Cobalt(I)-catalyzed stereoselective olefination of alkylzinc reagents with aldehydes

Article abstract of DOI:10.1055/s-2003-40509

The efficient olefination from organozinc reagents with aldehydes is exploited in a new synthesis of aryl and alkyl olefins.

Full text of DOI:10.1055/s-2003-40509

1506
PAPER
Cobalt(I)-Catalyzed Stereoselective Olefination of Alkylzinc Reagents with
Aldehydes
C
obalt(I)-
i
C
atalyz
n
edStereosel
-
ective
O
X
lefination of
A
lkyl
i
z
inc Re
a
agents
w
it
n
A
ldehydes Wang,*a,b Ying Fu,a Yulai Hu,a Kehu Wanga
a
Institute of Chemistry, Department of Chemistry, Northwest Normal University, Lanzhou 730070, P. R. China.
Fax +86(931)7768159; E-mail: Wangjx@nwnu.edu.cn
b
State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, P. R. China.
Received 17 February 2003; revised 14 April 2003
reaction that allows the synthesis of (E)-alkenes from al-
dehydes with organozinc reagents under mild conditions.
Abstract: The efficient olefination from organozinc reagents with
aldehydes is exploited in a new synthesis of aryl and alkyl olefins.
Key words: alkenation, zinc, aldehydes, cobalt, organometallic re-
agents, alkenes
Olefinations are one of the most useful and fundamental
reactions in synthetic organic chemistry, particularly in
the synthesis of complex natural products with biological
activity. The well know Wittig reaction gives olefins by
introducing the double bond regio- and stereoselectively
and has found widespread application in synthetic organic
Scheme 1 Cobalt catalysed olefination
Table 1 Cobalt-Catalyzed Olefination of n-C8H17ZnI with p-Meth-
chemistry.1 Numerous reviews have detailed the progress oxybenzaldehydea
of the Wittig reagent.1 Many methods have been devel-
Entry Catalyst
Catalyst Solvent Temp
Yield of 3
(%)
oped for the olefination such as reductive coupling of car-
(mol%)
3.0
3.0
3.0
6.0
1.5
0
(°C)
bonyl compounds,2 self-coupling of -lithiated benzylic
sulfones,3 and condesation of aldehyde tosylhydrazones
1
2
[CoCl(PPh3)3]
THF
THF
THF
THF
THF
THF
THF
THF
DMF
r.t.
43
56
68
68
45
0
with stabilized carbanions.4 More recently, new proce-
dures for the synthesis of stilbenes have been reported, in
which aldehyde tosylhydrazones were treated with benzo-
triazole stabilized carbanions,5 trimethyl borate–lithium
tertbutoxide, trialkyl boranes, and alkylboron chlorides.6
[CoCl(PPh3)3]
[CoCl(PPh3)3]
[CoCl(PPh3)3]
[CoCl(PPh3)3]
[CoCl(PPh3)3]
[CoCl(PPh3)3]
[CoCl(PPh3)3]
[CoCl(PPh3)3]
[CoCl(PPh3)3]
[CoCl(PPh3)3]
[CoCl(PPh3)3]
[CoCl2(PPh3)2]
CoCl2
0
3
–18
–18
–18
–18
–18
–18
–18
0
0
0
0
0
0
0
0
0
0
0
0
4
5
The reaction of alkylzinc reagents and carbonyl com-
pounds represents one of the most reliable methods to pre-
pare optically active secondary alcohols.7,8 In addition, we
have also reported that the substitution reaction of nitro
group9 and dialkylation reaction10 of alkylzinc reagents
using [Ni(acac)2] as a catalyst in the presence of a tertiary
amine and silylating agent. Recently, we have reported the
stereoselective synthese of (E)-stilbenes11 by the reaction
of organozinc reagent with aryl aldehydes using
[Ni(acac)2] as a catalyst. However, our investigations
have shown that (E)-alkenes can be formed by the reac-
tion of organozinc halides with aldehydes in the presence
of a silylating agent and using [CoCl(PPh3)3] as the cata-
lyst.
6
7
3.0
3.0
3.0
3.0
3.0
3.0
3.0
3.0
38b
56c
60
52
58
42
54
0
8
9
10
11
12
13
14
MeCN –18
Et2O
C6H6
THF
THF
–18
–18
–18
–18
To our knowledge, the formation of (E)-alkenes by the re-
action of aldehydes and organozinc reagents, using this
catalyst in the presence of chlorotrimethylsilane is yet to
be reported. In this article, we wish to report our develop-
ment of an efficient [CoCl(PPh3)3] catalyzed olefination
a Unless other wise indicated, all reactions were conducted on the fol-
lowing scale: p-methoxybenzaldehyde (10 mmol), n-C8H7ZnI (11
mmol), cobalt catalyst and Me3SiCl (20 mmol), in solvent (20 mL)
for 8 h.
b Yield after 3 h.
c Yield after 6 h.
Synthesis 2003, No. 10, Print: 21 07 2003.
Art Id.1437-210X,E;2003,0,10,1506,1510,ftx,en;F01403SS.pdf.
© Georg Thieme Verlag Stuttgart · New York

PAPER
Cobalt(I)-Catalyzed Stereoselective Olefination of Alkylzinc Reagents with Aldehydes
1507
To demonstrate this concept, initial experiments exam- One advantage of this reaction, which makes it a particu-
ined the reaction of n-C8H17ZnI (1.1 equiv) with p-meth- larly attractive synthetic procedure, is its regiospecificity.
oxybenzaldehyde in the presence of various cobalt The double bond is formed between the carbonyl carbon
complexes and cobalt salt (Scheme 1). As summarized in atom of the aldehyde and the carbon atom of alkylzinc re-
Table 1, the (E)-1-(p-methoxyphenyl)-1-nonene is typical agent. The reaction is also stereoselective, in all cases
of an effective protocol for the (E)-alkene synthesis.
only the (E)-alkenes were isolated after chromatography.
[CoCl(PPh3)3] is superior to [CoCl2(PPh3)2] (Table 1, en- In the well-studied Wittig reaction, alkenes are usually
tries 3 and 13). The amount of [CoCl(PPh3)3] affected the formed in moderate-to-high yield as a mixture of E and Z
yield and the use of 3 mol% of the catalyst gave the best isomers, together with triphenylphosphine oxide as a by-
results (Table 1, entries 3–5). Further, the solvent influ- product.1a Our experimental results showed that this reac-
enced the reaction remarkably. When THF, DMF, Et2O, tion is highly stereoselective and gives only (E)-alkenes
MeCN and benzene were employed as a solvent, in the re- selectively.
action of n-C8H17ZnI with p-methoxybenzaldehyde in the
In summary, a new cobalt catalyzed olefination of alkylz-
presence of 3 mol% [CoCl(PPh3)3] and Me3SiCl, the
inc reagents with aromatic aldehydes has been developed
yields of the corresponding (E)-alkenes were 68, 60, 58,
that allows the synthesis of (E)-alkenes. The main advan-
52, and 42%, respectively (Table 1, entries 3, and 9–12).
tages of this new method are high stereoselectivity, toler-
THF was found to be the best solvent. We have also inves-
ance to unsaturated bonds and substituents, simple
tigated the effects of time and temperature on the reaction.
operation, and excellent product yields, all under relative-
It was found the highest yield of (E)-1-(p-methoxyphe-
ly mild reaction conditions.
nyl)-1-nonylene can be obtained at –18 °C to room tem-
perature for 8 h. When the reactions were conducted with
1H NMR spectra were recorded on Bruker AM 400 MHz and Bruk-
CoCl2 (Table 1, entry 14) and in the absence of
er AC-E 200 MHz spectrometers in CDCl3 with TMS as an internal
[CoCl(PPh3)3] and Me3SiCl (Table 1, entry 6), the reac-
tant aldehyde was recovered in >95%. We have found that
standard. 13C NMR spectra were obtained on a Bruker AM-400 op-
erating at 100 MHz or a Bruker AC-E 200 operating at 50 MHz. IR
this reaction is sensitive to the molecular structure of the
aldehydes and ketones. For example, under the same con-
ditions, the use of aliphatic aldehydes, ketones, and aro-
matic ketones led to several side reactions. The impact of
[CoCl(PPh3)3] and [NiCl2(PPh3)2]11 as catalysts for the
synthesis of compound 3a has been compared and the re-
sults showed that the yield of compound 3a was 69, and
67%, respectively. The [CoCl(PPh3)3] and [NiCl2(PPh3)2]
were found to be effective catalysts for the olefination re-
action.
spectra were recorded on an Alpha Centauri FI-IR spectrometer.
Mass spectra were recorded on a HP 5988A instrument. Elemental
analyses were carried out on a Carlo Erba-1106 instrument. Purifi-
cation of products was performed via flash chromatography with
200–400 mesh silica gel [petroleum ether (bp 60–90 ºC)–Et2O,
10:1]. All substrates and reagents were obtained commercially ex-
cept RZnI and [COCl(PPh3)3] which were prepared by standard pro-
cedures. THF was distilled from sodium–benzophenone. The
stereochemistry of the product olefins were determined by compar-
ison of the 1H NMR spectrum with that reported in the literature and
GC/MS analyses on a VG 7070E instrument.
In order to define the scope and limitation of this new
method for the (E)-alkenes synthesis, the reaction of vari-
ous aldehydes and organozinc reagents in the presence of
a silylation agent using [CoCl(PPh3)3] as catalyst were ex-
amined as shown in Scheme 2 and Table 2. We have also
found that the reaction of substituted aromatic aldehydes
with alkylzinc iodides in the presence of a catalytic
amount of [CoCl(PPh3)3] gives the corresponding (E)-alk-
enes in good to excellent yields (56–89%, Table 2, entries
1–15). Various substituents on the phenyl ring, such as
methyl, methoxyl, and benzyloxy could be tolerated and
had little effect on the yields. Unsaturated aldehydes, such
as phenylacrylic aldehyde, reacted similarly and provided
the corresponding (1E,3E)-1-phenyl-1,3-octadiene and
(1E,3E)-1-phenyl-1,3-(6,8,8-trimethyl)nonadiene in ex-
cellent isolated yield (Table 2, entries 13 and 14).
Olefins 3; Typical Procedure
Under an argon atmosphere, a mixture of zinc dust (0.85 g, 13
mmol), 1,2-dibromoethane (0.19 g, 1.0 mmol) and THF (2 mL) in a
three-necked flask was heated to 60–70 °C for 2–3 min and then
cooled to r.t. Chlortrimethylsilane (0.1 mL) was added, and the mix-
ture was stirred at r.t. for 15 min. A solution of RI (12 mmol) in THF
(10 mL) was then added, and the mixture was stirred for 12 h at
35 °C. The resulting solution of RZnI in THF was ready to use. In
another three-neck flask, [COCl(PPh3)3] (0.27 g, 0.3 mmol) and
THF (2 mL) were added and heated at 60 °C for 2 min. The solution
of RZnI in THF obtained above was added at r.t., and the resulting
mixture was cooled to –18 °C. A solution of aldehyde (10 mmol),
TMSCl (20 mmol) and THF (10 mL) was added in a few minutes
and the temperature was allowed to rise to r.t. After stirring for 12
h, sat. aq NH4Cl (10 mL), and Et2O (10 mL) were added and the
mixture was stirred for 10 min. The organic layer was separated,
dried over anhydrous MgSO4 and concentrated. The produce was
isolated from the crude reaction mixture by chromatography (silica
gel; petroleum ether–EtOAc).
(E)-1-Phenyl-1-heptene (3a)
Oil.12
IR: 3057, 3026, 2959, 2928, 2856, 1655, 1599, 1493, 1462, 964,
740, 692 cm–1.
Scheme 2 Synthesis of (E)-alkenes via alkylzinc reagents with al-
dehydes
Synthesis 2003, No. 10, 1506–1510 © Thieme Stuttgart · New York

1508
J.-X. Wang et al.
PAPER
Table 2 Cobalt(I) Complex Catalyzed Synthesis of (E)-Alkenes
Entry
1
Ar
Ph
R-FG
Producta
Yieldb (%)
n-C5H11
3a
3b
3c
3d
3e
3f
69
68
67
64
67
74
58
( )
3
2
3
4
5
6
7
Ph
n-C6H13
n-C7H15
n-C8H17
Cl(CH2)3
n-C5H11
n-C5H11
( )
4
Ph
( )
5
Ph
( )
6
Ph
Cl
( )
2
4-Me (C6H4)
2-MeO(C6H4)
( )
3
Me
3g
OMe
( )
3
8
2-MeO(C6H4)
n-C6H13
3h
56
OMe
( )
4
9
10
11
12
13
14
15
4-MeO(C6H4)
4-MeO(C6H4)
4-PhCH2O(C6H4)
4-MeO(C6H4)
PhCH=CH2
PhCH=CH2
Ph
n-C6H13
n-C8H17
n-C5H11
n-C7H15
n-C4H9
3i
74
68
89
68
65
56
65
( )
4
MeO
3j
( )
6
MeO
3k
3l
( )3
PhCH2O
MeO
( )
5
3m
3n
3o
( )2
EtO2CCH2
CO2Et
a E/Z ratios of isolated all products are 100:0.
b Isolated yield.
1H NMR (CDCl3, 200 MHz, TMS): = 7.18–7.39 (m, 5 H), 6.44 (d,
1 H, J = 16.0 Hz), 6.30 (dt, 1 H, J = 16.0 Hz), 2.05–2.41 (m, 2 H),
1.24–1.45 (m, 6 H), 0.91 (t, 3 H, J = 7.4 Hz).
(E)-1-Phenyl-1-octene (3b)
Oil.13
IR: 3059, 3025, 2956, 2925, 2854, 1650, 1598, 1494, 1462, 1377,
1297, 1256, 1209, 1172, 1069, 963, 844, 741, 692 cm–1.
EI-MS: m/z = 174 (M+, 4.2), 117 (100), 104 (61).
Synthesis 2003, No. 10, 1506–1510 © Thieme Stuttgart · New York

PAPER
Cobalt(I)-Catalyzed Stereoselective Olefination of Alkylzinc Reagents with Aldehydes
1509
1H NMR (CDCl3, 200 MHz, TMS): = 7.17–7.37 (m, 5 H), 6.43 (d,
1 H, J = 15.8 Hz), 6.27 (dt, 1 H, J = 15.8 Hz), 2.15 (q, 2 H, J = 5.8
Hz), 1.27–1.44 (m, 8 H), 0.89 (t, 3 H, J = 6.6 Hz).
6.71 (d, 1 H, J = 15.8 Hz), 6.31 (dt, 1 H, J = 16.0, 6.8 Hz), 3.87 (s,
3 H), 2.22 (q, 2 H, J = 6.8 Hz), 1.45–1.53 (m, 2 H), 1.30 (br s, 4 H),
0.92 (t, 3 H, J = 7.0 Hz).
EI-MS: m/z = 188 (M+, 20.8), 129 (6.0), 117 (100), 104 (86.2), 91
(52.1), 77 (11.1).
13C NMR (CDCl3, 50 MHz, TMS): = 156.2, 131.9, 127.7, 127.0,
126.3, 124.1, 120.6, 110.7, 55.4, 33.5, 31.8, 29.5, 22.6, 14.1.
EI-MS: m/z = 204 (M+, 99), 147 (100), 134 (66), 121, (65), 91 (95),
77 (11).
(E)-1-Phenyl-1-nonene (3c)
Oil.14
IR: 3058, 3021, 2955, 2925, 2855, 1644, 1597, 1492, 1457, 1374,
986, 745, 692 cm–1.
(E)-1-(2-Methoxyphenyl)-1-octene (3h)
Oil.
1H NMR (CDCl3, 200 MHz, TMS): = 7.10–7.38 (m, 5 H), 6.28 (d,
1 H, J = 15.8 Hz), 6.10 (dt, 1 H, J = 15.8 Hz), 2.19 (q, 2 H, J = 7.0
Hz), 1.05–1.60 (m, 10 H), 0.88 (t, 3 H, J = 6.6 Hz).
IR: 3032, 2955, 2925, 2854, 1647, 1597, 1579, 1489, 1462, 1437,
1377, 1290, 1243, 1177, 1104, 1053, 1031, 971, 844, 749, 579.0
cm–1.
13C NMR (CDCl3, 50 MHz, TMS): = 137.9, 131.1, 129.7, 128.4,
126.6, 125.8, 33.0, 31.8, 29.4, 29.3, 29.2 22.6, 14.0.
EI-MS: m/z = 202 (M+, 10.4), 131 (3.7), 117 (9.9), 104 (100), 91
1H NMR (CDCl3, 200 MHz, TMS): = 7.44 (dd, 1 H, J = 7.6, 1.8
Hz), 7.18 (qdd, 1 H, J = 8.0, 1.8, 0.4 Hz), 6.86 (qdd, 2 H, J = 7.6,
1.0, 0.4 Hz), 6.72 (d, 1 H, J = 16.0 Hz), 6.31 (dt, 1 H, J = 16.0, 6.8
Hz), 3.83 (s, 3 H), 2.24 (qd, 2 H, J = 6.8, 1.2 Hz), 1.16–1.63 (m, 8
H), 0.89 (t, 3 H, J = 7.4 Hz).
(45.4), 77 (9.7).
(E)-1-Phenyl-1-decene (3d)
EI-MS: m/z = 218 (M+, 68), 147 (100), 134 (34), 121, (35), 91 (41),
77 (14).
Oil.15
IR: 3061, 3026, 2956, 2924, 2853, 1601, 1493, 1461, 1377, 1303,
1161, 1028, 963, 742, 697 cm–1.
Anal. Calcd for C15H22O: C, 82.52; H, 10.16. Found: C, 82.43; H,
10.37.
1H NMR (CDCl3, 200 MHz, TMS): = 7.08–7.24 (m, 5 H), 6.38 (d,
1 H, J = 16.0 Hz), 6.10 (dt, 1 H, J = 16.0, 7.0 Hz), 2.19 (q, 2 H,
J = 7.0 Hz), 1.10–1.60 (m, 12 H), 0.90 (t, 3 H, J = 7.0 Hz).
(E)-1-(4-Methoxyphenyl)-1-octene (3i)
Oil.19
IR: 2926, 2854, 1610, 1584, 1511, 1463, 1382, 1345, 1247, 1175,
1098, 1039, 964, 831, 723 cm–1.
1H NMR (CDCl3, 200 MHz, TMS): = 7.17–7.32 (m, 4 H), 6.35 (d,
1 H, J = 15.8 Hz), 6.12 (dt, 1 H, J = 15.8, 6.6 Hz), 3.81 (s, 3 H), 2.20
(q, 2 H, J = 6.6 Hz), 1.10–1.41 (m, 8 H), 0.92 (t, 3 H, J = 6.4 Hz).
13C NMR (CDCl3, 50 MHz, TMS): = 137.9, 131.2, 129.7, 128.3,
126.7, 125.9, 33.0, 31.9, 29.4, 29.3, 29.1, 29.2, 22.6, 14.0.
EI-MS: m/z = 216 (M+, 8.2), 117 (65.3), 115 (24.5), 104 (100), 91
(30.8), 77 (4.7).
(E)-1-Phenyl-5-chloro-1-pentene (3e)
EI-MS: m/z = 218 (M+, 6.9), 147 (100), 134 (34), 121, (35), 91 (41),
77 (14).
Oil.16
IR: 3060, 3035, 2938, 2860, 2841, 1648, 1591, 1556, 1469, 1441,
966, 750, 694, 651 cm–1.
1H NMR (CDCl3, 200 MHz, TMS): = 7.17–7.37 (m, 5 H), 6.44 (d,
1 H, J = 16 Hz), 6.16 (dt, 1 H J = 16.0, 6.8 Hz), 3.57 (t, 2 H, J = 6.4
Hz), 2.37 (q, 2 H, J = 7.4 Hz), 1.62–1.92 (m, 2 H).
13C NMR (CDCl3, 50 MHz, TMS): = 137.4, 131.2, 128.6, 128.5,
128.3, 127.1, 126.1, 126.0, 44.3, 32.5, 29.7.
EI-MS: m/z = 182 (M+ + 2, 1), 180 (M+, 2), 117 (100).
(E)-1-(4-Methoxyphenyl)-1-decene (3j)
Oil.20
IR: 2927, 2855, 1610, 1511, 1465, 1370, 1301, 1240, 1174, 1090,
1040, 964, 831, 723, 574 cm–1.
1H NMR (CDCl3, 200 MHz, TMS): = 7.24 (dd, 2 H, J = 13.4, 6.8
Hz), 6.86 (t, 2 H, J = 8.2 Hz,), 6.35 (d, 1 H, J = 15.8 Hz), 6.12 (dt,
1 H, J = 15.8, 6.6 Hz), 3.81 (s, 3 H), 3.17–3.35 (m, 2 H), 1.45–1.88
(m, 2 H), 1.27 (br s 10 H), 0.92 (t, 3 H, J = 6.4 Hz).
13C NMR (CDCl3, 50 MHz, TMS): = 158.7, 135.4, 128.9, 128.1,
127.7, 113.5, 55.1, 33.0, 31.8, 29.5, 29.4, 29.3, 29.2, 22.6, 14.0.
EI-MS: m/z = 247 (M+ + 1, 3), 246 (M+, 11), 159 (2), 147 (100), 134
(E)-1-(4-Methylphenyl)-1-heptene (3f)
Oil.17
IR: 3021, 2956, 2925, 2855, 1652, 1612, 1512, 1464, 1378, 1305,
1209, 1175, 1106, 1039, 965, 824, 791, 726, 516 cm–1.
(22), 121, (51), 91 (24), 77 (9).
1H NMR (CDCl3, 200 MHz, TMS): = 7.22 (d, 2 H, J = 8.2 Hz),
7.08 (d, 2 H, J = 8.1 Hz), 6.34 (d, 1 H, J = 15.8 Hz), 6.14 (dt, 1 H,
J = 15.8, 6.8 Hz), 2.30 (s, 3 H), 2.11–2.20 (m, 2H), 1.28–1.54 (m, 6
H), 0.94 (t, 3 H, J = 7.4 Hz).
13C NMR (CDCl3, 50 MHz, TMS): = 136.3, 135.2, 129.8, 129.7,
129.2, 129.1, 125.3, 35.1, 31.5, 22.6, 21.2, 13.9.
(E)-1-(4-Benzyloxyphenyl)-1-heptene (3k)
Oil.
IR: 3035, 2828, 2742, 1689, 1601, 1573, 1505, 1455, 1424, 1391,
1304, 1257, 1219, 1161, 1110, 1021, 942, 906, 862, 826, 734, 694,
651, 513 cm–1.
1H NMR (CDCl3, 200 MHz, TMS): = 7.32–7.45 (m, 4 H), 7.26 (dt,
3 H, J = 8.8, 2.8 Hz,), 6.89 (dt, 2 H, J = 8.8, 2.8), 6.31 (d, 1 H,
J = 15.8 Hz), 6.06 (dt, 1 H, J = 15.8, 6.8 Hz), 5.04 (s, 2 H), 2.17 (q,
2 H, J = 6.6 Hz,), 1.40–1.51 (m, 2 H), 1.29 (br s, 4 H), 0.89 (t, 3 H,
J = 6.2 Hz).
EI-MS: m/z = 188 (M+, 16), 143 (4), 131 (100), 118 (46), 115 (24),
105 (16), 91 (32), 77 (9).
(E)-1-(2-Methoxyphenyl)-1-heptene (3g)
Oil.18
EI-MS: m/z = 280 (M+, 7), 225 (2), 198, (2), 121 (5), 91 (100), 77,
(5), 65 (8), 57 (3), 43 (4).
IR: 2925, 2854, 1597, 1489, 1461, 1438, 1291, 1243, 1178, 1104,
1031, 970, 844 cm–1.
1H NMR (CDCl3, 200 MHz, TMS): = 7.43 (dd, 1 H, J = 7.8, 1.8
Hz), 7.17 (qd, 1 H, J = 8.6, 1.8 Hz), 6.88 (qd, 2 H, J = 7.4, 1.1 Hz),
Anal. Calcd for C20H24O: C, 85.67; H, 8.63. Found: C, 85.78; H,
8.82.
Synthesis 2003, No. 10, 1506–1510 © Thieme Stuttgart · New York

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J.-X. Wang et al.
PAPER
(E)-1-(4-Methoxyphenyl)-1-nonene (3l)
Acknowledgment
Oil.21
This work was supported by the National Natural Science Founda-
tion of China (No.20272047) and the Northwest Normal University
Science and Technology Development Foundation of China
(KJCXGC-04).
IR: 2927, 2855, 1618, 1511, 1465, 1370, 1301, 1240, 1174, 1098,
1040, 964, 831, 723, 574 cm–1.
1H NMR (CDCl3, 200 MHz, TMS): = 7.23 (dt, 2 H, J = 8.2, 2.0
Hz), 6.86 (t, 2 H J = 8.4 Hz), 6.28 (d, 1 H, J = 15.8 Hz), 6.02 (dt, 1
H, J = 15.8, 7.2 Hz), 3.81 (s, 3 H), 2.17 (q, 2 H, J = 6.6 Hz), 1.08–
1.41 (m, 10 H), 0.89 (t, 3 H, J = 6.4 Hz).
References
13C NMR (CDCl3, 50 MHz, TMS): = 158.7, 135.4, 128.9, 128.1,
127.7, 113.5, 55.1, 33.0, 31.8, 29.5, 29.4, 29.2, 22.6, 14.0.
EI-MS: m/z = 232 (M+, 17.5), 147 (100), 134 (22.5), 121, (46.8), 91
(1) (a) Maryanoff, B. E.; Reitz, A. B. Chem. Res. 1989, 89, 863.
(b) Maercher, A. Org. React. 1965, 14, 270. (c) Johnson, A.
W. Ylid Chemistry; Academic Press: New York, 1966.
(d) Becker, K. B. Synthesis 1983, 341. (e) Burton, D. J.;
Yang, Z. Y.; Qiu, W. Chem. Rev. 1996, 52, 1641.
(f) Vedejs, E.; Marth, C. F. J. Am. Chem. Soc. 1988, 110,
3948.
(2) Mc Murry, J. E.; Fleming, M. P. J. Am. Chem. Soc. 1974, 96,
4708.
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(4) Vedejs, E.; Dolphin, J. M.; Stolle, W. T. J. Am. Chem. Soc.
1979, 101, 249.
(5) Katritzky, A. R.; Tymoshenko, D. O.; Belyakov, S. A. J.
Org. Chem. 1999, 64, 3332.
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1994, 59, 5530. (b) Kabalka, G. W.; Wu, Z.; Ju, Y.
Tetrahedron 2001, 57, 1663.
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(b) Noyori, R.; Kitamura, M. Angew. Chem., Int. Ed. Engl.
1991, 30, 34.
(24), 77 (7.0).
(1E,3E)-1-Phenyl-1,3-octadiene (3m)
Oil.22
IR: 3058, 3021, 2956, 2925, 2861, 1681, 1640, 1597, 1547, 1491,
1454, 1371, 1298, 1117, 1073, 1024, 986, 744, 691, 666, 617, 506
cm–1.
1H NMR (CDCl3, 200 MHz, TMS): = 7.22–7.48 (m, 5 H), 6.83
(dd, 1 H, J = 15.6, 10.2 Hz), 6.55 (t, 1 H, J = 15.6 Hz), 6.28 (dd, 1
H, J = 15.1, 10.2 Hz), 5.90 (dt, 1 H, J = 15.2, 7.0 Hz), 2.22 (q, 2 H,
J = 6.4 Hz), 1.41–1.50 (m, 4 H), 0.89 (t, 3 H, J = 6.6 Hz).
13C NMR (CDCl3, 50 MHz, TMS): = 137.7, 135.9, 130.5, 129.9,
129.4, 128.5, 127.0, 126.1, 32.6, 31.4, 22.2, 13.9.
EI-MS: m/z = 187 (M+ + 1, 3), 186 (M+, 19), 157 (2), 143 (43), 131
(13), 129 (100), 115 (31), 104 (11), 91 (26), 77 (11).
(8) (a) Dosa, P. I.; Fu, G. C. J. Am. Chem. Soc. 1998, 120, 445.
(b) Lutz, C.; Jones, P.; Knochel, P. Synthesis 1999, 312.
(9) Hu, Y.; Yu, J.; Yang, S.; Wang, J.-X.; Yin, Y. Synlett 1998,
1213.
(10) Hu, Y.; Wang, J.-X.; Li, W. Chem. Lett. 2001, 174.
(11) Wang, J.-X.; Fu, Y.; Hu, Y. Angew. Chem. Int. Ed. 2002, 41,
2757.
(1E,3E)-1-Phenyl-1,3-(6,8,8-trimethyl)nonadiene (3n)
Oil.
IR: 3059, 3022, 2954, 2867, 1681, 1596, 1493, 1465, 1363, 1245,
1199, 1124, 1070, 986, 902, 744, 691, 621, 566, 504 cm–1.
1H NMR (CDCl3, 200 MHz, TMS): = 7.19–7.45 (m, 5 H), 6.82
(dd, 1 H, J = 16.8, 10.2 Hz), 6.53 (t, 1 H, J = 16.8 Hz), 6.25 (dd, 1
H, J = 15.2, 10.2 Hz), 5.83 (dt, 1 H, J = 15.0, 7.0 Hz), 1.95–2.30 (m,
2 H), 1.62–1.78 (m, 1 H), 1.06–1.40 (m, 2 H), 0.91–1.04 (m, 12 H).
13C NMR (CDCl3, 50 MHz, TMS): = 137.6, 134.7, 131.7, 129.9,
129.4, 128.5, 127.0, 126.1, 50.5, 43.1, 31.1, 30.0, 22.5, 21.7.
EI-MS: m/z = 242 (M+, 5), 197 (2), 183 (1), 169 (1), 157 (1), 143
(12) Gerrard, A. F.; Djerassi, C. J. Am. Chem. Soc. 1969, 91,
6808.
(13) Meyers, A. I.; Ford, M. E. J. Org. Chem. 1976, 41, 1735.
(14) Citter, A.; Minisci, F.; Arnoldi, A.; Pagano, R.; Parravicini,
A.; Porta, O. J. Chem. Soc., Perkin Trans. 2 1978, 519.
(15) Ramart-Lucas, M.; Amagat, P. Bull. Soc. Chim. Fr. 1932,
965.
(16) Cowan, D. O.; Baum, A. A. J. Am. Chem. Soc. 1971, 93,
1153.
(17) Himmele, W.; Bott, K.; Bronstert, K. Eur. Pat. Appl.
EP314003, 1989; Chem. Abstr. 1989, 111, P194267w.
(18) Hu, Y.; Yu, J.; Yang, S.; Wang, J.-X.; Yin, Y. Synth.
Commun. 1999, 29, 1157.
(47), 128 (28), 117 (7), 104 (2), 91 (13), 77 (5), 57 (100), 41 (57).
Anal. Calcd for C18H26: C, 89.19; H, 10.81. Found: C, 89.07; H,
10.75.
(E)-4-Phenyl-3-ethylcrotonate (3o)
Oil.23
(19) Mori, A.; Suguro, M. Synlett 2001, 845.
(20) Seebach, D.; Schaefer, H.; Schmidt, B.; Schreiber, M.
Angew. Chem., Int. Ed. Engl. 1992, 31, 1587.
(21) Pelter, A.; Buss, D.; Colcough, E.; Singaram, B.
Tetrahedron 1993, 49, 7077.
IR: 3449, 2981, 2939, 2874, 1736, 1606, 1451, 1421, 1374, 1350,
1251, 1180, 1032, 919, 861, 750, 704 cm–1.
1H NMR (CDCl3, 200 MHz, TMS): = 7.17–7.39 (m, 5 H), 6.45 (d,
1 H, J = 15.8 Hz), 6.10 (dt, 1 H, J = 10.0, 7.0 Hz), 4.14 (q, 2 H,
J = 7.2 Hz), 3.17–3.32 (m, 2 H), 1.22 (t, 3 H, J = 7.0 Hz).
(22) Miyaura, N.; Yamada, K.; Suginome, H.; Suzuki, A. J. Am.
Chem. Soc. 1985, 107, 972.
EI-MS: m/z = 190 (M+, 19), 177 (2), 117 (100), 105 (21), 91 (23),
(23) Rudenko, M. G.; Soblev, Yu. P. Neftekhimiya 1996, 6, 312.
77 (16).
Synthesis 2003, No. 10, 1506–1510 © Thieme Stuttgart · New York