Transition-metal catalyzed synthesis of δ-hydroxy-γ-lactones from bis(trimethylsilyl) ketene acetals and allylic acetates via γ-unsaturated carboxylic acids. Comments on the formation of α-cyclopropyl carboxylic acids

Article abstract of DOI:10.1016/S0022-328X(00)00905-0

Bis(trimethylsilyl)ketene acetals react with allylic acetates in the presence of Pd(0) complexes to give γ-unsaturated carboxylic acids together with α-cyclopropyl carboxylic acids. The unsaturated acids can be converted catalytically to δ-hydroxy-yγ-lactones by the H₂O₂/MTO system (methyltrioxorhenium) and to butenolides by Pd(II) catalyzed intramolecular cyclization reactions. The structure of two of these lactones has been established by X-ray analysis. The mechanism of the formation of the cyclopropanic acids will be discussed.

Full text of DOI:10.1016/S0022-328X(00)00905-0

Journal of Organometallic Chemistry 624 (2001) 186–202
www.elsevier.nl/locate/jorganchem
Transition-metal catalyzed synthesis of d-hydroxy-g-lactones from
bis(trimethylsilyl) ketene acetals and allylic acetates via
g-unsaturated carboxylic acids. Comments on the formation of
a-cyclopropyl carboxylic acids
Henri Rudler a,*, Paul Harris a, Andre´e Parlier a, Fre´de´ric Cantagrel a,
Bernard Denise a, Moncef Bellassoued b, Jacqueline Vaissermann c
a Laboratoire de Synthe`se Organique et Organome´tallique, UMR 7611, Uni6ersite´ Pierre et Marie Curie, 4 Place Jussieu,
75252 Paris Cedex 5, France
b Laboratoire de Chimie Organome´tallique associe´ au CNRS, Uni6ersite´ de Cergy Pontoise, 5 mail Gay-Lussac, Neu6ille-sur-Oise,
95031 Cergy-Pontoise Cedex, France
c Laboratoire de Chimie Inorganique et Mate´riaux Mole´culaires, ESA 7071, Uni6ersite´ Pierre et Marie Curie, 4 Place Jussieu,
75252 Paris Cedex 5, France
Received 3 October 2000; accepted 15 November 2000
Abstract
Bis(trimethylsilyl)ketene acetals react with allylic acetates in the presence of Pd(0) complexes to give g-unsaturated carboxylic
acids together with a-cyclopropyl carboxylic acids. The unsaturated acids can be converted catalytically to d-hydroxy-g-lactones
by the H2O2/MTO system (methyltrioxorhenium) and to butenolides by Pd(II) catalyzed intramolecular cyclization reactions. The
structure of two of these lactones has been established by X-ray analysis. The mechanism of the formation of the cyclopropanic
acids will be discussed. © 2001 Elsevier Science B.V. All rights reserved.
Keywords: bis(Trimethylsilyl)ketene acetals; Allylic acetates; Palladium; g-Unsaturated carboxylic acids; a-Cyclopropyl carboxylic acids; Methyltri-
oxorhenium; Lactones
intermediate must again be activated, for example by an
oxidation step. Such a scheme has been applied with
moderate success to the direct transformation of
arylethers into bicyclic lactones, in a one pot reaction,
upon their interaction with enolates originating from
bis(trimethylsilyl) ketene acetals [6–8].
According to Scheme 1, which describes this transfor-
mation, activation towards the first nucleophilic addition
is achieved classically via a chromium(0)tricarbonyl
complex. The intermediate potassium chromate is then
oxidized with iodine in order to promote the rearoma-
tization of the cyclohexadienyl group and release of the
metal. Since during this transformation the metal is likely
to be oxidized to Cr(II) [9], activation of the second
carbon of the double bond towards a second nucleophile
is again achieved: an intramolecular nucleophilic addi-
tion of the trimethylsilyl ester via an iodide assisted
oxygen–silicon bond cleavage could then take place.
1. Introduction
Functionalized g-lactones have important biological
properties and are also known as starting material for the
preparation of pharmacologically active compounds [1–
4]. Their synthesis by means of catalytic reactions thus
constitutes a worthwhile goal. As part of our interest in
the synthesis of saturated and unsaturated lactones, we
focused on d-hydroxy-g-lactones [5]. From a formal
point of view they can be considered as arising from a
double nucleophilic addition of the dianion of carboxylic
acids to a suitably activated carbonꢀcarbon double bond,
via a series of two nucleophilic additions. In order to be
able to perform the second nucleophilic addition, the first
* Corresponding author. Tel.: +33-1-4427-5092; fax: +33-1-4427-
5504.
E-mail address: rudler@ccr.jussieu.fr (H. Rudler).
0022-328X/01/$ - see front matter © 2001 Elsevier Science B.V. All rights reserved.
PII: S0022-328X(00)00905-0

H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
187
Scheme 1.
Scheme 2.
2. Results and discussion
Such a process might also be possible starting from a
suitably activated aliphatic carbon–carbon double
bond: for example an allylic acetate can be activated
catalytically towards nucleophiles via a p-allyl complex
[10,11] (Scheme 2).
The reaction between alkyl(trimethylsilyl) ketene ac-
etals and allylic carbonates in the presence of catalytic
amounts of Pd(0) complexes leading to g-unsaturated
carboxylic acid esters was initially disclosed by Tsuji
[14]. Subsequently, Musco found that allylic acetates
could be used for the same purpose [15] and that the
unsaturated esters were surprisingly found together
with a-cyclopropyl carboxylic acid esters in moderate
yields.
We have now established that for the direct synthesis
of g-unsaturated acids, bis(trimethylsilyl) ketene acetals
in conjunction with allylic acetates and Pd(PPh3)4 are
the suitable starting materials.
The interaction of a ketene acetal (or the enolate
therefrom) and this complex might then give a Pd(0)
p-complex. At this point, two possibilities exist: either
release of the metal to give the g-unsaturated carboxylic
acid (or its TMS ester) or reoxidation of the catalyst to
Pd(II) by the system Cu(II)/O2 followed by a Wacker-
type intramolecular nucleophilic addition [12]. This
might then lead directly to an unsaturated g-lactone. In
the first case, the g-unsaturated carboxylic acid might
also be transformed, by known routes, to d-hydroxy-g-
lactones, e.g. peroxy acid oxidation of the double bond,
followed by an intramolecular oxirane opening reaction
[13].
2.1. Formation of k-unsaturated carboxylic acids from
allylic acetates and bis(trimethylsilyl) ketene acetals
The purpose of this paper is twofold: first to demon-
strate that both of the coupled reactions, which rely on
known transformations, can be carried out catalyti-
cally, the first one involving only palladium, the second
one involving successively palladium and the system
H2O2/MTO.
Second, that during the first step, which leads to
g-unsaturated carboxylic acids, cyclopropyl carboxylic
acids are also formed as secondary products. The ratio
of the two products is essentially dependent on the
structure of the ketene acetals, and to a smaller extend,
on the reaction conditions.
In a preliminary communication [16], we already
described the preparation in moderate to good yields of
a series of g-unsaturated carboxylic acids by simple
heating THF solutions of the ketene acetals and the
allylic esters in the presence of 5% of the catalyst. We
also obtained a-cyclopropyl carboxylic acids, in vari-
able amounts, specific for some ketene acetals.
We have now observed that much better results can
be obtained by carrying out the reaction at lower
temperature, in refluxing dichloromethane. As can be
seen in Table 1 (entries 3 and 4), whereas for example
an overall 29% yield of the acids was observed for the

188
H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
Table 1
g-Hydroxy acids from allylic acetates and bis(trimethylsilyl)ketene acetals
Entry
R1
R2
R3
R4
Time (h)
Total yield (%)
Solvent
3
4
5
1
2
3
4
5
6
7
8
Me
Et
H
H
H
H
H
Me
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
Ph
Ph
H
H
16
47
20
16
16
16
20
22
72
50
15
72
16
20
19
16
69
22
20
20
96
120
72
19
25
4
61
34
29
52
49
70
24
98
98
42
76
40
100
0
79
65
27
81
66
95
40
70
91
95
93
80
18
77
96
35
68
91
86
60
67
70
80
60
THF
THF
THF
CH2Cl2
THF
THF
THF
CH2Cl2
THF
THF
Tol
THF
CH2Cl2
THF
CH2Cl2
THF
THF
CH2Cl2
THF
THF
THF
THF
THF
CH2Cl2
THF
CH2Cl2
THF
CH2Cl2
THF
THF
CH2Cl2
THF
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
THF
55
53
79
89
78
49
69
73
100
70
92
100
77
45
47
21
11
22
27
27
17
0
0
0
0
0
tBu
tBu
Ph
0
Me
24
14
10
0
0
0
(CH)5
(CH)5
9
Ph
Ph
H
H
H
H
H
H
H
Me
Me
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
OMe
OMe
OPh
OPh
Et
Et
Ph
Me
Me
30
8
0
0
0
23
88
100
76
67
76
100
100
94
0
0
0
0
0
0
0
0
12
0
24
33
24
0
0
6
15
0
0
0
0
0
0
0
0
0
0
(CH)5
Ph
Ph
H
H
Me
H
H
OMe
OPh
OPh
Me
Ph
Ph
Me
Me
Ph
OMe
OMe
OPh
OPh
OPh
Me
Me
CH2ꢁC(Me)
SiMe3
H
85
0
7
nPr
nPr
nPr
nPr
nPr
nPr
nPr
nPr
nPr
nPr
nPr
Ph
Ph
Ph
Ph
70:23
60:12
90:0
60:15
79.5:20
100
53:15
66:20
95
28
10
25
0.5
0
25
14
S
0
8
0
0
H
Me
Me
Ph
H
18
24
2
15
144
15
18
17
16
18
5
H
Me
Me
H
H
Me
H
100
82:10
30:70
100
100
70:30
0
0
0
0
0
0
H
17
THF
0
transformation of 1 and 2 into the regioisomers 3 and
4, the yield increased to 52% in dichloromethane in a
shorter reaction time.
substrates. A more striking example is found in entries
7 and 8, and 12 and 13, the yields varying respectively
from 24 to 98%, and from 40 to 100%.
This is a general trend except for the more elaborate
ketene acetals such as those derived from alkoxy and
aryloxy acids. Thus, no reaction at all was observed in
dichloromethane, whereas in THF a 42% and in tolu-
ene a 76% yield was obtained (entries 10 and 11).
Moreover, the reaction times were longer for these
For the g-unsaturated acids, two classes of isomers
are formed (Scheme 3 and Table 1):
“ regioisomers 3 and 4 arising from the fixation of the
enolate derived from the ketene acetals at the two
termini of the p-allyl ligand derived from the allylic
acetates. These were separated either by fractional

H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
189
crystallization or silica gel chromatography, or bet-
ter, were directly converted into lactones upon oxi-
dation (vide infra).
haviour of a series of linear allylic esters [19] which
gave cyclopropanes even in the presence of monoden-
tate phosphines. Several other examples involving p-al-
lyl complexes of palladium and either ketene acetals or
enolates of esters and ketones, and leading to cyclo-
propanes either in stoichiometric or in catalytic reac-
tions can be found and have been discussed in the
literature [20–29]. The beneficial role of s-donor lig-
ands such as amines (Et3N, TMEDA) has been ob-
“ E and Z stereoisomers 3a and 3b resulting from
double bond isomerisation.
As far as the regioisomers are concerned, their ratio
is highly dependent, as expected, on the size of the
substituents on the starting ketene acetals, the amount
of isomers arising from a SN2% reaction increasing when
the size of these substituents decrease. This appears
clearly for example in the entries 1 and 12, the ratios
being respectively, for R1=Me and R2=H, 55:45, and
for R1=OPh and R2=H, 100:0, for the same sub-
strate, cinnamyl acetate.
A second observation should be put to the fore: side
reactions are also observed, e.g. formation of a,b-unsat-
urated acids derived from the ketene acetals. Thus for
R1=Et and R2=H (entry 14), significant amounts of
crotonic acid were formed as the result of an oxidation
reaction. This transformation takes place when the
reaction is carried out in THF, no secondary products
being observed in dichloromethane (entry 15). Such a
transformation can be related to the formation of a,b-
unsaturated carbonyl compounds from silyl enol ethers
derived from ketones, as described by Tsuji [17].
served. Moreover,
a palladacyclobutane could be
isolated by Hoffmann upon interaction of a preformed
p-allyl complex bearing the TMEDA ligand with a
ketone enolate. Its transformation in the presence of
CO led to the expected, substituted cyclopropane [22].
We have now found in several instances the forma-
tion of up to 33% of cyclopropyl carboxylic acids
together with the expected g-unsaturated acids in the
absence of any added base. Increasing amounts of
cyclopropane derivatives were formed upon increasing
the number and the size of the substituents on the
b-carbon of the ketene acetals. As can be seen for
example in the entries 6, 17, 18 and 19, the ketene
acetals 1 (R1=R2=Me and R1R2=(CH2)5) gave
about the same yield (24%) of a-cyclopropyl carboxylic
acid 5,
a yield which increased to 33% when
dichloromethane was used instead of THF. The trans
stereochemistry of 5 (R1, R2=Me, R3=Ph) has been
established by DEPT, 1H–13C-NMR correlation and
DNOES experiments. Since separation of the unsatu-
rated carboxylic acids from cyclopropanic acids is ex-
ceedingly difficult using silica gel chromatography, it
was desirable to increase the yield of the latter com-
pounds. Since the use of nitrogen-containing bidentate
ligands has been found to favour the formation of
cyclopropanes, we reacted allyl acetate and dimethyl-
bis(trimethylsilyl)ketene acetal 1 (R1=R2=Me) in
refluxing dichloromethane in the presence of 3%
Pd2(dba)3 and 15% TMEDA. Gratifyingly, the cyclo-
propane was formed as almost the sole product (90%)
although the overall yield was only moderate (44%). It
is clear that TMEDA has a positive effect in the
2.2. Formation of h-cyclopropylcarboxylic acids
According to Tsuji [14] and subsequently reported by
Morimoto [18], the interaction of alkyl(trimethylsilyl)
ketene acetals with allylic carbonates led exclusively to
unsaturated carboxylic acid esters. In contrast however,
Musco and coworkers first found that cyclohexenyl
acetates and methyl(trimethylsilyl) ketene acetals re-
acted in THF to give bicyclo [3.1.0] hexane derivatives
in significant amounts, in addition to the expected
unsaturated esters [15]. However, this transformation
took place only in the presence of bidentate phospho-
rus-containing ligands, no reaction being observed in
the presence of the monodentate ligand triphenylphos-
phine. Later on, these authors observed the same be-
Scheme 3.

190
H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
During our investigations directed towards the use of
H2O2 and methyltrioxorhenium (MTO) [32,33] as cata-
lyst for the synthesis of acid sensitive epoxides [34], we
found that such species could be prepared in the pres-
ence of pyridines, in a biphasic medium (H2O2/CH2Cl2).
Especially rewarding was the synthesis of epoxides
derived from g-unsaturated alcohols. Indeed, in the
absence of these additives, intramolecular ring-opening
of the oxiranes, leading to b-hydroxy tetrahydrofuranes
were observed. We could establish that this reaction
was catalyzed by MTO, which acts as a Lewis acid
(Scheme 4).
Scheme 4.
Such an intramolecular reaction could also be ap-
plied successfully to the synthesis of d-hydroxy-g-lac-
tones from g-unsaturated carboxylic acids by using the
following general procedure. Thus, MTO (0.36 mmol)
was added to a mixture of unsaturated and cyclo-
propanic acids (7.3 mmol, 85/15) in chloroform (20 ml).
Aqueous H2O2 (30%, 1.1 equivalents) was then added
at room temperature and the solution stirred vigorously
until the disappearance of the olefinic protons in the
1H-NMR spectrum. Any remaining H2O2 was then
decomposed either with dilute thiosulphite or with
MnO2. The organic layer was removed and the aqueous
layer was treated with aqueous base then extracted with
dichloromethane. The organic layers were dried and the
products purified by column chromatography. The d-
hydroxy-g-lactones were obtained almost quantitatively
(80–95% yield), and depending on the substituents,
either as single isomers, as positional isomers or as
diastereoisomers (see Section 4). Similar results have
recently been disclosed by Espenson [35].
formation of cyclopropanes although the structure of
the ketene acetals appears according to this report as
well as in the results of Musco [15,19] as fundamental.
Even a monosubstituted ketene acetal (R1=Et, entry
15) also gave 5 in a low 12% yield. Whereas in the case
of the methoxy substituted ketene acetal 1 (R1=OMe,
entry 21) no cyclopropyl carboxylic acid 5 could be
detected, a 15% yield of 5 was again observed for the
phenoxy-substituted ketene acetal 1 (R1=OPh, R2=
Me, entry 23).
Compounds 5 could be easily separated from the
unsaturated acids upon transformation of these latter
into lactones (vide infra).
In summary, all these experimental results confirm
“ that no added base is necessary for the interaction of
ketene acetals with allylic acetates [25].
“ that no nitrogen-containing ligand is essential for the
observation of the cyclopropanes but that TMEDA
has a positive effect in their formation.
“ but conversely, that the nature of the substituents on
the ketene acetals and the allylic acetates is crucial
for the outcome of the reaction: sterically demanding
groups in one or the other reacting substrates favour
the formation of the cyclopropyl carboxylic acids.
The cyclopropyl carboxylic acids were recovered
quantitatively by acidification of the aqueous layer
followed by extraction with dichloromethane.
2.3.2. Intermediate formation and detection of an
epoxide
2.3. Catalytic synthesis of l-hydroxy-k-lactones from
k-unsaturated carboxylic acids
According to the above procedure, the unsaturated
acid 3a led, after 24 h, to the hydroxy lactone 7a as a
solid, m.p. 52°C. Its H-NMR spectrum confirmed the
1
presence of a secondary benzylic alcohol with a doublet
at l 5.13, and of an ether linkage, with a signal as a
multiplet at l 4.60 Eq. (1).
2.3.1. A two-step procedure in6ol6ing palladium and
methyltrioxorhenium
The formation of lactones from unsaturated car-
boxylic acids is a well recognized and very useful bond
construction process in organic synthesis.
Several methods exist for this transformation. The
most popular is the halolactonization reaction which
leads either to halolactones or to saturated lactones
[30,31].
Other methods involve the intramolecular opening of
transient epoxides which are formed upon reaction of
the carbon–carbon double bond with peroxyacids [12]
and lead to d-hydroxy-g-lactones.
(1)
When the course of the reaction was carefully moni-
1
tored by H-NMR spectroscopy, an intermediate epox-
ide 6a, which disappeared progressively in favour of the

H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
191
hydroxy lactone 7a, could be detected: signals at l 4.93
(d) and at 3.95 (m) confirmed such a structure.
The structure and the stereochemical outcome of
these intramolecular reactions was confirmed by two
X-ray analyses carried out on the lactones 7b and 7c.
Their molecular structures appear respectively in the
Figs. 1 and 2 and the crystallographic data are reported
in Tables 2 and 3 Eq. (2)Eq. (3).
(2)
Fig. 1. Molecular structure of the hydroxy lactone 7b.
Fig. 2. Molecular structure of the hydroxy lactone 7c.

192
H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
Table 2
This might be possible since Wacker-type cycliza-
tions, induced by palladium(II) are known for both
unsaturated phenols and carboxylic acids [37,38]. They
lead, respectively, to unsaturated furanes and unsatu-
rated lactones.
We found on a few preliminary examples that such a
transformation could also be carried out on the unsatu-
rated carboxylic acids synthesized herein.
Crystallographic data for compound C16H20O3 (7b)
Fw
T (K)
Crystal system
Space group
Unit cell dimensions
260.3
295
Triclinic
(
P1
,
a (A)
6.162(5)
,
b (A)
10.749(4)
11.146(4)
74.44(3)
74.65(6)
88.73(7)
684.8(7)
2
0.80
1.26
CAD4 Enraf-Nonius
0.71069
ꢀ/2q
0.8+0.345 tgq
1–28
0, 8; −13, 14; −14, 14
3601
Two approaches have thus been made:
,
c (A)
h (°)
i (°)
“ first, the isolated carboxylic acids were heated to
60°C in DMF, in the presence of a catalytic amount
of Pd(II) complexes (Na2PdCl4, PdCl2(PPh3)2), to-
gether with Cu(OAc)2 and oxygen. This gave the
expected unsaturated lactones 8a and 8b in fairly
good yields. The presence of DMF appeared to be
critical since almost no lactones were formed in
solvents such as THF. Whereas in the presence of
Na2PdCl4 a 55:45 mixture of two lactones was ob-
tained, in 81% yield, in the case of PdCl2(PPh3)2 the
exo-methylene butenolide 8a was almost the sole
product of the reaction (Scheme 5).
k (°)
3
,
V (A )
Z
Linear absorption coefficient v (cm−1
)
Density z (g cm−3
)
Diffractometer
Radiation (Mo–Ka), l (A)
Scan type
Scan range (°)
q limits (°)
,
Octants collected
No. of data collected
No. of unique data collected
3296 (Rint=0.01)
“ second, attempts were made to use the palladium
already present in the crude reaction mixture from
No. of unique data used for refinement 1814 (Fo)2\3|(Fo)2
R=ꢀꢁꢁFoꢁ−ꢁFcꢁꢁ/ꢀꢁFoꢁ
Rw a=[ꢀ w(ꢁFoꢁ−ꢁFcꢁ)2/ꢀwF2o]1/2
S
0.0517
0.0686
1.10
None
233
Table 3
Extinction parameter
No. of variables
Crystallographic data for compound C20H22O3 (7c)
Dzmin (e A−3
)
)
−0.22
0.41
Fw
310.4
Dzmax (e A−3
T (K)
295
Crystal system
Space group
Unit cell dimensions
Monoclinic
P21/n
a w=w%[1-((ꢁꢁFoꢁ−ꢁFcꢁꢁ)/6|(Fo))2]2 with w%=1/ꢀr ArTr(X) with
three coefficients 8.51, 2.62 and 7.08 for a Chebyshev Series, for
which X is Fc/Fc(max).
,
a (A)
8.739(2)
19.612(6)
9.961(2)
90
98.18(2)
90
1689.7(7)
4
,
b (A)
,
c (A)
h (°)
i (°)
k (°)
(3)
3
,
V (A )
Z
Linear absorption coefficient v (cm−1
)
0.75
1.22
Density z (g cm−3
)
As can be seen in both structures, the lactones arising
from the two trans olefins led to hydroxylactones in
which the hydroxyl group is anti with respect to the
carbon–oxygen bonds of the bridging ether linkage
confirming the anti-5-exo tet cyclization mode [36].
A series of other lactones bearing various sub-
stituents was obtained according to the above proce-
dure confirming the general scope of the
transformation. Their physical data can be found in
Section 4.
Diffractometer
Radiation (Mo–Ka), l (A)
Scan type
Scan range (°)
q limits (°)
CAD4 Enraf-Nonius
0.71069
ꢀ/2q
0.8+0.345 tgq
1–26
0, 10; 0, 24; −12, 12
3655
,
Octants collected
No. of data collected
No. of unique data collected
3311 (Rint=0.01)
No. of unique data used for refinement 1582 (Fo)2\3|(Fo)2
R=ꢀꢁꢁFoꢁ−ꢁFcꢁꢁ/ꢀꢁFoꢁ
Rw a=[ꢀ w(ꢁFoꢁ−ꢁFcꢁ)2/ꢀwF2o]1/2
S
0.0651
0.0810
1.10
Extinction parameter
No. of variables
512
210
−0.27
0.34
2.3.3. A two-step procedure in6ol6ing only palladium
Since the first step of the transformation of g-unsatu-
rated carboxylic acids involves palladium, it would be
highly advantageous to use the same metal to carry out
the second step of the transformation, the intramolecu-
lar cyclization.
Dzmin (e A−3
)
)
Dzmax (e A−3
a w=w%[1-((ꢁꢁFoꢁ−ꢁFcꢁꢁ)/6|(Fo))2]2 with w%=1/ꢀr ArTr(X) with
three coefficients 5.68, 0.250 and 4.01 for a Chebyshev Series, for
which X is Fc/Fc(max).

H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
193
drawing of the molecules was carried out with the
CAMERON program [55].
4. Experimental
General: all reactions were performed under a dry
argon atmosphere. Solvents were distilled from sodium/
benzophenone ketyl (diethyl ether, tetrahydrofurane),
phosphorus pentoxide (dichloromethane) and saturated
with argon. Silica gel (Merck, type 60, 0.063–0.200
Scheme 5.
1
mm) was used for column chromatography. H-NMR:
the first transformation: no reaction was observed in
THF, in the presence of Cu(II) and oxygen. How-
ever, when THF was exchanged for DMF, and the
reaction conducted under the same conditions as
above, conversion into the lactone was again ob-
served. Thus, the solution resulting from the interac-
tion of the ketene acetal 1 (R1=R2=Me) and allyl
acetate was freed from THF. DMF was then added
together with Cu(OAc)2 and the solution heated to
80°C in the presence of oxygen for 5 h. Workup led
to a single lactone 8a (80%).
Bruker ARX-400 (400 MHz), DPX 250 (250 MHz),
AC-200 (200 MHz). 13C-NMR: Bruker ARX-400 (100
MHz), DPX-250 (60 MHz), AC-200 (50 MHz). All
NMR spectra were recorded in CDCl3 unless stated
otherwise with CHCl3 as internal standard. MS and
HRMS were recorded on a JEOL MS 700. Melting
points were performed on a Reichert apparatus and are
uncorrected. TLC: 0.25 mm Merck silica gel plates 60
F254
.
The bis (trimethylsilyl) ketene acetals were prepared
according to the literature [39].
4.1. Typical experimental procedure for the Pd
catalyzed reactions
3. Conclusion
Direct access to a series of unsaturated carboxylic
acids and d-hydroxy-g-lactones from allylic acetates
and bis(trimethylsilyl)ketene acetals has been achieved
by the use of two coupled catalytic reactions involving
palladium(0) and oxorhenium catalysts. In addition to
the unsaturated carboxylic acids, cyclopropane car-
boxylic acids were obtained. The yield of this latter
compounds was highly dependent on the structure of
the starting ketene acetals. A mechanism for their for-
mation involving intermediate palladacyclobutanes has
been tentatively suggested.
To an oven-dried 50 ml flask was added under an
argon atmosphere the acetate (3 mmol), the acetal (3.30
mmol), Pd(PPh3)4 (5 mol%) and a solvent (20 ml). A
reflux condenser was fitted and the solution was stirred
and refluxed until complete consumption of the starting
acetate as judged by 1H-NMR. The solution was cooled
to room temperature, the solvent removed and the
residue filtered through a short pad of silica gel (70/30
ether/petroleum ether) to remove palladium complex
and triphenyl phosphine. The products were then
purified by either column chromatography (ether/
petroleum ether) or acidbase workup.
3.1. Structure solution and refinement
4.2. 2-Methyl-5-phenyl-pent-4-enoic acid [40]
For products 7b and 7c, accurate cell dimensions and
orientation matrices were obtained by least-squares
refinements of 25 accurately centered reflections. No
significant variations were observed in the intensities of
two checked reflections during data collection. Com-
plete data and collection parameters are listed in Tables
2 and 3. The data collected for Lorentz and polariza-
tion effects. Computations were performed by using the
PC version of CRYSTALS. [52] Scattering factors and
corrections for anomalous absorption were taken from
[53] . The structures were solved by Fo–Patterson
technique or direct method (SHELXS) [54]. Refinements
were carried out by full-matrix least-squares. All non-
hydrogen atoms were anisotropically refined, hydrogen
atoms were introduced in calculated positions. The
1H-NMR (200 MHz, CDCl3) l: 7.38–7.20 (m, 5H,
Ph), 6.47 (d, 1H, J=16 Hz, Ph–CH
J=16 Hz, J=8 Hz, Ph–CHꢁCH), 2.62 (m, 2H, CH2),
1.3 (m, 1H, CH
), 1.24 (d, 3H, J=8 Hz, CH3). 13C-
NMR (100 MHz, CDCl3) l: 182.3 (CO), 137.4 (CPh),
132.5 (Ph–CHꢁ), 128.8–126.3 (C Ph+Ph–CHꢁCH),
39.6 (C–COOH), 36.8 (CH2), 16.6 (CH3).
6 ꢁ), 6.19 (dt, 1H,
6
6
6
6
6
4.3. 2-Methyl-3-phenyl-pent-4-enoic acid [40]
4.3.1. h Diastereoisomer
1H-NMR (400 MHz, CDCl3) l: 7.38–7.20 (m, 5H,
Ph), 6.20–5.80 (m, 1H, CH2ꢁCH
6
), 5.20–5.00 (m, 2H,
6 ), 2.70–2.30 (m,1H,
CH2ꢁCH), 3.6 (m, 1H, Ph–CH
6

194
H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
CH
(100 MHz, CDCl3) l: 182.0 (CO), 141.2 (CPh), 139.5
(CH2ꢁCH), 128.8–126.3 (CPh), 115.9 (CH2ꢁCH), 53.4
(Ph–CH), 44.8 (C–COOH), 15.6 (CH3).
6
–COOH), 1.3 (d, J=8 Hz, 3H, CH3). 13C-NMR
MHz, CDCl3) l: 178.5 (CO), 138.5, 136.6, 128.9–126.3,
(CPh), 132.8 (CH2ꢁCH), 118.1 (CH2ꢁCH), 57.2, 52.7
(Ph–CH).
6
6
6
6
6
6
6
4.8.2. i Diastereoisomer
1H-NMR (400 MHz, CDCl3) l: 7.36–7.00 (m, 10H,
Ph), 5.00 (ddd, 1H, J=17.2 Hz, J=10.2 Hz, J=7.2
4.3.2. i Diastereoisomer
1H-NMR (400 MHz, CDCl3) l: 7.38–7.20 (m, 5H,
Hz, CH2ꢁCH
CHHꢁCH), 5.03 (dd, 1H, J=17.2 Hz, J=1.2 Hz,
CHHꢁCH), 3.91 (m, 2H, Ph–CH
). 13C-NMR (100
MHz, CDCl3) l: 178.5 (CO), 138.5, 136.6, 128.9–126.3,
(CPh), 132.8 (CH2ꢁCH), 118.1 (CH2ꢁCH), 57.2, 52.7
(Ph–CH).
6 ), 5.13 (dd, 1H, J=10.2 Hz, J=1.2 Hz,
Ph), 6.20–5.80 (m, 1H, CH2ꢁCH
CH2ꢁCH), 2.90 (m, 1H, Ph–CH
CH
(100 MHz, CDCl3) l: 181.4 (CO), 141.0 (CPh), 138.4
(CH2ꢁCH), 128.8–126.3 (CPh), 117.1 (CH2ꢁCH), 53.3
(Ph–CH), 45.3 (C–COOH), 16.0 (CH3).
6
), 5.20–5.00 (m, 2H,
6 ), 2.70–2.30 (m, 1H,
6
6
–COOH), 1.0 (d, J=8 Hz, 3H, CH3). 13C-NMR
6
6
6
6
6
6
6
6
6
6
4.9. 2,2-Dimethyl-5-phenyl-pent-4-enoic acid (m.p.
38°C) [41]
4.4. 2-Ethyl-5-phenyl-pent-4-enoic acid [41]
1H-NMR (200 MHz, CDCl3) l: 7.41–7.24 (m, 5H,
1H-NMR (400 MHz, CDCl3) l: 7.31–7.11 (m, 5H,
Ph), 6.36 (d, 1H, J=16 Hz, Ph–CHꢁ), 6.11 (dt, 1H,
Ph), 6.50 (d, 1H, J=16 Hz, Ph–CH
J=16 Hz, J=8 Hz, Ph–CHꢁCH), 2.62 (m, 2H, CH2
1.3 (m, 3H, CH–COOH+ꢁCH–CH2), 1.71 (m, 2H,
CH2–CH3), 1.02 (t, 3H, J=8 Hz, CH3).
6
ꢁ), 6.23 (dt, 1H,
6
6
),
J=16 Hz, J=7.5 Hz, Ph–CHꢁCH6 ), 2.39 (d, 2H,
6
6
J=16 Hz, CH2), 1.17 (s, 6H, CH3). 13C-NMR (100
MHz, CDCl3) l: 184.8 (CO), 137.6, 129.0, 127.5, 126.5
6
(CPh), 133.7, 126.1 (CHꢁ), 43.9 (CH2), 43.0 (C6 –
4.5. 2-Terbutyl-5-phenyl-pent-4-enoic acid
COOH), 25.1 (CH3). Anal. Calc. for C13H16O2: C,
76.47; H, 7.84. Found: C, 75.85; H, 8.20%. HMRS
Calc. for C13H16O2, 204.1229. Found, 204.1226.
1H-NMR (400 MHz, CDCl3) l: 7.29–7.21 (m, 5H,
Ph), 6.47 (d, 1H, J=15.8 Hz, Ph–CH), 6.15 (m, 1H,
Ph–CHꢁCH
6
), 2.52–2.45 (m, 2H, CH2), 2.35 (dd, 1H,
–COOH), 1.07 (s, 9H,
4.10. 2,2-Dimethyl-3-phenyl-pent-4-enoic acid
J=11.6 Hz, J=4.1 Hz, CH
6
CH3). HMRS Calc. for C15H19O2, 231.1385. Found,
231.1386.
1H-NMR (400 MHz, CDCl3) l: 7.40–7.11 (m, 5H,
Ph), 6.25 (m, 1H, CH2ꢁCH6 ), 5.17 (m, 2H, CH6 2ꢁCH),
3.67 (d, 1H, J=9.9 Hz, Ph–CH), 1.29, 1.28 (s, 6H,
4.6. 2-Terbutyl-3-phenyl-pent-4-enoic acid
CH3). 13C-NMR (100 MHz, CDCl3) l: 184.6 (CO),
140.1, 128.4, 127.4, 125.8 (CPh), 136.8 (CH2ꢁC
6 H),
1H-NMR (400 MHz, CDCl3) l: 7.29–7.21 (m, 5H,
118.1 (CH2ꢁCH), 57.5 (Ph–CH), 47.0 (C–COOH),
6
6
Ph), 6.05 (m, 1H, CH2ꢁCH
CH2ꢁCH), 3.80 (m, 1H, Ph–CH
Hz, J=5 Hz, CH
6
) 5.20–4.95 (m, 2H,
), 2.77 (dd, 1H, J=12
23.5, 22.0 (CH3). HMRS Calc. for C13H16O2, 204.1229.
Found, 204.1230.
6
6
6
–tBu), 1.04 (s, 9H, CH3).
4.11. 2-Methyl-2-(2-phenyl-cyclopropyl)propionic acid
(m.p. 48°C)
4.7. 2,5-Diphenyl-pent-4-enoic acid [39]
1H-NMR (200 MHz, CDCl3) l: 7.36–7.03 (m, 10H,
Ph), 6.35 (d, 1H, J=16 Hz, Ph–CH), 6.03 (m, 1H,
1H-NMR (400 MHz, CDCl3) l: 7.26–7.11 (m, 5H,
Ph), 1.92 (dt, J=8.86, 5.42, 5.42, 1H, Ph–CH), 1.41
(dt, J=9.36, 5.90, 5.90, CH–C(Me2)), 1.19 (s, 3H,
CH3), 1.17 (s, 3H, CH3), 1.02 (dt, J=8.86, 5.41, 5.43,
Ph–CHꢁCH
CH2), 2.60 (m, 1H, CH2
CDCl3) l: 179.6 (CO), 138.5, 136.6 (CPh), 128.9–126.3
(CPh+Ph–CHꢁCH), 132.5 (Ph–CH), 51.8 (C
COOH), 36.6 (CH2).
6
), 3.63 (t, 1H, J=8 Hz, CH
6 ), 2.89 (m, 1H,
6
6
), 1.3. 13C-NMR (100 MHz,
1H, Ph–CH–CH2
Ph–CH–CH2
). 13C-NMR (100 MHz, CDCl3) l: 183.0
(CO), 142.0, 127.0, 125.0, 124.5 (CPh), 40.5 (C
COOH), 29.7 (Ph–CH), 22.0 (CH3), 21.5 (CH3), 18.0
(CH–C(Me2)), 10.5 (CH2). HMRS Calc. for C13H16O2,
6 ), 0.89 (dt, J=8.86, 5.41, 5.44, 1H,
6
6
6 –
6
6
–
6
4.8. 2,3-Diphenyl-pent-4-enoic acid [40]
4.8.1. h Diastereoisomer
6
204.1229. Found, 204.1226.
1H-NMR (400 MHz, CDCl3) l: 7.36–7.00 (m, 10H,
Ph), 5.62 (ddd, 1H, J=17.2 Hz, J=10.2 Hz, J=7.2
4.12. 2,2-Cyclohexyl-5-phenyl-pent-4-enoic acid
Hz, CH2ꢁCH
CHHꢁCH), 4.67 (dd, 1H, J=17.2 Hz, J=1.2 Hz,
CHHꢁCH), 3.91 (m, 2H, Ph–CH
). 13C-NMR (100
6 ), 4.77 (dd, 1H, J=10.2 Hz, J=1.2 Hz,
6
1H-NMR (400 MHz, CDCl3) l: 7.37–7.21 (m, 5H,
Ph), 6.44 (d, 1H, J=15.2 Hz, Ph–CHꢁ), 6.19 (dt, 1H,
6
6

H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
195
J=15.2 Hz, J=7.6 Hz, Ph–CHꢁCH
6
), 2.47 (d, 2H,
(CO), 140.2, 139.1 (CPh), 137.1, 135.6 (CHꢁ), 128.7–
127.2 (CPh), 118.2, 117.4 (CH2ꢁ), 84.4, 84.3 (C
COOH), 59.4, 59.3 (Ph–CH), 52.9, 52.6 (Me–O). These
acid were converted into the lactone which were charac-
terized further.
J=7.6 Hz, CH2), 1.65–1.58 (m, 4H, CH2), 1.50–1.25
(m, 6H, CH2). 13C-NMR (100 MHz, CDCl3) l: 183.4
(CO), 133.2, 128.6, 127.3, 126.3 (CPh), 137.5, 125.2
6 –
6
(CHꢁ), 47.7 (C6 –COOH), 43.5 (CH2), 33.6, 25.8, 23.2
(CH2). HMRS Calc. for C16H20O2, 244.1463. Found,
244.1461.
4.18. 2-Phenoxy-5-phenyl-pent-4-enoic acid
4.13. 2,2-Cyclohexyl-3-phenyl-pent-4-enoic acid
1H-NMR (200 MHz, CDCl3) l: 7.38–7.21(m, 7H,
Ph), 7.04–6.89 (m, 3H, Ph), 6.55 (d, 1H, J=15.8 Hz,
Ph–CH), 6.28 (dt, 1H, J=15.7 Hz, J=6.9 Hz, Ph–
1H-NMR (400 MHz, CDCl3) l: 7.27–7.20 (m, 5H,
Ph), 6.30 (m, 1H, CH2ꢁCH6 ), 5.14 (m, 2H, CH6 2ꢁCH),
CHꢁCH6 ), 4.78 (dd, 1H, J=6.4 Hz, J=5.9 Hz, CH6 –
3.43 (d, 1H, J=10.4 Hz, Ph–CH), 1.65–1.58 (m, 4H,
CH2), 1.50–1.25 (m, 6H, CH2). 13C-NMR (100 MHz,
CDCl3) l: 182.5 (CO), 136.7, 133.2–125.2 (CPh), 140.1
COOH), 2.89 (dd, J=6.6 Hz, J=5.9 Hz, 2H, CH2).
13C-NMR (50 MHz, CDCl3) l: 176.7 (CO), 157.4,
136.9 (CPh), 134.0 (Ph–C
128.6, 127.6, 126.4 (CPh), 123.4 (Ph–CHꢁC
(C–COOH), 36.3 (CH2). This acid has been converted
6
H), 129.8, 122.1, 114.7 (CPh),
(CH2ꢁC6 H), 117.6 (C6 H2ꢁCH), 59.6 (Ph–CH), 52.1 (C6 –
COOH), 32.6–23.1 (CH2).
6
H), 76.1
6
to the lactone which was characterized.
4.14. Cyclohexyl-(2-phenyl-cyclopropyl) acetic acid
1H-NMR (400 MHz, CDCl3) l: 2.10-0.8 (m, 11H),
1.0–0.40 (m, 4H, CH–(CH2 2
) ). 13C-NMR (100 MHz,
CDCl3) l: 183.2 (CO), 46.2 (C–COOH.), 32.2, 25.9,
23.6 ((CH2)5), 20.9 (CH–(CH2)2–), 0.9 (CH–(CH2)2–).
4.19. 2-Ethyl-pent-4-enoic acid [42]
6
6
1H-NMR (400 MHz, CDCl3) l: 5.78 (dddd, 1H,
J=17.0 Hz, J=10.2 Hz, J=6.6 Hz, J=6.6 Hz,
6
6
HMRS Calc. for C16H20O2, 244.1463. Found, 244.1461.
CH2ꢁCH
CHHꢁCH), 5.04 (dd, 1H, J=10.2 Hz, J=1.0 Hz,
CHH
J=9.1 Hz, CH
CH3), 0.96 (t, 3H, J=7.6 Hz, CH2–CH3
(100 MHz, CDCl3) l: 182.4 (CO), 135.2 (CH2ꢁC
116.9 (CH2ꢁCH), 46.8 (CHCO2H), 35.7 (C
24.6 (CH2CH3), 11.56 (CH2CH3). HMRS Calc. for
6 ), 5.09 (dd, 1H, J=16.8 Hz, J=10.2 Hz,
6
4.15. 2,2,5-Triphenyl-pent-4-enoic acid (m.p. 147°C)
6
ꢁCH), 2.40 (m, 2H, CH2–CHꢁ), 2.27 (d, 1H,
6
–COOH), 1.48–1.73 (m, 2H, CH2
6
–
1H-NMR (400 MHz, CDCl3) l: 7.21–7.06 (m, 15H,
Ph), 6.14 (d, 1H, J=15,8 Hz, Ph–CHꢁ), 5.86 (dt, 1H,
6
). 13C-NMR
6
H),
J=15.8 Hz, J=7.1 Hz, Ph–CHꢁCH
6
), 3.22 (d, 2H,
6
6
6 H2–CHꢁ),
J=7.1 Hz, CH2). 13C-NMR (100 MHz, CDCl3) l:
180.7 (CO), 142.1, 137.0 (CPh), 129.3–125.8 (CPh+
6
6
C7H13O2, 129.0916. Found, 129.0918.
CHꢁ), 60.9 (C6 –COOH), 41.7 (CH2). Anal. Calc. for
C25H15O2: C, 84.14; H, 6.10. Found: C, 84.02; H,
6.23%.
4.20. 2-Cyclopropyl-butanoic acid
1H-NMR (400 MHz, CDCl3) l: 1.48–1.73 (m, 3H,
4.16. 2-Methoxy-5-phenyl-pent-4-enoic acid
CH
CH2–CH3
6
–COOH+CH2
6
–CH3), 0.96 (t, 3H, J=7.6 Hz,
–CH–COOH),
6
), 0.97–1.02 (m, 1H, CH
6
1H-NMR (200 MHz, CDCl3) l: 7.38–7.18 (m, 5H,
Ph), 6.50 (d, 1H, J=15.7 Hz, Ph–CH), 6.23 (dt, 1H,
0.48–0.62 (m, 2H), 0.28–0.34 (m, 1H), 0.14–0.20 (m, 1
H). 13C-NMR (100 MHz, CDCl3) l: 182.4 (CO), 52.3
J=15.7 Hz, J=7.4 Hz, Ph–CHꢁCH6 ), 3.93 (t, 1H,
(C
(CH2C
6
HCO2H), 25.4 (C
6 H2CH3), 13.2 (CH), 11.8
J=6.8 Hz, MeO–CH6 ), 3.45 (s, 3H, Me–O), 2.70 (m,
6
H3), 4.58, 3.31 (CH2)2. HMRS Calc. for
2H, CH2). 13C-NMR (50 MHz, CDCl3) l: 177.2 (CO),
C7H13O2, 129.0916. Found, 129.0918.
137.5 (CPh), 133.2 (Ph–CH), 128.5, 127.3, 126.2 (CPh),
123.9 (Ph–CHꢁC6 H), 79.8 (C6 –COOH), 58.1 (CH3), 36.0
(CH2). This acid has been oxydized directly and the
resulting lactone characterized fully.
4.21. 2-Phenyl-pent-4-enoic acid [42]
1H-NMR (400 MHz, CDCl3) l: 7.23–7.14 (m, 5H,
Ph), 5.62 (ddt, 1H, J=17.3 Hz, J=10.1 Hz, J=9.1
4.17. 2-Methoxy-3-phenyl-pent-4-enoic acid
Hz, CH2ꢁCH
CHHꢁCH), 4.91 (dd, 1H, J=17.3 Hz, J=1.0 Hz,
CHHꢁCH), 3.55 (t, 1H, Ph–CH), 2.43 (m, 2H, CH2).
13C-NMR (100 MHz, CDCl3) l: 178.9 (CO), 136.7,
127.6–126.5 (CPh), 133.8 (CH2ꢁCH), 116.2 (CH2ꢁCH),
50.4 (Ph–CH), 37.0 (CH2).
6 ) 4.98 (dd, 1H, J=10.1 Hz, J=1.0 Hz,
4.17.1. h and i Diastereoisomers
6
1H-NMR (200 MHz, CDCl3) l: 7.35–7.26 (m, 5H,
6
Ph), 6.17 (m, 2H, CH2ꢁCH
(m, 1H, Me–O–CH), 3.81 (m, 1H, Ph–CH), 3.41, 3.40
(s, 3H, Me–O). 13C-NMR (50 MHz, CDCl3) l: 176.4
6 ), 5.18 (m, 2H, CH2ꢁ), 4.07
6
6
6
6

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H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
4.22. 2,2-Dimethyl-pent-4-enoic acid [43]
4.28. 2-Phenoxy-pent-4-enoic acid (m.p. 60°C)
1H-NMR (400 MHz, CDCl3) l: 5.76 (m, 1H,
1H-NMR (400 MHz, CDCl3) l: 7.19–7.16 (m, 2H, H
ortho), 6.91–6.76 (m, 3H, H meta and para), 5.81 (m,
CH2ꢁCH
1.18 (s, 6H, CH3). 13C-NMR (100 MHz, CDCl3) l:
184.4 (CO), 133.9 (CH2ꢁCH), 118.3 (CH2ꢁCH), 44.5
(CH2), 42.2 (C–COOH), 24.6 (CH3).
6 ), 5.07 (m, 2H, CH6 2ꢁCH), 3.67 (m, 2H, CH6 2),
1H, CH2ꢁCH
1H, J=6.1 Hz, J=5.6 Hz, Ph–O–CH
J=6.1 Hz, J=5.6 Hz, CH2). 13C-NMR (100 MHz,
CDCl3) l: 176.4 (CO), 156.3 (CPh), 130.9 (CH2ꢁCH),
128.6, 120.9, 114.1 (CPh), 117.9 (CH2ꢁCH), 74.6 (C
6
–), 5.09 (m, 2H, CH2
6
ꢁCH–), 4.62 (dd,
6
6
6
), 2.64 (dd, 2H,
6
6
6
6 –
4.23. 2-Methyl-2-(cyclopropyl)propionic acid [44]
1H-NMR (400 MHz, CDCl3) l: 1.06 (s, 6H, CH3),
COOH), 35.8 (CH2). Anal. Calc. for C11H12O3: C,
68.75; H, 6.25. Found: C, 68.71; H, 6.30%.
1.18 (m, 1H, CH
13C-NMR (100 MHz, CDCl3) l: 184.8 (CO), 41.1 (C
COOH), 22.6(CH3), 19.4 (CH–(CH2)2), 0.85 (CH–
(CH2)2).
6 –(CH2)2), 0.36 (m, 4H, CH–(CH6 2)2).
4.29. 2-Cyclopropyl-2-phenoxy-acetic acid
6
–
6
1H-NMR (400 MHz, CDCl3) l: 7.19–7.16 (m, 2H, H
ortho), 6.91–6.76 (m, 3H, H meta and para), 3.99 (d,
6
1H, J=7.6 Hz, CH
(CH2)2–CH), 0.62–0.45 (m, 4H, (CH2 2
NMR (100 MHz, CDCl3) l: 176.7 (CO), 156.4, 128.3,
121.2, 114.0 (CPh), 78.0 (C–COOH), 12.5 (CH2)2–
H), 2.7, 1.3 ((CH2)2–CH). HMRS Calc. for C11H12O3,
6
–COOH), 1.35–1.27 (m, 1H,
) –CH). 13C-
4.24. 1-Allyl-cyclohexane carboxylic acid [42]
1H-NMR (400 MHz, CDCl3) l: 5.75 (m, 1H,
6
6
6
CH2ꢁCH), 5.06 (m, 2H, CH2ꢁCH), 2.28 (d, 1H, J=7.4
Hz, CH2), 2.03–1.02 (m, 10H, (CH2)5). 13C-NMR (100
MHz, CDCl3) l: 182.9 (CO), 133.3 (CH2ꢁCH), 111.9
(CH2ꢁCH), 47.2 (C–COOH), 33.5 (CH2ꢁCH–CH2),
28.8, 25.7, 25.4 ((CH2)5).
6
6
C6
6
192.0786. Found, 192.0792.
6
6
6
6
4.30. 2-Methyl-2-phenoxy-pent-4-enoic acid [46]
6
1H-NMR (400 MHz, CDCl3) l: 7.22–7.17 (m, 2H,
Ph ortho), 7.04–6.89 (t, 1H, J=7.2 Hz, Ph meta), 6.88
4.25. 1-Cyclopropyl-cyclohexane carboxylic acid
(d, 2H, J=8 Hz, H para), 5.81 (m, 1H, CH2ꢁCH
(m, 2H, CH2=CH), 2.70 (dd, 1H, J=14.1 Hz, J=7.1
Hz, ꢁCH–CHH), 2.60 (dd, 1H, J=14.1 Hz, J=7.1
Hz, ꢁCH–CH
H), 1.44 (s, 3H, CH3). 13C-NMR (100
MHz, CDCl3) l: 177.9 (CO), 154.4, 129.3, 123.1, 120.2
(CPh), 133.2 (CH2ꢁCH), 119.7 (CH2ꢁCH), 81.7 (C
6 ), 5.10
1H-NMR (400 MHz, CDCl3) l: 2.10–0.8 (m, 11H),
6
0.40 (m, 4H, CH–(CH
2)2). 13C-NMR (100 MHz,
CDCl3) l: 183.2 (CO), 46.2 (C–COOH), 32.2, 25.9,
23.6 ((CH2)5), 20.9 (CH–(CH2)2–), 0.9 (CH–(CH2)2–).
6
6
6
6
6
6
6
6
6
6 –
HMRS Calc. for C10H16O2, 168.1229. Found, 168.1224.
COOH), 43.4 (CH2), 21.3 (CH3). HMRS Calc. for
C12H14O3, 206.0943. Found, 206.0937.
4.26. 2,2-Diphenyl-pent-4-enoic acid (m.p. 142°C) [45]
1H-NMR (400 MHz, CDCl3) l: 7.38–7.28 (m, 10H,
4.31. 2-Cyclopropyl-2-phenoxy-propionic acid
Ph), 6.5 (m, 1H, CH2ꢁCH
3.19 (d, 2H, J=7.0, Hz, CH2). 13C-NMR (100 MHz,
CDCl3) l: 180.2 (CO), 142.0 (CPh), 134.0 (CH2ꢁCH),
H), 60.3 (C–
6 ), 4.98 (m, 2H, CH6 2ꢁCH),
1H-NMR (200 MHz, CDCl3) l: 7.29–6.92 (m, 5H,
Ph), 1.45 (s, 3H, CH3), 1.40 (m, 1H, CH), 0.66 (m, 4H,
2CH2). 13C-NMR (100 MHz, CDCl3) l: 177.9 (CO),
6
129.2–128.0–127.2, (CPh), 118.6 (CH2ꢁC
6
154.4, 129.2, 123.1, 120.6 (CPh), 81.0 (C
(CH3), 21.3 (CH3), 19.6 (–CH((CH2)2), 2.0, 1.6 (–
CH((CH2)2). HMRS Calc. for C12H14O3, 206.0943.
Found, 206.0937.
6 –COOH), 22.0
COOH), 42.6 (CH2).
6
6
4.27. 2-Methoxy-pent-4-enoic acid
1H-NMR (200 MHz, CDCl3) l: 5.68 (dddd, 1H,
J=23.6 Hz, J=13.7 Hz, J=9.8 Hz, J=6.9 Hz,
4.32. 2-Methyl-oct-4-enoic acid (cis and trans)
CH2ꢁCH
1H, J=6.9 Hz, J=5.4 Hz, Me–O–CH
CH3–O), 2.37 (m, 2H, CH2). 13C-NMR (100 MHz,
CDCl3) l: 177.3 (CO), 132.5(CH2ꢁCH–), 118.4
(CH2ꢁCH), 79.7 (C–COOH), 58.2 (CH3–O), 36.8
6
–), 5.04–4.95 (m, 2H, CH2
6
ꢁCH–), 3.75 (dd,
1H-NMR (400 MHz, CDCl3) l: 5.48 (dt, 1H, J=
15.2 Hz, J=7.1 Hz, CHꢁ), 5.36 (dt, 1H, J=15.2 Hz,
6
), 3.29 (s, 3H,
J=7.1 Hz, CHꢁ), 2.50 (m, 1H, CH
2.44 (m, 1H, CHH–CHꢁ), 2.14–2.26 (m, 1H, CHH
CHꢁ), 1.97 (q, 2H, J=7.1 Hz, CH3–CH2–CH2), 1.36
(m, 2H, CH3–CH2), 1.16 (d, 3H, J=7.1 Hz, CH3
CH), 0.90 (t, 3H, J=7,1 Hz, CH3 cis) 0.87 (t, 3H,
6 –COOH), 2.33–
6
6
6 –
6
6
6
(CH2). Anal. Calc. for C6H10O3: C, 55.32; H, 7.68.
Found: C, 55.21; H, 8.13.
6
6 –

H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
197
J=7,1 Hz, CH3 trans). 13C-NMR (50 MHz, CDCl3) l:
CHꢁ), 3.81 (dd, 1H, J=6.4 Hz, J=5.4 Hz, MeO–
CH), 3.41 (MeO), 2.49 (m, 2H, MeO–CH–CH2), 1.96
(m, 2H, CH3–CH2–CH6 2), 1.35 (m, 2H, CH3–CH6 2),
180.1 (CO), 133.0 (ꢁC
6
H trans), 132.3 (ꢁC
6
H cis), 126.4
H2–CHꢁCH
6
6
(ꢁCH trans), 125.8 (ꢁC
6
6
H cis), 36.4 (C
6
trans), 34.6, 30.9, 29.3, 22.7, 22.5 (CH2), 16.24 (C
CH–COOH cis), 16.15 (CH3–CH–COOH trans), 13.7
(CH3 cis), 13.5 (CH3 trans). HMRS Calc. for C9H15O2
6
H3–
0.86 (t, 3H, J=7.2 Hz, CH3). 13C-NMR (50 MHz,
CDCl3) l: 176.9 (CO), 134.1 (CHꢁ trans), 133.5 (CHꢁ
6
cis), 123.4 (ꢁCH trans), 123.1 (ꢁCH cis), 80.1 (C
COOH), 57.8 (OCH3), 35.4 (CH2–CH–OMe trans),
34.3 (CH3–CH2–CH2 cis), 30.5, 29.4 (CH2 cis), 22.7
(CH3–CH2 cis), 22.1 (CH3–CH2 trans),13.8 (CH3 cis),
6 –
(MH), 157.1229. Found, 157.1232.
6
6
6
4.33. 2-Phenyl-oct-4-enoic acid
6
6
13.2 CH3 trans). HMRS Calc. for C9H17O3, (MH)
1H-NMR (200 MHz, CDCl3) l: 7.37–7.31 (m, 5H,
Ph), 5.52 (m, 1H, CHꢁ), 5.34 (m, 1H, CHꢁ), 3.65 (m,
173.1178. Found, 173.1177.
1H, Ph–CH
CHꢁ), 2.51 (m, 1H, Ph–CH–CH
Ph–CH–CHH), 1.96 (m, 2H, CH3–CH2–CH2
(m, 2H, CH3–CH2), 0.86 (t, 3H, J=7,2 Hz, CH3).
13C-NMR (50 MHz, CDCl3) l: 180.3 (CO), 138.2
(CPh), 133.6 (CH(Ph)–CH2–CHꢁ), 128.7, 128.2, 127.6
(CPh), 126.3 (C(Ph2)–CH2–CHꢁCH), 52.2 (Ph–CH),
36.3 (CH(Ph)–CH2–CHꢁCH), 42.5 (C–COOH), 34.7
(CH3–CH2–CH2), 22.6 (CH3–CH2),13.6 (CH3).
6
), 2.21 (d, 2H, J=5.6 Hz, C(Me2)–CH2
H), 2.81 (m, 1H,
), 1.34
6 –
4.37. 2-Methyl-2-phenoxy-oct-4-enoic acid
6
6
6
1H-NMR (200 MHz, CDCl3) l: 7.17–7.14 (m, 2 H,
H meta), 6.93 (t, 1H, J=7.2 Hz, H para), 6.84 (dd, 2H,
J=8,6 Hz, J=1 Hz, H ortho), 5.44 (m, 2H, CHꢁ), 2.57
6
6
(m, 2H, CH2
CH2), 1.40 (s, 3H, CH3
CH3–CH2
), 0.79 (t, 3H, J=7,2 Hz, CH3). 13C-NMR
(50 MHz, CDCl3) l: 179.8 (CO), 155.2 (CPh), 136.3
(C(PhO)–CH2–CHꢁ), 129.6, 123.2, 120.6 (CPh), 120.5
(C(PhO)–CH2–CHꢁCH), 82.3 (C–COOH), 43.0 (CH(-
PhO)–CH2), 35.1 (CH3–CH2–CH2), 22.8 (CH3–CH2),
21.5 (CH3–C–COOH), 14.0 (CH3). Anal. Calc. for
6
–C–COOH), 1.91 (m, 2H, CH3–CH2–
6
6
6
6
–C–COOH), 1.35 (m, 2H,
6
6
6
6
6
HMRS Calc. for C14H18O2, 219.1385. Found, 219.1379.
4.34. 2,2-Dimethyl-oct-4-enoic acid (cis and trans)
1H-NMR (200 MHz, CDCl3) l: 5.49–5.27 (m, 2H,
6
6
6
6
6
6
6
C15H20O3: C, 72.55; H, 8.12. Found: C, 72.64; H,
8.30%.
CHꢁ), 2.31 (d, 2H, J=7.1 Hz, CH
2.24 (d, 2H, J=7.1 Hz, CH2–CH–COOH trans), 2.01
(m, 2H, CH3–CH2–CH2), 1.38 (m, 2H, CH3–CH2),
1.21 (s, 6H, CH3 cis), 1.19 (s, 6H, CH3 trans), 0.91 (t,
3H, J=7,1 Hz, CH3–CH2 cis) 0.89 (t, 3H, J=7,1 Hz,
CH3
–CH2 trans). 13C-NMR (50 MHz, CDCl3) l: 184.8
(CO), 134.5 (CHꢁ trans), 132.9 (CHꢁ cis), 125.2 (ꢁCH
trans), 125.5 (ꢁCH cis), 43.3 (C(Me2)–CH2–CH trans),
42.5 (C–COOH), 37.5 (C(Me2)–CH2–CH cis), 34.7
(CH3–CH2–CH2 trans), 29.4 (CH3–CH2–CH2 cis),
24.5 ((Me)2), 22.8 (CH3–CH2 cis), 22.6 (CH3–CH2
6 2–CH–COOH cis),
6
6
6
4.38. 2-Phenoxy-oct-4-enoic acid (m.p. 43°C) (NMR
for trans)
6
6
1H-NMR (200 MHz, CDCl3) l: 7.22 (t, 2 H, J=8.4
Hz, H meta), 6.93 (t, 1H, J=7.4 Hz, H para), 6.85 (d,
2H, J=8,2 Hz, H ortho), 5.38-5.63 (m, 2H, CHꢁ) 4.62
6
6
6
6
6
(t, 2H, J=6.6 Hz, CH
Hz, CH2–C–COOH), 1.93 (m, 2H, CH3–CH2–CH2
1.37 (m, 2H, CH3–CH2), 0.82 (t, 3H, J=7,1 Hz, CH3).
13C-NMR (50 MHz, CDCl3) l: 177.3 (CO), 157.6
(CPh), 135.2 (CHꢁ), 127.9, 123.4, 121.9, 115.3 (CPh+
ꢁCH), 76.4 (C–COOH), 36.0 (COOH–CH–CH2), 22.8
(CH3–CH2), 13.7 (CH3). Anal. Calc. for C14H18O3: C,
6
–COOH), 2.62 (t, 2H, J=6.0
6
6
6
6
),
trans), 13.8 (CH3 cis), 13.6 (CH3 trans). HMRS Calc.
6
for C10H18O2, 170.1385. Found, 170.1385.
6
4.35. 2,2-Diphenyl-oct-4-enoic acid (m.p. 94°C)
6
6
6
6
1H-NMR (400 MHz, CDCl3) l: 7.38–7.32 (m, 10H,
Ph), 5.43–5.28 (m, 2H, CHꢁ), 3.19 (d, 2H, J=5.6 Hz,
71.79; H, 7.69. Found: C, 71.68; H, 7.83%.
C(Ph2)–CH6 2), 1.89 (m, 2H, CH3–CH2–CH6 2), 1.29 (m,
2H, CH3–CH2), 0.84 (t, 3H, J=7,4 Hz, CH3). 13C-
NMR (100 MHz, CDCl3) l: 181.0 (CO), 142,4 (CPh),
135.1 (C(Ph2)–CH2–CHꢁ), 129.4, 128.9, 128.0 (CPh),
125.2 (Pr–CHꢁ), 60.8 (C–COOH), 41.6 (C(Ph2)–CH2),
34.9 (CH3–CH2–CH2), 22.6 (CH3–CH2),13.7 (CH3).
HMRS Calc. for C20H22O2, (MH) 294.1698. Found,
294.1703.
4.39. 3,5-Diphenyl-2-methyl-pent-4-enoic acid
4.39.1. h Diastereoisomer (m.p. 128°C)
1H-NMR (400 MHz, CDCl3) l: 7.20–7.37 (m, 10 H,
Ph), 6.49 (d, 1H, J=15.8 Hz, Ph–CH
J=15.8 Hz, J=7.6 Hz, Ph–CHꢁCH), 3.65 (t, 1H, J=
9.6 Hz, PhCH), 2.95 (m, 1H, CH–COOH), 1.06 (d, 3H,
J=6.6 Hz, CH3). 13C-NMR (50 MHz, CDCl3) l: 182.0
6 ꢁ), 6.42 (dd, 1H,
6
6
6
4.36. 2-Methoxy-oct-4-enoic acid [47]
(CO), 141.2 (CPh), 137.3 (C
6
Hꢁ), 131.1–126.4 (CPh+
1H-NMR (200 MHz, CDCl3) l: 5.60–5.27 (m, 2H,
ꢁCH), 52.6 (CHPh), 45.5 (C
6
6
6
–COOH), 16.0 (CH3).

198
H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
4.39.2. i Diastereoisomer (m.p. 111°C)
4.44. Typical experimental procedure for the
H2O2/MTO reactions
1H-NMR (400 MHz, CDCl3) l: 7.18–7.35 (m, 10 H,
Ph), 6.47 (d, 1H, J=15.8 Hz, Ph–CH
J=15.8 Hz, J=9.3 Hz, Ph–CHꢁCH
J=9.3 Hz, PhCH), 2.86–2.95 (m, 1H, CH
1.25 (d, 3H, J=7.4 Hz, CH3). 13C-NMR (50 MHz,
CDCl3) l: 181.8 (CO), 142.4 (CPh), 137.4 (CHꢁ),
132.4–126.7 (CPh+ꢁCH), 52.7 (CHPh), 45.4 (C
6
ꢁ), 6.24 (dd, 1H,
), 3.65 (t, 1H,
–COOH),
6
The unsaturated acid (1–3 mmol), 31% H2O2 (1,1
equivalents) and chloroform (2–5 ml) were placed in a
25 ml flask. MTO (5 mol%) was added and the mixture
stirred vigorously at room temperature until the disap-
pearance of the olefinic protons (1H-NMR). Any re-
maining MTO and/or H2O2 were decomposed with the
addition of dilute thiosulphite solution. The organic
layer was removed and the aqueous layer was extracted
with dichloromethane. The combined organic layers
were dried (MgSO4) and the products purified by
column chromatography. Cyclopropane acids were re-
covered by acidification of the aqueous layer followed
by extraction with dichloromethane.
6
6
6
6
6
6 –
COOH), 16.0 (CH3). HMRS Calc. for C18H19O2, (MH)
266.1307. Found, 266.1306.
4.40. 3,5-Diphenyl-2,2-dimethyl-pent-4-enoic acid (m.p.
85°C)
1H-NMR (400 MHz, CDCl3) l: 7.52–7.32 (m, 10 H,
Ph), 6.63 (d, 1H, J=15.8 Hz, Ph–CH
J=15.8 Hz, J=10.0 Hz, Ph–CHꢁCH
J=8.0 Hz, CH–COOH), 1.37 (s, 3H, CH3), 1.32 (s,
3H, CH3). 13C-NMR (50 MHz, CDCl3) l: 184.2 (CO),
140.4 (CPh), 137.5 (CHꢁ), 133.2–126.6 (CPh+ꢁCH),
52.8 (CHPh), 47.3 (C–COOH), 23.5 (CH3), 22.6 (CH3).
6
ꢁ), 6.49 (dd, 1H,
6
), 3.93 (d, 1H,
6
4.45. 2-Methyl-2-(3-phenyl-oxiran-2-yl)-propionic acid
1H-NMR (400 MHz, CDCl3) l: 7.30–7.22 (m, 5H,
6
6
6
6
Ph), 4.93 (d, 1H, J=8.6 Hz, Ph–CH
Ph–CH–CH), 1.95 (d, 2H, J=13.2 Hz, CH2
C(Me3)2), 1.33 (s, 6H, CH3
CDCl3) l: 175 (CO), 131–125 (CPh), 85.0 (Ph–C
66.5 (Ph–CH–CH), 41.2 (C
27.5 (CH3)
6
), 3.95 (m, 1H,
Anal. Calc. for C19H20O2: C, 81.40; H, 7.19. Found: C,
81.24; H, 7.12%.
6
6
–
6
). RMN: 13C (100 MHz,
6
H),
4.41. 2-Isopropyl-5-phenyl-pent-4-enoic acid
6
6 –COOH), 28.6 (CH2), 27.9,
1H-NMR (200 MHz, CDCl3) l: 7.35–7.20 (m, 5 H,
Ph), 6.5 (d, 1H, J=16 Hz, Ph–CH
J=16 Hz, J=8 Hz, Ph–CHꢁCH), 4.98 (s, 2H, CH2
3.24 (t, 1H, J=8 Hz, CH2ꢁCH), 2.85–2.40 (m, 2H,
CH2), 12O2.80 (s, 3H, CH3). 13C-NMR (50 MHz,
CDCl3) l: 179.2 (CO), 141.4 (CPh), 137.5 (CHꢁ),
–COOH),
6
ꢁ), 6.15 (dt, 1H,
4.46. 5-(Hydroxy-phenyl-methyl)-3,3-
dimethyl-dihydrofuran-2-one (m.p. 52°C)
6
6
ꢁ),
6
1H-NMR (400 MHz, CDCl3) l: 7.38–7.29 (m, 5H,
6
Ph), 5.13 (d, 1H, J=3 Hz, Ph–CH
6
), 4.60 (m, 1H,
), 1.21
132.2–126.2 (CPh), 114.9 (ꢁCH2), 53.0 (C
6
CH–O), 1.67 (dd, 1H, J=13 Hz, J=6 Hz, CH2
6
6
33.0 (CH2), 20.5 (CH3).
(dd, 1H, J=13 Hz, J=10 Hz, CH6 2), 1.26 (s, 3H, CH3),
1.20 (s, 3H, CH3). 13C-NMR (100 MHz, CDCl3) l:
4.42. 5-Phenyl-pent-4-enoic acid
182.3 (CO), 138, 127.5, 127.2, 125.0 (CPh), 78.7 (Ph–
C6 H), 71.3 (CH–O), 39.2 (C6 –COO), 34.5 (CH2), 23.9,
1H-NMR (200 MHz, CDCl3) l: 7.55–7.15 (m, 5 H,
Ph), 6.45 (d, 1H, J=16 Hz, Ph–CHꢁ), 6.20 (dt, 1H,
J=16 Hz, J=8 Hz, Ph–CHꢁCH), 2.55 (m, 4H, CH2).
13C-NMR (50 MHz, CDCl3) l: 179.6 (CO), 147.2
(CPh), 142.0 (CHꢁ), 138–120.2 (CPh+ꢁCH), 33.9
(C H2–COOH). HMRS Calc. for
23.7 (CH3). Anal. Calc. for C13H16O3: C, 70.91; H, 7.27.
Found: C, 70.71; H, 7.31%.
6
6
4.47. 5-(Hydroxy-methyl)-3,3-dimethyl-4-
phenyl-dihydrofuran-2-one (m.p. 51°C)
6
6
6
H2–CHꢁ), 27.9 (C6
C11H12O2, 176.0837. Found, 176.0843.
4.47.1. h Diastereoisomer
1H-NMR (400 MHz, CDCl3) l: 7.25–6.96 (m, 5H,
Ph), 4.90 (m, 1H, CH–O), 3.61 (dd, 1H, J=12.7 Hz,
4.43. Mixture of
5-phenyl-2-trimethylsilanyl-pent-4-enoic (A) acid and
3-phenyl-2-trimethylsilanyl-pent-4-enoic acid (B)
J=8.1 Hz, CH
J=4.8 Hz, CHH
CH
), 1.42 (s, 3H, CH3), 0.88 (s, 3H,CH3). 13C-NMR
(100 MHz, CDCl3) l: 182.0 (CO), 135.0–128.0 (CPh),
81.1 (Ph–CH), 63.4 (CH2), 55.8 (CH–O), 45.2 (C
6
H–OH), 3.55 (dd, 1H, J=12.7 Hz,
6
–O), 3.18 (d, 1H, J=5.6 Hz, Ph–
6
1H-NMR (200 MHz, CDCl3) l: 7.40–7.15 (m, Ph),
6.40 (d, J=16 Hz, Ph–CH
J=8 Hz, Ph–CHꢁCH, A), 6.15–5.75 (m, CHꢁ, B),
5.24–4.90 (m, ꢁCH2, B), 3.85–3.7 (m, Ph–CH, B),
2.75–2.55 (m, CH2, A and B), 2.35–2.15 CH2–CH
6
ꢁ, A), 6.20 (dt, J=16 Hz,
6
6 –
6
COO), 26.1, 20.6 (CH3).
6
6
–
4.47.2. i Diastereoisomer
COOH, A), 0.15 (s, Si–CH3). HMRS Calc. for
C14H20O2Si, 248.1233. Found, 248.1228.
1H-NMR (400 MHz, CDCl3) l: 7.25–6.96 (m, 5H,
Ph), 4.90 (ddd, 1H, J=11.2 Hz, J=4.6 Hz, J=2.5 Hz,

H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
199
CH–O), 3.87 (dd, 1H, J=12.7 Hz, J=2.5 Hz, CH
O), 3.31 (dd, 1H, J=12.2 Hz, J=4.1 Hz, CHH–O),
3.28 (d, 1H, J=11.2 Hz, Ph–CH), 1.21 (s, 3H, CH3),
0.88 (s, 3H, CH3). 13C-NMR (100 MHz, CDCl3) l:
181.0 (CO), 136.0–128.0 (CPh), 80.6 (Ph–CH), 62.4
(CH2), 53.0 (CH–O), 44.9 (C–COO), 23.8, 21.0 (CH3).
6
H–
(m, 10H, ((CH2)5). 13C-NMR (100 MHz, CDCl3) l:
181.9 (CO), 138.5, 128.6, 128.1, 126.1 (CPh), 80.3
(CH–O), 72.4 (HO–CH), 44.8 (Cq), 33.7, 32.2, 31.5,
25.3, 22.1, 22.0 (CH2). Anal. Calc. for C16H20O3: C,
73.84; H, 7.69. Found: C, 73.75; H, 7.85%.
6
6
6
6
Anal. calc. for C13H16O3: C, 70.91; H, 7.27. Found: C,
70.81; H, 7.49%.
4.52. 3-Tertiobutyl-5-(hydroxy-phenyl-methyl)-
dihydrofuran-2-one (m.p. 86°C)
4.48. 5-(Hydroxy-methyl)-3,3-diphenyl-
dihydrofuran-2-one (m.p. 72°C) [48]
4.52.1. h Diastereoisomer
1H-NMR (400 MHz, CDCl3) l: 7.41–7.32 (m, 5H,
Ph), 5.12 (d, 1H, J=3.6 Hz, Ph–CH), 4.48 (m, 1H,
1H-NMR (400 MHz, CDCl3) l: 7.24–7.09 (m, 10H,
Ph), 4.29 (m, 1H, CH–O), 3.77 (dd, 1H, J=12.7 Hz,
CH–O), 2.44 (dd, 1H, J=12.7 Hz, J=8.6 Hz, CH6 –
C(CH3)3), 2.22 (ddd, 1H, J=12.7 Hz, J=12.7, J=
10.7 Hz, CH2), 1.89–1.80 (m, 1H, CH2), 1.04 (s, 9H,
CH3). 13C-NMR (100 MHz, CDCl3) l: 177.6 (CO),
J=2.5 Hz, HOCH
Hz, J=1.5 Hz,, HOCHH
NMR (100 MHz, CDCl3) l: 178.1 (CO), 142.3, 140.2,
129.4, 128.8, 128.2, 127.8, 127.7 (CPh), 78.2 (Ph2–C),
63.2 (C(OH)H2–CH–O), 57.0 (CH2OH), 38.7 (CH2–
CPh2).
6
H), 3.51 (ddd, 1H, J=12.7, J=3.6
6
), 2.76 (m, 2H, CH2). 13C-
138.8, 130.0–126.4 (CPh), 80.5 (Ph–C
O), 50.7 (CH–C(CH3)3), 32.3 (C(CH3)3), 27.6 (CH3),
24.3 (CH2).
6 H), 72.6 (CH–
6
6
6
6
6
6
4.52.2. i Diastereoisomer
4.49. 5-(Hydroxy-phenyl-methyl)-3,3-
diphenyl-dihydrofuran-2-one (m.p. 66°C)
1H-NMR (400 MHz, CDCl3) l: 7.41–7.32 (m, 5H,
Ph), 5.10 (d, 1H, J=3.1 Hz, Ph–CH), 4.62 (m, 1H,
CH–O), 2.55 (dd, 1H, J=10.7 Hz, J=7.9 Hz, (CH6 –
1H-NMR (400 MHz, CDCl3) l: 7.28–7.19 (m, 15H,
Ph), 5.05 (d, 1H, J=3.5 Hz, Ph–CH), 4.42 (ddd, 1H,
J=3.5 Hz, J=5.1 Hz, J=10.7 Hz, CH–O), 3.02 (dd,
1H, J=13.2 Hz, J=10.7 Hz, CH2), 2.52 (dd, 1H,
J=12.7 Hz, J=5.1 Hz, CH2). 13C-NMR (100 MHz,
CDCl3) l: 176.1 (CO), 141.0, 138.4, 137.2, 131.0–125.1
(CPh), 78.9 (Ph2–C6 H), 71.1 (CH–O), 57.0 (Ph–C6 –
OH), 35.2 (CH2). HMRS Calc. for C23H20O2, 344.1491.
Found, 344.1498.
C(CH3)3), 2.31 (ddd, 1H, J=13.2 Hz, J=10.2, J=4.6
Hz, CH2), 1.89–1.80 (m, 1H, CH2), 1.02 (s, 9H, CH3).
13C-NMR (100 MHz, CDCl3) l: 179.1 (CO), 139.4,
130.0–126.4 (CPh), 81.3 (Ph–CH), 74 (CH–O), 50.0
(CH–C(CH3)3), 33.3 (C(CH3)3), 27.6 (CH3), 24.0
(CH2). HMRS Calc. for C15H2OO3, 248.1491. Found,
248.1486.
4.53. 5-Hydroxymethyl-3-phenoxy-dihydro-furan-2-one
4.50. 5-Hydroxymethyl-2-oxa-spiro[4.5]decan-1-one
(m.p. 112°C)
4.53.1. h Diastereoisomer
1H-NMR (400 MHz, CDCl3) l: 7.37–7.32 (m, 5H,
Ph), 5.14 (d, 1H, J=2.5 Hz, Ph–CH
J=8.1 Hz, J=4.1 Hz, J=2.5 Hz, CH–O), 4.19 (dd,
1H, J=8.1 Hz, J=6.6 Hz, Me–O–CH), 3.53 (s, 3H,
Me–O), 2.52 (ddd, 1H, J=13.2 Hz, J=8.1 Hz, J=4.1
Hz, CHH), 1,91 (ddd, 1H, J=13.2 Hz, J=8.1 Hz,
J=6.6 Hz, CH
H). 13C-NMR (100 MHz, CDCl3) l:
175.4 (CO), 138.8, 128.8, 128.2, 126.0 (CPh), 81.3 (Ph–
H), 75.6 (CH–O), (73.2 (Me–O–CH), 58.3 (Me–O),
28.7 (CH2).
6 ), 4.76 (ddd, 1H,
1H-NMR (400 MHz, CDCl3) l: 4.54 (m, 1H, CH–
O), 3.89 (dd, 1H, J=12.7 Hz, J=3.0 Hz, (HO)CH2
3.61 (dd, 1H, J=12.7 Hz, J=5.1 Hz, (HO)CH2), 2.24
(dd, 1H, J=6.6 Hz, J=12.7 Hz, CH2–CH–O), 1.89
(dd, 1H, J=9.6 Hz, J=12.7 Hz, CH2–CH–O), 1.81–
6
),
6
6
6
6
6
6
1.71 (m, 3H, CH2), 1.64–1.52 (m, 4H, CH2), 1,.0–1.24
(m, 3H, CH2). 13C-NMR (100 MHz, CDCl3) l: 182.0
(CO), 77.8 CH–O), 63.9 (HO)CH2), 44.9 (Cq), 34.1,
C6
6
6
33.9, 32.1, 25.3, 22.2, 22.1 (C6 H2). HMRS Calc. for
C10H16O3, 184.1178. Found, 184.1173.
4.53.2. i Diastereoisomer
1H-NMR (400 MHz, CDCl3) l: 7.40-7.28 (m, 5H,
Ph), 5.10 (d, 1H, J=3.5 Hz, Ph–CH), 4.74 (ddd, 1H,
J=7.1 Hz, J=5.1 Hz, J=3.5 Hz, CH–O), 3.92 (dd,
1H, J=7.1 Hz, J=6.1 Hz, Me–O–CH), 3.46 (s, 3H,
Me–O), 2.35 (ddd, 1H, J=13.5 Hz, J=7.5 Hz, J=5.1
Hz, CHH), 2.08 (ddd, 1H, J=13.5 Hz, J=7.5 Hz,
J=6.1 Hz, CH
H). 13C-NMR (100 MHz, CDCl3) l:
173.5 (CO), 137.5, 127.7, 126.0, 125.8 (CPh), 80.0
(HO–CH(Ph)), 74.8 (HO–CH–CH–O), 74.3(Me–O–
4.51. 3-(Hydroxy-phenyl-methyl)-2-oxa-
spiro[4.5]decan-1-one
6
6
1H-NMR (400 MHz, CDCl3) l: 7.38–7.25 (m, 5H,
Ph), 5.11 (d, 1H, J=3.4 Hz, (HO)CH
J=12.3 Hz, J=9.6 Hz, J=3.4 Hz, CH–O), 2.08 (dd,
6
), 4.58 (ddd, 1H,
6
6
1H, J=12.8 Hz, J=9.4 Hz, CH2
6
–CH–O), 1.84 (dd,
–CH–O), 1.75–1.18
1H, J=12.7 Hz, J=12.3 Hz, CH2
6
6
6

200
H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
C
6
H), 57.2 (Me–O), 30.7 (CH2). HMRS Calc. for
(CO), 154.2, 129.6, 123.7, 121.0 (CPh), 80.4 (Ph–O–C),
77.6 (CH–O), 63.3 (HO–CH2), 34.9 (CH2–C–Me),
22.8 (Me). HMRS calc. for C12H14O3, 222.0970. Found,
222.0967.
C12H15O4, 223.0970. Found, 223.0964.
6
4.54. 5-Hydroxymethyl-3-phenoxy-dihydro-furan-2-one
4.54.1. h Diastereoisomer
4.56. 5-(Hydroxy-propyl-methyl)-3,3-
diphenyl-dihydrofuran-2-one
1H-NMR (400 MHz, CDCl3) l: 7.30–7.28 (m, 2H, H
ortho), 7.06–7.01 (m, 3H, H meta and para), 5.09 (t,
1H, J=9.7 Hz, Ph–O–CH), 4.61 (m, 1H, CH–O), 3.94
4.56.1. h and i Diastereoisomers (1/1)
(dd, 1H, J=12.7 Hz, J=2.5 Hz, HO–CH
1H, J=12.7 Hz, J=5.1 Hz, HO–CHH), 2.74 (m, 1H,
CHH–CH(O–Ph)), 2.31 (dt, 1H, J=12.7 Hz, J=9,7
Hz, CHH
–CH(O–Ph)). 13C-NMR (100 MHz, CDCl3)
6
H), 3.71 (dd,
1H-NMR (400 MHz, CDCl3) l: 7.31–7.25 (m, 5H,
Ph), 4.53 (m, CH–O), 4.42 (m, CH–O), 4.16 (m, Ph–
6
6
CH
OH), 2.78 (ddd, J=13.2 Hz, J=10.1 Hz, J=4.5 Hz,
CHH–C(Ph)), 2.54–2.48 (m, CHH–C(Ph), 2.30 (dt,
J=12.7 Hz, J=8.1 Hz, CHH–C(Ph)), 1.59–1.33 (m,
CH3–CH2–CH2
–), 0.97–0.92 (m, CH3). 13C-NMR
6 –), 3.99 (m, CH6 –OH), 3.88 (m, Ph–CH6 and CH6 –
6
l: 173.8 (CO), 129.8, 122.6, 116.0, 110.8 (CPh), 77.6
(CH–OH), 73.5 (Ph–O–CH), 63.5 (HO–CH2), 30.7
(CH2).
6
6
6
6
(100 MHz, CDCl3) l: 178.6, 177.7 (CO), 138.0, 136.9,
4.54.2. i Diastereoisomer
129.1–127.6 (CPh), 81.5, 81.0 (C–OH), 71.5, 70.1
1H-NMR (400 MHz, CDCl3) l: 7.30–7.28 (m, 2H, H
ortho), 7.06–7.01 (m, 3H, H meta and para), 5.20 (t,
1H, J=7.6 Hz, Ph–O–CH), 4.77 (m, 1H, CH–O), 3.99
(CH2–C
CH2–CH2), 30.8, 30.7 (CH3–C
C(Ph)), 14.1 (CH3–CH2–CH2). Anal. Calc. for
6
H–O), 47.0, 46.3 (Ph–C
6
H), 34.5, 33.9 (CH3–
6
6
H2–CH2),19.0 (C
6
H2–
6
(dd, 1H, J=12.7 Hz, J=2.0 Hz, HO–CH
1H, J=12.7 Hz, J=3.0 Hz, HO–CHH), 2.74 (m, 1H,
CHH–CH(O–Ph)), 2.31 (dt, 1H, J=13.2 Hz, J=7.6
Hz, CHH
–CH(O–Ph)). 13C-NMR (100 MHz, CDCl3)
6
H), 3.66 (dd,
C14H18O3: C, 71.79; H, 7.69. Found: C, 71.32; H, 7.89.
6
6
4.57. 5-(Hydroxy-propyl-methyl)-3,3-
diphenyl-dihydrofuran-2-one (m.p. 106°C)
6
l: 174.6 (CO), 129.8, 122.3, 115.9, 110.7 (CPh), 78.6
(CH–O), 72.9 (Ph–O–CH), 63.8 (HO–CH2), 31.7
(CH2). HMRS calc. for C11H12O3, 208.0736. Found,
208.0734.
1H-NMR (400 MHz, CDCl3) l: 7.14–7.11 (m, 10H,
Ph), 4.16 (dt, 1H, J=11.6 Hz, J=4.5 Hz, CH
6 –OH),
3.88 (m, 1H, CH–O), 2.96 (dd, 1H, J=12.7 Hz, J=
10.7 Hz, CHH
J=5.1 Hz, CH
CH2–CH2
(100 MHz, CDCl3) l: 177.8 (CO), 142.4, 140,2, 129.4–
127.8 (CPh), 79.9 (CH–OH), 70.4 (Ph2–CH2–CH),
58.5 (Ph2–C), 37.1 (CH3–CH2–CH2–), 34.4 (CH3–
H2–CH2–),1 9.3 (CH2–C(Ph2)), 14.4 (CH3–CH2–
6
–C(Ph)2), 2.74 (dd, 1H, J=12.7 Hz,
H–C(Ph)2), 1.49–1.21 (m, 4H, CH3–
4.55. 5-Hydroxymethyl-3-methyl-3-phenoxy-
dihydro-furan-2-one
6
6
6
), 0.82 (t, 3H, J=6.6 Hz, CH3). 13C-NMR
4.55.1. h Diastereoisomer
6
1H-NMR (400 MHz, CDCl3) l: 7.29 (t, 2H, J=7.6
Hz, Ph meta), 7.11 (t, 1H, J=7.6 Hz, Ph para), 7.02 (d,
2H, J=7.6 Hz, Ph ortho), 4.67 (m, 1H, CH–O), 3.92
6
6
C6
6
6
CH2). Anal. Calc. for C20H22O3: C, 77.92; H, 6.49.
Found: C, 77.33; H, 6.86%.
(dd, 1H, J=12.7 Hz, J=5.6 Hz, HO–CH
1H, J=12.7 Hz, J=4.6 Hz, HO–CHH), 2.60 (dd, 1H,
J=13.7 Hz, J=6.1 Hz, CHH–C–Me), 2.23 (dd, 1H,
6 H), 3.60 (dd,
6
6
4.58. Typical experimental procedure for palladium
oxidation
J=13.7 Hz, J=9.2 Hz, CH
6
H–C–Me), 1.57 (d, 3H,
J=2.6 Hz, Me). 13C-NMR (100 MHz, CDCl3) l: 175.8
(CO), 154.3, 129.5, 124.4, 122.0 (CPh), 81.5 (Ph–O–C),
To the unsaturated acid (500 mg) in DMF (10 ml)
was added 25 mg of PdCl2(PPh3)2 and 25 mg of
Cu(OAc)2. This mixture was heated at 90°C under
oxygen. After 24 h the solution was cooled, 30 ml of
Et2O was added and the DMF eliminated by treatment
with hydrochloric acid (2 N). The organic phase was
dried (MgSO4) and the products purified by column
chromatography.
78.4 (CH–O), 62.7 (HO–CH2), 36.7 (C6 H2–C–Me),
21.0 (Me). HMRS calc. for C12H14O3, 222.0970. Found,
222.0967.
4.55.2. i Diastereoisomer
1H-NMR (400 MHz, CDCl3) l: 7.29 (t, 2H, J=7.6
Hz, Ph meta), 7.11 (t, 1H, J=7.6 Hz, Ph para), 7.02 (d,
2H, J=7.6 Hz, Ph ortho), 4.67 (m, 1H, CH–O), 3.92
(dd, 1H, J=12.7 Hz, J=5.6 Hz, HO–CH
1H, J=12.7 Hz, J=4.6 Hz, HO–CHH), 2.60 (dd, 1H,
J=13.7 Hz, J=6.1Hz, CHH–C–Me), 2.23 (dd, 1H,
J=13.7 Hz, J=9.2Hz, CHH–C–Me), 1.62 (d, 3H,
J=4.6 Hz, Me). 13C-NMR (100 MHz, CDCl3) l: 176.6
6
H), 3.60 (dd,
4.59. 5-Methylene-3,3-diphenyl-dihydrofuran-2-one [50]
1H-NMR (200 MHz, CDCl3) l: 7.28–7.42 (m, 10H,
6
6
6
Ph), 4.81 (s, 1H, CHH6 ꢁC), 4.45 (s, 1H, CH6 HꢁC), 3.56
(s, 2H, CH2
6
). 13C-NMR (50 MHz, CDCl3) l: 175.4

H. Rudler et al. / Journal of Organometallic Chemistry 624 (2001) 186–202
201
(CO), 152.8 (ꢁC–O), 140.9, 132.4–127.5 (CPh), 89.5
(CH2ꢁ), 57.3 (C(Ph)2), 41.8 (–CH2–).
4.66. 5-Benzyliden-3,3-dimethyl-dihydro-furan-2-one
6
1H-NMR (200 MHz, CDCl3) l: 7.5–7.2 (m, 5H, Ph),
5.54 (s, 1H, ꢁCH), 2.84 (s, 2H, CH2), 1.34 (s, 3H, CH3).
HMRS Calc. for C13H15O2, 203.1072. Found, 203.1068.
4.60. 5-Methylene-3,3-diphenyl-3H-furan-2-one [51]
1H-NMR (200 MHz, CDCl3) l: 7.28–7.42 (m, 10H,
4.67. 5-Benzyl–3,3-dimethyl-3H-furan-2-one
Ph), 5.73 (s, 1H, ꢁCH6
), 2.1 (s, 3H, CH3). 13C-NMR (50
MHz, CDCl3) l: 177.9 (CO), 151.5 (ꢁC–O), 140.6,
128.8–127.5 (CPh), 109.8 (ꢁCH), 61.7 (C(Ph)2), 14.2
(CH3).
1H-NMR (200 MHz, CDCl3) l: 7.2 (m, 5H, Ph), 5.05
(s, 1H, ꢁCH), 3.59 (s, 2H, CH2), 1.26 (s, 3H, CH3).
HMRS Calc. for C13H15O2, 203.1072. Found, 203.1068.
4.61. 5-Methylene-3,3-dimethyl-dihydrofuran-2-one [49]
5. Supplementary material
1H-NMR (200 MHz, CDCl3) l: 4.73 (s, 1H, CHH
6 ꢁ),
4.30 (s, 1H, CH
6
Hꢁ), 2.66 (s, 2H, –CH2–). 1.28 (s, 6H,
Crystallographic data for the structural analysis have
been deposited with the Cambridge Crystallographic
Data Centre, CCDC nos 156558 and 156557. Copies of
this information may be obtained from The Director,
CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK
(fax: +44-1233-336033; e-mail: deposit@ccdc.cam.ac.
uk or www: http://www.ccdc.cam.ac.uk).
CH3). 13C-NMR (50 MHz, CDCl3) l: 183.0 (CO),
150.2 (ꢁC–O), 89.3 (CH2ꢁ), 44.6 (C(Me)2), 40.8 (–
CH2–), 13.8 (CH3).
4.62. Mixture of 3-methylene-2-oxa-spiro[4.5]decan-
1-one (A) and 3-methyl-2-oxa-spiro[4.5]dec-3-en-1-one
(B)
6. Uncited references
1H-NMR (200 MHz, CDCl3) l: 5.37 (s, ꢁCH, B),
4.67 (s, CHH6 ꢁ, A), 4.27 (s, CH6 Hꢁ, A), 2.70 (s, 2H,
[50,51]
CH2, A), 1.95 (s, CH3, B), 1.70–1.05 (m, CH2). 13C-
NMR (50 MHz, CDCl3) l: 179.7 (CO), 153.9, 151.0
(ꢁC–O), 108.5 (CHꢁ), 88.9 (CH2ꢁ), 44.8 (C(Me)2),
37.19 (CH2–Cꢁ), 33.60, 32.22, 25.10, 24.17, 23.56 (CH2)
MS Calc. for C10H15O2, 167.1067. Found, 167.1072.
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