field components exist as doublets
with J=2.0 or 1.5 H z splittings). UV (CH2C12): (3a) 1 = 2 6 3 nm
( E = 25 400).
0570-0833/81/0808-0686 $02.50/0
Angew. Chem. Ini. Ed. Engl. 20 (/98/)
No.X
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