Optically active cyclopentadienyl and indenyl ligands obtained from lactic acid esters

Article abstract of DOI:10.1016/j.jorganchem.2007.10.010

Asymmetric cyclopentadienes and indenes are easily prepared by nucleophilic attack of LiCp or LiInd on tosylate or triflate of ethyl (S)-(-) lactate. The selectivity of the reaction depends on the nature of the leaving group. This is particularly true in the case of the reaction of LiCp with sulfonates of ethyl (S)-(-) lactate. Indeed, only the monosubstituted cyclopentadiene lactate 2 is obtained from the triflate 6, whereas from the tosylate 1, besides 2 (20%) a 1,3-disubstituted cyclopentadiene lactate 3 is isolated (16.5%). From cyclopentadiene and indene lactate 2 and 7, optically active β-hydroxycyclopentadiene 10 and β-hydroxyindene 11 are obtained by reduction with LiAlH₄. Two rhodium(I) complexes 14 and 15 have been synthesized from (R,S)-2-(cyclopentadienyl)N,N-dimethylpropanamide 12 and (S)-2-(cyclopentadiene)propan-1-ol 10, respectively. The molecular structure of these complexes has been determined. Analytical and preparative chiral HPLC have been used to determine the optical purity of the ligands and to isolate enantiopure cyclopentadienyl complexes from racemic or enantiomerically enriched rhodium(I) complexes.

Full text of DOI:10.1016/j.jorganchem.2007.10.010

Available online at www.sciencedirect.com
Journal of Organometallic Chemistry 693 (2008) 23–32
www.elsevier.com/locate/jorganchem
Optically active cyclopentadienyl and indenyl ligands
obtained from lactic acid esters
a,
a
a
a
Richard La¨ı *, Florence Chanon , Christian Roussel , Martial Sanz ,
a
b
Nicolas Vanthuyne , Jean-Claude Daran
a
Universite´ Paul Ce´zanne, Av. Escadrille Normandie-Nie´men, UMR CNRS 6180, F-13013 Marseille, France
b
Laboratoire de Chimie de Coordination, 205 Route de Narbonne, 31077 Toulouse Cedex 04, France
Received 6 September 2007; received in revised form 5 October 2007; accepted 5 October 2007
Available online 10 October 2007
Abstract
Asymmetric cyclopentadienes and indenes are easily prepared by nucleophilic attack of LiCp or LiInd on tosylate or triflate of ethyl
(S)-(ꢀ) lactate. The selectivity of the reaction depends on the nature of the leaving group. This is particularly true in the case of the reac-
tion of LiCp with sulfonates of ethyl (S)-(ꢀ) lactate. Indeed, only the monosubstituted cyclopentadiene lactate 2 is obtained from the
triflate 6, whereas from the tosylate 1, besides 2 (20%) a 1,3-disubstituted cyclopentadiene lactate 3 is isolated (16.5%). From cyclopenta-
diene and indene lactate 2 and 7, optically active b-hydroxycyclopentadiene 10 and b-hydroxyindene 11 are obtained by reduction with
LiAlH4. Two rhodium(I) complexes 14 and 15 have been synthesized from (R,S)-2-(cyclopentadienyl)N,N-dimethylpropanamide 12 and
(S)-2-(cyclopentadiene)propan-1-ol 10, respectively. The molecular structure of these complexes has been determined. Analytical and
preparative chiral HPLC have been used to determine the optical purity of the ligands and to isolate enantiopure cyclopentadienyl com-
plexes from racemic or enantiomerically enriched rhodium(I) complexes.
ꢀ 2007 Elsevier B.V. All rights reserved.
Keywords: Chiral cyclopentadienyl rhodium(I) complexes; Ethyl (S)-(ꢀ) lactate; Cyclopentadiene and indene lactate; Chirality; Chiral HPLC; X-ray
diffraction
1. Introduction
This method was also successfully applied to (S)-(+)-
naproxene and 2-bromo-butene [7] (Scheme 2).
In addition to the ansa complexes which constitute a
new generation of group IV bent metallocenes suitable as
olefin polymerization catalysts, a resurgence of research
has started rather recently in order to produce new opti-
cally active cyclopentadienyl ligands.
As part of our interest in the synthesis of optically active
cyclopentadienyl ligands, we have recently reported the
preparation of differently substituted chiral cyclopentadi-
enes and indenes [1–4] from various natural products.
From methyl(ꢀ)-pinane-3-carboxylate [1,5], using the
Bercaw’s method [6], we could obtain optically active
cyclopentadienes (Scheme 1).
Optically active cyclopentadienyl ligands, bearing a pen-
dant arm in order to reach bidentate coordination provid-
ing a rigid structure that is suited for transfer of
asymmetry, are of great interest in enantioselective cataly-
sis. For this reason we decided to investigate the behaviour
of a-hydroxyesters such as acid lactic esters.
2. Results and discussion
From ethyl (S)-(ꢀ) lactate, two synthetic routes to opti-
cally active cyclopentadienes can be envisioned as shown in
Scheme 3.
*
Preliminary experiments have shown that, under Ber-
caw’s conditions (route (a)), the reaction between ethyl
Corresponding author. Tel.: +33 4 91 288285.
E-mail address: richard.lai@univ-cezanne.fr (R. La¨ı).
0022-328X/$ - see front matter ꢀ 2007 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2007.10.010

24
R. Laı¨ et al. / Journal of Organometallic Chemistry 693 (2008) 23–32
O
Br
R
R
2
4 Li
+
OH
OEt
R'
RO
R'
CO2Me
Li
-
R
2
Cp
1
R'
a)
b)
R =OTs, OTf
R = H
R
2a R = R' = Me
- H2O
OR
O
2b R = H, R' = Me
2c R = Me, R' = H
R'
OH
H
OEt
R
+ RO-
R'
Scheme 1.
H
- H2O
OR
Me
CO2Me
Br
MeO
H
4
Li
+
2
Me
Scheme 3.
OH
MeO2C
CO2Me
Li
MeO
2
O
O
OH
-H2O
Me
OH
Me
Me
O
O
Me
Me
H
- H2O
MeO
Scheme 2.
H
H
lactate and two equivalents of the lithium derivative of 2-
bromobutene afforded the isomeric dienic alcohols in good
yields. However, the formation of the cyclopentadienes by
dehydration with different dehydration agents did not work
at all, the isomeric tertiary alcohols being recovered
unchanged, together with untractable products.
O
Me
O
Me
Scheme 4.
Ethyl lactate, protected as the phenoxy derivative, affor-
ded a similar result.
The same reactivity was also observed with the dimethyl
ketal-protected tartrate (Scheme 4).
So far, we do not have any definitive explanation for the
failure of the dehydration process. The presence of an oxy-
gen atom in a position with respect to the hydroxyl group
could be at the origin of the observed lack of reactivity.
Indeed, one can assume that the carbocation formed in
the first step of the dehydration process could be stabilized
by the oxygen atom in a position, thus preventing the elec-
trocyclization to occur.
This hypothesis find some support in the reaction of
dimethyl succinate which afforded the corresponding dicy-
clopentadiene in good yields, as described by Brintzinger
[8] (Scheme 5).
The other synthetic route (b), consists in a substitution
reaction of SN2 type of cyclopentadienide anions on sulfo-
nates derivatives of ethyl lactate.

R. Laı¨ et al. / Journal of Organometallic Chemistry 693 (2008) 23–32
25
R1
R2
Li
R1
O
R2
R1
R2
2
Cp-
O
MeO2C
OH
NaH
SO2R
SO2R
OH
CO2Me
Scheme 7.
-H2O
fonate monoesters with cyclopentadienide or indenide
anions produces only the expected monosubstituted prod-
ucts [2,4,10,11]. This is in the particular case of sulfonate
diesters that disubstitution products are very often
observed as the result of a sequential inter- and intramolec-
ular reactions as shown in Scheme 7.
H
H
Scheme 5.
The result of this reaction is mostly the formation of
annulated compounds resulting of thermal sigmatropic
rearrangements of intermediate spiroannulated cyclopent-
adienes [12–14] or indenes [15] intermediates.
It is, of course, possible to synthesize di- and even poly-
substituted cyclopentadienes from monosulfonate esters or
alkyl halides by intermolecular reactions. However, in
these cases, the reaction proceeds by successive steps with
a base necessary for the deprotonation of cyclopentadienes
intermediates [16,17].
This synthetic route has been described in the literature
[9] with different substrates but, to our knowledge, not in
the case of acid lactic esters.
When the tosylate of ethyl (S)-(ꢀ) lactate 1 was reacted
with LiCp, the cyclopentadiene lactate 2 was obtained as a
mixture of two isomers ((S)-ethyl 2-(cyclopenta-1,3-die-
nyl)propanoate and (S)-ethyl 2-(cyclopenta-1,4-dienyl)pro-
panoate), as shown in Scheme 6.
Besides this compound, an other unexpected lactate 1,3-
disubstituted cyclopentadiene 3 (16.5% yield) was also
isolated as a mixture of two isomers diethyl (2S,20S)-2,20-
cyclopenta-1,3-diene-1,3-diyldipropanoate and diethyl
(2S,20S)-2,20-cyclopenta-1,3-diene-1,4-diyldipropanoate.
To our knowledge, this is the second example of such a
behaviour in a substitution reaction between a sulfonate
monoester and a cyclopentadienide anion. Indeed, as we
mentioned elsewhere [3], in the case of glucose-substituted
cyclopentadienes and indenes, generally the reaction of sul-
As we proposed earlier [3], for allose-derived cyclo-
pentadiene and indene, the formation of 3 could be tenta-
tively rationalized by a nucleophilic attack of LiCp on 1
with formation of the monosubstituted cyclopentadiene 2.
Intramolecular complexation of one molecule of LiCp with
the oxygen atom of either the carbonyl or the ethoxy group
of the ester function could occur giving a termolecular
structure 4. The complexation of lithium with the oxygen
of a carbonyl group has been described and can explain
the stereoselectivity of different reactions [18,19].
In the case of lactate esters, the cyclopentadienide
anion would abstract a proton to the already bound
O
OEt
TsO
OEt
O
1
LiCp
Li+
O
O
- LiOTs
+ LiCp
O
O
Cp-
LiCp
+
OEt
TsO
H
H
OEt
OEt
1
+
+ lactateOTs 1
OEt
4
OTs
- CpH
2
O
O
OEt
O
OEt
OEt
OEt
EtO
O
H
Li+
-
EtO
+
EtO
- LiOTs
O
O
O
O
OEt
3
OTs
3
5
Scheme 6.
Scheme 8.

26
R. Laı¨ et al. / Journal of Organometallic Chemistry 693 (2008) 23–32
O
cyclopentadiene to give a lactate-substituted cyclopentadie-
nide 5 which, in turn, could attack the complexed tosylate
lactate affording the disubstituted cyclopentadiene
(Scheme 8).
3
OEt
When the triflate 6 of ethyl lactate was reacted with
LiCp, under the same conditions as those used with the tos-
ylate, the monosubstituted cyclypentadiene 2 was found as
the sole product. In this case the yield of 54% is better than
with the tosylate.
7
+
O
Because of the presence of isomers it is not easy to deter-
mine the optical purity of cyclopentadiene lactate. How-
ever, after deprotonation and formation of transition
metal complexes as a single compound, the optical purity
was determined by chiral HPLC and found to be 90%. A
very similar value was obtained starting either from the tri-
flate 6 or the tosylate lactate 1.
H
O
OEt
1) - H+
2) +H+
LiInd
7
OEt
TfO
6
8
+
6
O
3. Obtention of indene lactate
4
8
15
12
18
O
16
11
17
14
13
7
When the tosylate of ethyl lactate 1 was reacted in THF
at low temperature with lithium indenide, indene lactate 7
((S)-ethyl 2-(1H-inden-3-yl)propanoate) was obtained as a
sole isomer with a yield of 57% and an optical purity mea-
sured by chiral HPLC as S:R 97.5:2.5 (Scheme 9).
Starting from triflate 6 of ethyl lactate, it was observed
that, sometimes besides compound 7, the other possible
isomer 8 ((S)-ethyl 2-(1H-inden-1-yl)propanoate) was
formed with a de of 50%. Thermodynamically less stable
than 7, this compound isomerizes thermally or by deproto-
nation and reprotonation to give 7 with an optical purity of
the same value as that of directly formed 7 (S:R 97.5:2.5)
(Scheme 10).
5
9
H
O
3
19
10
2
O
1
9
Scheme 10.
O
LiAlH4
Et2O
OH
10
OEt
A third compound can be isolated by liquid chromato-
graphy and identified by NMR as a disubstituted indene
9 (diethyl (2S,20S)-2,20-(1H-indene-1,3-diyl)dipropanoate).
In 9 a new stereogenic center is created and, on the ground
H
H
2
O
LiAlH4
Et2O
1
of H and 13C NMR study in different solvents, it is possi-
OEt
OH
11
ble to assume that 9 is formed with a very high
diastereoselectivity.
7
It is worthy to note that the same results are obtained
with the tosylate or the triflate of isopropyl (S)-(ꢀ) lactate
but, in these cases, the yields are slightly higher than with
ethyl (S)-(ꢀ) lactate sulfonates. This could be due to a
higher steric hindrance close to the ester carbonyl group,
decreasing undesired nucleophilic attack on this group.
With LiAlH4, cyclopentadiene and indene lactate 2 and
7 are readily converted into the corresponding alcohols, 10
((S)-2-(cyclopenta-1,3-dienyl)propan-1-ol and (S)-2-(cyclo-
Scheme 11.
penta-1,4-dienyl)propan-1-ol) and 11 ((S)-2-(1H-inden-3-
yl)propan-1-ol) in high yields, as shown in Scheme 11.
The optical purity of 11, formed as a single isomer, is
almost identical as the starting ester, according to chiral
HPLC analysis.
These chiral b-hydroxy cyclopentadienes are isomers of
those obtained by attack of chiral propylene oxide with
sodium cyclopentadienide [20].
O
O
LiInd
4. Syntheses of complexes
OEt
OEt
TsO
Attempts to obtain group IV transition metal complexes
from cyclopentadiene and indene lactate by salt elimination
reactions were unsuccessful.
1
7
Scheme 9.

R. Laı¨ et al. / Journal of Organometallic Chemistry 693 (2008) 23–32
27
O
OEt
H
2
M(NMe2)4
O
O
NMe2
OEt
H
M(NMe2)2
12
+ M(OEt)(NMe)3
OEt
O
Fig. 1. ORTEP view of compound 14.
M = Ti or Zr
+ 2 HNMe2
Scheme 12.
- H+
OH
OH
O
1/2 [RhCl(COD)]2
H
O
- H+
Rh(COD)
NMe2
NMe2
10
15
1/2[RhCl(COD)]2
H
Scheme 14.
Rh(COD)
12
14
instead of the hope-for complexes, we observed almost
quantitatively the transformation of the ester function to
an amide function, as shown in Scheme 12 from cyclo-
pentadiene lactate 2.
A similar result was obtained from indenyl ethyl lactate
7 to give 13 quantitatively:
Scheme 13.
We thought it could be possible to obtain titanium or
zirconium complexes by the well-established amine elimi-
nation route [21]. In the case of cyclopentadiene and indene
ethyl lactate 2 and 7, with either Ti(NMe2)4 or Zr(NMe2)4,
Fig. 2. ORTEP view of compound 15.

28
R. Laı¨ et al. / Journal of Organometallic Chemistry 693 (2008) 23–32
O
system manager, Merck-Lachrom L-7100 pump, Merck-
Lachrom L-7360 oven which may accommodate 12 columns
alimented by a Valco 12 positions valve, Merck-Lachrom
L-7400 UV detector and on-line chiroptical detector: Jasco
OR-1590 polarimeter or Jasco CD-1595 circular dichroism
detector. The sign given by the chiroptical detectors is the
sign of the enantiomer in the solvent used for the analyse
[25]. Retention times Rt in min, retention factors ki ¼
ðRt ꢀ Rt Þ=Rt and enantioselectivity factor a = k2/k1 are
NMe2
13
From racemic 2-(cyclopentadienyl)-N,N-dimethylpro-
panamide 12, a cycloocta-1,5-diene rhodium(I) complex
14 was prepared in the racemic version (see Scheme 13).
The X-ray structure of this complex is shown in Fig. 1.
From the racemic complex 14, it was possible to obtain
both enantiomers in a pure form by preparative chiral
HPLC in a multimilligram scale (see Section 5).
The preparation of an optically active cycloocta-1,5-
diene rhodium(I) complex 15 was achieved from cyclo-
pentadiene alcohol 10 as shown in Scheme 14. The optical
purity of 15 was shown to be S:R 95:5 by chiral HPLC.
It was observed that the X-ray analysis was impossible
to carry out on crystals obtained from the mixture contain-
ing 95% of the major enantiomer. However, preparative
chiral HPLC allowed the obtention of the pure major enan-
tiomer, the crystals of which were suitable for an X-ray
determination.
i
0
0
given. Rt was determined by injection of tri-tertio-butyl
0
benzene. N-hexane and 2-PrOH are HPLC grade from
SDS (Peypin, France), the solvents for chromatography
experiments, are degassed and filtered on Millipore mem-
brane 0.45 lm before use. The semi-preparative separation
were performed with Merck-Hitachi LiChrograph L-6000
pump, Merck-Hitachi L-4000 UV detector and Merck D-
7000 system manager. The chiral stationary phases used
are cellulose tris(3,5-dimethylphenylcarbamate) Chiralcel
OD-H (250 · 4.6 mm) and Chiralcel OD (250 · 10 mm),
amylose tris(3,5-dimethylphenylcarbamate) Chiralpak AD
(250 · 4.6 mm) and (250 · 10 mm), and cellulose tris(4-
methylbenzoate) Chiralcel OJ (250 · 4.6 mm), all available
from Chiral Technologies Europe (Illkirch, France).
The X-ray structure of this complex is shown in Fig. 2.
In compound 15, there are eight molecules in the asym-
metric unit. All eight complexes have the same absolute
configuration and are nearly identical. They are intercon-
nected as shown in Fig. 2 by O–Hꢁ ꢁ ꢁO hydrogen bonds
which links four complexes then forming a pseudo tetramer
structure. The other four complexes form also a tetrameric
structure. Furthermore each tetramer is linked by O–Hꢁ ꢁ ꢁO
hydrogen bonds to symmetry related tetramers building
columns of complexes which develop parallel to the b axis.
From the molecular structure, the S absolute configura-
tion found for the cyclopentadienyl ligand, confirms that
the initial nucleophilic attack on the starting sulfonates 1
and 6 occurs via a SN2 substitution.
5.1. Synthesis of cyclopentadiene lactate ((S)-ethyl
2-(cyclopenta-1,3-dienyl)propanoate and (S)-ethyl
2-(cyclopenta-1,4-dienyl)propanoate) 2 from tosylate of
ethyl (S)-(ꢀ)lactate (ethyl (S)-2-[[(4-methylphenyl)
sulfonyl]oxy]propanoate) 1
A solution of LiCp (5 g, 70 mmol), prepared from
freshly cracked dicyclopentadiene and n-BuLi (2.5 M in
hexane), in 100 ml THF was slowly added over 2 h to
a solution of 19 g (69.8 mmol) of tosylate of ethyl lactate
1 in THF (200 ml) cooled at ꢀ78 ꢁC. The solution was
stirred overnight at room temperature. After evaporation
of THF under vacuum, addition of a saturated aqueous
solution of NaCl extraction of the organic compounds
was made with Et2O (5 · 50 ml). The combined extracts
were dried over MgSO4 and Et2O was eliminated under
vacuum leaving the crude product as an oily brown res-
idue (11.5 g). Purification on a silica gel column, fol-
lowed by distillation under reduced pressure, afforded 2
(2.52 g, 20% yield) and 3 (1.67 g, 16.5% yield). The Rf
of 2 and 3 are 0.58 and 0.23, respectively (hexane/Et2O
80/20).
5. Experimental
General comments. All reactions were carried out under
an atmosphere of argon. The solvents were dried by the
appropriate procedure [22] and distilled under nitrogen
before use. Standard Schlenk techniques and conventional
glass vessels were employed. 1H and 13C NMR spectra were
recorded on Bruker AM-200 and Bruker Avance DRX-500
spectrometers, chemical shifts are referenced to internal sol-
vent resonances and reported relative to TMS. Elemental
analyses were carried out by the Spectropole-Service d’Ana-
5.2. Synthesis of cyclopentadiene lactate ((S)-ethyl
2-(cyclopenta-1,3-dienyl)propanoate and (S)-ethyl
2-(cyclopenta-1,4-dienyl)propanoate) 2 from triflate of
ethyl (S)-(ꢀ) lactate (ethyl (S)-2-[[(trifluoromethyl)
sulfonyl]oxy]propanoate) 6
´
´
´ ˆ
lyse Elementaire-Faculte de St Jerome. Optical rotations
were determined on a Perkin–Elmer Model 241 MC digital
polarimeter operating at 25 ꢁC using a 1 dm cell length.
Tosylate 1 [23], triflate 6 [24] of ethyl(S)-(ꢀ)lactate and
Zr(NMe2)4 [21] were prepared according to literature meth-
ods. Ti(NMe2)4 was purchased from Strem Chemicals.
Chiral HPLC: The chiral HPLC analyses were
performed on a screening unit composed of Merck D-7000
In the same conditions as those described above from
tosylate of ethyl lactate 1, 6.86 g of triflate of ethyl lactate
6 afforded, after purification on a silica column, 2.44 g of 2
(54% yield).

R. Laı¨ et al. / Journal of Organometallic Chemistry 693 (2008) 23–32
29
5.3. Cyclopentadiene ethyl lactate 2
fication on a silica gel column, 1.9 g of 7 (45% yield), 0.34 g
of 8 (8% yield) and 0.06 g of 9 (2% yield). The Rf of 8 and 9
are 0.47 and 0.40, respectively (hexane/Et2O 80/2). The
optical purity found for 7 was 95% by chiral HPLC. The
same value was found from 8 after protonation and
reprotonation.
1H NMR (CDCl3, 200 MHz): d 6.54, 6.43, 6.33, 6.17 (m,
3H, CH Cp), 4.15 (q, 2H, CH2CH3), 4.13 (q, 2H,
CH2CH3), 3.58 (q, 1H, CHCH3), 3.55 (q, 1H, CHCH3),
2.98 (m, 4H, CH2 Cp), 1.40 (d, 3H, CHCH3), 1.25 (t, 3H,
CH2CH3). 13C NMR (CDCl3, 50 MHz): d 173.7 (C@O),
146.0 (Cquat Cp), 145.5 (Cquat Cp), 134.0, 133.2, 132.1,
128.2, 127.5, 126.1 (CH Cp), 60.6 (CH2CH3), 42.0 (CH2
Cp), 41.4 (CHCH3), 41.3 (CH2 Cp), 40.6 (CHCH3), 17.5
(CHCH3), 16.7 (CHCH3), 14.5 (CH2CH3), 14.3 (CH2CH3).
Anal. Calc. for C10H14O2: C, 72.23; H, 8.42. Found: C,
72.45; H, 8.36%.
5.7. Indene ethyl lactate ((S)-ethyl 2-(1H -inden-3-yl)
propanoate) 7
1H NMR (CDCl3, 200 MHz): d 7.47–7.22 (m, 4H, CH
arom), 6.40 (m, 1H, CH indene), 4.16 (q, 7.2, 2H,
CH2CH3), 3.81 (qdd, 7.1, 1.5, 0.9, 1H, CHCH3), 3.37 (bs,
2H, CH2 indene), 1.55 (d, 7.1, 3H, CHCH3), 1.23 (t, 7.2,
3H, CH2CH3). 13C NMR (CDCl3, 50 MHz): d 174.3
(C@O), 144.4 (Cquat arom), 144.0 (Cquat arom), 143.2
(Cquat indene), 129.4 (CH indene), 126.1, 124.8, 123.9,
119.5 (CH arom), 60.9 (CH2CH3), 39.1 (CHCH3), 37.9
(CH2 indene), 16.6 (CHCH3), 14.1 (CH2CH3). Anal. Calc.
for C14H16O2: C, 77.74; H, 7.45. Found: C, 77.03; H,
5.4. Disubstituted cyclopentadiene ethyl lactate (diethyl
(2S,20S)-2,20-cyclopenta-1,3-diene-1,3-
diyldipropanoate and diethyl (2S,20S)-2,20-cyclopenta-1,3-
diene-1,4-diyldipropanoate) 3
1H NMR (CDCl3, 200 MHz): d 6.54–6.04 (m, 2H, CH
C5H4), 4.13 (m, 4H, CH2CH3), 3.77 (q, 1H, CHCH3),
3.46 (q, 1H, CHCH3), 2.99 (m, 4H, CH2 Cp), 1.37 (m,
6H, CHCH3), 1.23 (6H, m, CH2CH3). 13C NMR (CDCl3,
50 MHz): d 173.0 (C@O), 147.0 (Cquat Cp), 146.0 (Cquat
Cp), 134.0, 133.5, 132.3, 132.0 (CH Cp), 60.3 (CH2CH3),
42.1 (CH2 Cp), 41.5 (CHCH3), 41.3 (CH2 Cp), 40.6
(CHCH3), 17.6 (CHCH3), 16.9 (CHCH3), 14.5 (CH2CH3),
14.1 (CH2CH3). Anal. Calc. for C15H22O4: C, 67.76; H,
8.31. Found: C, 68.20; H, 8.56%.
25
7.64%. For the (S)-enantiomer, ½aꢂD ¼ þ25:6 (CHCl3,
c = 6.75).
5.8. Indene ethyl lactate ((S)-ethyl 2-(1H-inden-1-yl)
propanoate) 8
Only the NMR data of the major diastereoisomer will be
given.
1H NMR (CDCl3, 200 MHz): d 7.30 (m,4 H, CH arom),
6.86 (dd, 1 H, CH-sp2indene), 6.49 (dd, 1 H, CH-sp2in-
dene), 4.25 (q, 2 H, CH2–O), 3.88 (m, 1 H, CH-sp3 indene),
2.99 (q, 1 H, CH–CH3), 1.32 (t, 3 H, CH3–CH2), 0.84 (d, 3
H, CH3–CH). 13C NMR (CDCl3, 50 MHz): d 175.7
(C@O), 145.4 and 144.8 (Cquat arom), 136.2 and 132.7
(CH-sp2 indene), 127.0, 125.0, 122.7 and 121.2 (CH arom),
60.7 (CH2–O), 52.0 (CH-sp3 indene), 40.9 (CH–CH3), 12.4
(CH3–CH), 12.2 (CH3–CH2).
5.5. Synthesis of indene lactate ((S)-ethyl 2-(1H -inden-3-
yl)propanoate) 7 from tosylate of ethyl (S)-(ꢀ) lactate 1
A solution of LiInd (4.4 g, 36 mmol), prepared from
Indene and BuLi (2.5 M in hexane) in hexane, in 100 ml
THF was slowly added over 2 h to a solution of 10 g
(360 mmol) of tosylate of ethyl lactate 1 in THF (200 ml)
cooled at ꢀ78 ꢁC. The solution was stirred overnight at
room temperature. After evaporation of THF under vac-
uum, addition of a saturated aqueous solution of NaCl
extraction of the organic compounds was made with
Et2O (5 · 50 ml). The combined extracts were dried over
MgSO4 and Et2O was eliminated under vacuum leaving
the crude product as an oily brown residue. Purification
on a silica gel column afforded 4.5 g of 7 (56.5% yield).
The Rf of 7 is 0.43 (hexane/Et2O 80/2).
5.9. Disubstituted indene ethyl lactate (diethyl (2S,20S)-
2,20-(1H-indene-1,3-diyl)dipropanoate) 9
1H NMR (CDCl3, 400 MHz): d 7.35 (ddc, 7.4, 1H, CH
arom), 7.33 (ddc, 7.8, CH arom), 7.26 (tc, 7.4, 1H, CH
arom), 7.18 (ddd, 7.3, 1.1, 1H, CH arom), 6.31 (dd, 1.95,
1.2, 1H, CH indene), 4.24 (q, 7.1, 2H, CH2-9), 4.13 (qd,
7.1, 1.1, 2H, CH2-7), 3.86 (mc, 1H, CH-3), 3.76 (qt, 7.0,
1.2, 1H, CH-4), 2.98 (qd, 7.0, 5.0, 1H, CH-2), 1.52 (d,
7.1, 3H, CH3-6), 1.31 (t, 7.1, 3H, CH3-10), 1.18 (t, 7.1,
3H, CH3-8), 0.78 (d, 7.0, 3H, CH3-1). 13C NMR (CDCl3,
100 MHz): d 175.7 (C-19), 174.0 (C-18), 146.1 (C-11),
144.1 (C-16), 144.1 (C-17), 131.4 (C-5), 126.9 (C-14),
125.3 (C-13), 122.8 (C-12), 119.6 (C-15), 60.8 (C-7), 60.7
(C-9), 50.5 (C-3), 41.4 (C-2), 39.1 (C-4), 16.5 (C-6), 14.4
(C-10), 14.2 (C-8), 11.7 (C-1). Anal. Calc. for C19H24O4:
C, 72.12; H, 7.63. Found: C, 72.36; H, 7.45%.
Chiral HPLC: Chiralcel OJ (250 · 4.6 mm), hexane/iso-
propanol (90/10) as mobile phase, flow-rate = 1 ml/mn,
25 ꢁC, detection by UV at 254 nm and polarimeter, Rt(S,
+) = 7.48, Rt(R,ꢀ) = 11.90, k(S) = 1.45, k(R) = 2.90,
a = 2.00 and Rs = 6.17.
5.6. Synthesis of indene lactate ((S)-ethyl 2-(1H -inden-3-
yl)propanoate) 7 from triflate of ethyl lactate 6
In the same conditions as those described above, 4.9 g
(19.6 mmol) of triflate of ethyl lactate 6 afforded, after puri-
25
½aꢂ546 ¼ ꢀ58:6 (CH2Cl2, c = 0.365).

30
R. Laı¨ et al. / Journal of Organometallic Chemistry 693 (2008) 23–32
5.10. Synthesis of cyclopentadiene alcohol
((S)-2-(cyclopenta-1,3-dienyl)propan-1-ol and
(S)-2-(cyclopenta-1,4-dienyl)propan-1-ol) 10
ꢀ10 ꢁC. The resulting red solution was stirred at room tem-
perature during 24 h. Elimination of Zr(NMe2)3(OEt) by
filtration at ꢀ20 ꢁC, followed by chromatography of the fil-
trate on silica gel, afforded 12 as an oily yellow liquid
(0.26 g, 87.5% yield).
To a suspension of 0.96 g (25.4 mmol) LiAlH4 in 100 ml
of dry Et2O cooled at 0 ꢁC, a solution of 4.6 g (27.7 mmol)
of cyclopentadiene lactate 2 in 100 ml Et2O was slowly
added via canula. After 4 h stirring at room temperature
and monitoring by TLC (hexane/Et2O 70/30) water was
carefully added. Extraction of the aqueous phase with
Et2O and drying on MgSO4 of the combined organic frac-
tions afforded 3.4 g of crude 10. Purification on a silica gel
column yielded 2.8 g of pure 10 (81.4% yield).
1H NMR (C6D6, 200 MHz): d 6.65–5.92 (m, 3H, CH Cp),
3.45 and 3.44 (qd, 1H, CHCH3), 2.86 and 2.69 (m, 2H, CH2
Cp), 2.66, 2.63, 2.31 and 2.26 (s, 6H, CH3N), 1.47 and 1.38
(d, 3H, CH3CH). Anal. Calc. for C10H15NO: C, 72.70; H,
9.14; N, 8.48. Found: C, 72.60; H, 9.25; N, 8.41%.
5.13. (g4-Cycloocta-1,5-diene)(R,S)-2-(cyclopentadienyl)-
N,N-dimethylpropanamide rhodium(I) 14
1H NMR (CDCl3, 200 MHz): d 6.53–6.14 (m, 3H, CH
Cp), 3.61 (m, 2H, CH2OH), 2.99 (m, 1H, CH2 Cp), 2.92
(m, 1H, CH2 Cp), 2.80 (m, 1H, CHCH3), 1.38 (m, 1H,
OH),1.18 (d, 7.0, 1,5 H, CHCH3), 1.17 (d, 7.0, 1,5 H,
CHCH3). 13C NMR (CDCl3, 50 MHz): d 150.97 and
148.69 (Cquat Cp), 133.98, 132.83, 131.94, 131.00,
126.85, 126.44 (CH Cp), 67.41 and 66.69 (CH2OH), 41.23
and 40.97 (CH2 Cp), 37.68 and 36.87 (CHCH3), 17.01
and 16.12 (CHCH3). Anal. Calc. for C8H12O: C, 77.37;
H, 9.73. Found: C, 77.12; H, 9.52%.
At ꢀ50 ꢁC, 0.15 g (9 mmol) of 12 in 20 ml of THF was
reacted with 0.20 g (8.5 mmol) NaH. After 2 h stirring
the solution was slowly added at 0 ꢁC to a solution of
0.197 g (0.4 mmol) of [RhCl(COD)]2 in 20 ml THF. The
solution was stirred at room temperature for 24 h and at
reflux during 2 h. After evaporation of THF the product
was purified on a silica gel column to give 0.162 g of 14.
Crystallization from hexane/Et2O afforded yellow crystals
suitable for X-ray analysis.
Chiral HPLC: Chiralpak AD (250 · 4.6 mm), hexane/
isopropanol (90/10) as mobile phase, flow-rate = 1 ml/
mn, 25 ꢁC, detection by UV at 254 nm and circular dichro-
ism at 254 nm, Rt(+) = 6.63, Rt(ꢀ) = 8.77, k(+) = 1.14,
k(ꢀ) = 1.83, a = 1.60 and Rs = 3.48.
5.11. Synthesis of indene alcohol ((S)-2-(1H-inden-3-yl)-
propan-1-ol) 11
In the same conditions as those described for the prepa-
ration of 10, 0.87 g (23 mmol) of LiAlH4 with 4.85 g of 7
afforded 3.8 g ( 97.2% yield) of 11 after purification by col-
umn chromatography on silica gel.
Chiral HPLC: Chiralcel OD-H (250 · 4.6 mm), hexane/
isopropanol (90/10) as mobile phase, flow-rate = 1 ml/mn,
25 ꢁC, detection by UV at 254 nm and polarimeter, Rt(S,
+) = 6.45, Rt(R, ꢀ) = 8.39, k(S) = 1.12, k(R) = 1.75,
a = 1.57 and Rs = 4.87.
Preparative chiral HPLC: Ten successive injections of
500 ll of a 5 mg/ml solution of racemic 12 were done on
Chiralpak AD (250 · 10 mm), with hexane/isopropanol
(90/10) as mobile phase, flow-rate = 4.5 ml/mn, detection
by UV at 254 nm. The (+)-enantiomer was collected
between 6 and 8 min and the (ꢀ)-enantiomer between 9
and 11 min. About 12 mg of each enantiomer with an
enantiomeric excess higher than 99% were recovered.
25
1H NMR (CDCl3, 200 MHz): d 7.51–7.19 (m, 4H, CH
arom), 6.32 (m, 1H, CH indene), 3.81 (m, 2H, CH2OH),
3.37 (bs, 2H, CH2 indene), 3.11 (qd, 1H, CHCH3), 1.48
(bs, 1H, OH), 1.33 (d, 6.9, 3H, CH2CH3). 13C NMR
(CDCl3, 50 MHz): d 146.2 (Cquat arom), 144.7 (Cquat
arom), 144.6 (Cquat indene), 128.2 (CH indene), 126.1,
124.0, 123.9 and 119.3 (CH arom), 66.6 (CH2OH), 37.9
(CH2 indene), 35.3 (CHCH3), 16.4 (CHCH3). Anal. Calc.
for C12H14O: C, 82.72; H, 8.09. Found: C, 82.57; H,
8.01%. Interestingly, we observed that the sign of the rota-
tion was dependent on the nature of the solvent [25]. For
For the first eluted enantiomer, ½aꢂD ¼ þ30:6 (c = 0.74;
25
CHCl3). For the second enantiomer ½aꢂD ¼ þ30:4 (c = 0.74;
CHCl3).
1H NMR (CDCl3, 500 MHz): d 5.17, 5.02, 5.00, 4.90 (m,
4H, CH Cp), 3.91 (s br, 2H, COD, CH@CH), 3.82 (s br,
2H, COD, CH@CH), 3.71 (q, 1H, CHCH3), 3.13 (s, 3H,
NCH3), 2.95 (s, 3H, NCH3), 2.17-1.89 (m, ·2, 4H ·2,
COD CH2), 1.49 (d, 6.9, 3H, CHCH3). 13C NMR (CDCl3,
125.76 MHz): d 174.2 (C@O), 108.6 (d, 3.3, Cquat Cp),
85.8 (d, 3.88, 2 CH Cp), 85.6 (d, 3.42, CH Cp), 85.55 (d,
4.16, CH Cp), 85.53 (d, 3.9, CH Cp), 63.7 (d, 14.4,
CH@CH cod), 63.3 (d, 14.2, CH@CH cod), 37.7 (N–
CH3), 35.9 (N–CH3), 35.1 (CHCH3), 32.6 and 32.3 (CH2
cod), 20.6 (CH3CH). Anal. Calc. for C18H26NORh: C,
57.60; H, 6.97; N, 3.73. Found: C, 57.59; H, 7.10; N, 3.69%.
25
the (S)-enantiomer, ½aꢂD ¼ ꢀ4:5 (CHCl3, c = 0.6); +15.2
(ethanol, c = 0.6); +14.5 (hexane/isopropanol 9/1, c = 0.6).
5.12. (R,S)-2-(Cyclopenta-1,3-dienyl)-N,N-
dimethylpropanamide and (R,S)-2-(cyclopenta-1,4-dienyl)-
N,N-dimethylpropanamide 12
5.14. (ꢀ)-(g4-Cycloocta-1,5-diene)(S)-2-
(cyclopentadienyl)propan-1-ol rhodium(I) 15
A solution of racemic 2 (0.3 g, 1.8 mmol) in 15 ml tolu-
ene cooled at ꢀ10 ꢁC was slowly added to 0.485 g
(1.8 mmol) of Zr(NMe2)4 in 15 ml toluene kept at
In a schlenk, at ꢀ10 ꢁC, 0.162 g (1.3 mmol) of 10 was
dissolved in 50 ml of hexane and 1 ml of BuLi (2.5 M in

R. Laı¨ et al. / Journal of Organometallic Chemistry 693 (2008) 23–32
31
hexane) was added under stirring. A white solid was iso-
lated by filtration, dried under vacuum and dissolved in
50 ml of THF. To this solution was added 0.295 g
(0.6 mmol) of [RhCl(COD)]2. The solution was stirred at
room temperature during one week. After evaporation of
THF and addition of 50 ml Et2O, the solution was filtered
to give an orange oil after evaporation of the solvent Chro-
matography on a silica gel column afforded 0.30 g (68.7%
yield) of a yellow powder which can be crystallized in hex-
ane–Et2O to give pale yellow crystals.
Chiral HPLC: Chiralcel OD-H (250 · 4.6 mm), hexane/
isopropanol (95/5) as mobile phase, flow-rate = 1 ml/mn,
25 ꢁC, detection by UV at 254 nm and polarimeter, Rt(R,
+) = 9.86, Rt(S, ꢀ) = 11.00, k(R) = 2.23, k(S) = 2.61,
a = 1.17 and Rs = 1.55.
Preparative chiral HPLC: Seventy successive injections
of 200 ll of a 2 mg/ml solution of enantiomerically
enriched 15 were done on Chiralcel OD (250 · 10 mm),
with hexane/isopropanol (95/5) as mobile phase, flow-
rate = 5 ml/mn, detection by UV at 254 nm. The (S)-enan-
tiomer was collected between 11 and 15 minutes. About
15 mg of the (S)-enantiomer with an enantiomeric excess
higher than 99% were recovered.
1H NMR (CDCl3, 200 MHz): d 5.24, 5.18, 4.84, 4.76 (m,
4H, CH Cp), 3.91 (s br, 4H, COD, CH@CH), 3.81–3.46
(m, 3H, CH2OH and CH2OH), 2.66 (m, 1H, CHCH3),
2.45, 1.90 (m, ·2, 4H ·2, COD CH2), 1.16 (d, 7.0, 3H,
CHCH3). 13C NMR (CDCl3, 50 MHz): d 109.01 (d, 3.8,
Cquat Cp), 86.09 (d, 3.76, 2 CH Cp), 85.50 (d, 3.69, CH
Cp), 83.76 (d, 3.66, CH Cp), 67.08 (CH2OH), 63.87 (d,
6.5, CH@CH COD), 63.60 (d, 7.0, CH@CH COD), 34.98
(CHCH3), 32.31 and 32.26 (CH2 COD), 18.97 (CH3CH).
Anal. Calc. for C16H29O2Rh (C16H23ORh, 3H2O): C,
49.49; 7.47. Found: C, 49.97; H, 7.36%. For the (S)-enan-
25
tiomer, ½aꢂD ¼ ꢀ5:4 (CHCl3, c = 1.25).
X-ray structure determination: Single crystals were
mounted under inert perfluoropolyether at the tip of a glass
fibre and cooled in the cryostream of either the Stoe IPDS
diffractometer for 14 or the Oxford-Diffraction XCALI-
BUR CCD diffractometer for 15. Data were collected using
the monochromatic Mo Ka radiation (k = 0.71073).
The structures were solved by direct methods (SIR97 [26])
and refined by least-squares procedures on F2 using
SHELXL-97 [27]. All H atoms attached to carbon were intro-
duced in calculation in idealised positions and treated as
riding models. The H atoms attached to oxygen were
located in difference Fourier synthesis but they were treated
as riding on their parent O atoms. For compound 15, the
absolute configuration was deduced from the refinement
of the Flack’s enantiopole parameter [28,29] based on a
large number of Friedel pairs. The drawing of the mole-
cules was realised with the help of ORTEP32 [30]. Crystal
data and refinement parameters are shown in Table 1 (see
Tables 2–4).
Table 1
Crystal data and structure refinement for compounds 14 and 15
Identification code
14
15
Empirical formula
Formula weight
Temperature (K)
C
18H26NORh
(C16 H23ORh)8
2674.03
180(2)
0.71073
Monoclinic
C2
57.638(12)
8.3575(17)
26.026(5)
90.0
116.81(3)
90.0
11189(4)
4
1.587
1.207
5504
375.31
180(2)
0.71073
Triclinic
˚
Wavelength (A)
Crystal system
Space group
ꢀ
P1
˚
a (A)
7.9280(10)
9.1956(11)
11.6783(14)
74.851(14)
76.178(15)
82.934(15)
796.33(17)
2
Table 2
˚
˚
b (A)
Bond lengths (A) and angles (ꢁ) for CpRh(COD)CHMe(CONMe2) (14)
˚
c (A)
Rh(1)–CT1
Rh(1)–CT2
C(1)–C(2)
1.9041(4)
1.9883(4) Rh(1)–CT3
a (ꢁ)
b (ꢁ)
c (ꢁ)
2.0017(3)
1.431(3)
1.407(4)
1.428(3)
1.526(3)
1.347(3)
1.459(3)
1.517(3)
1.403(3)
1.530(3)
1.534(4)
1.410(3)
1.437(3)
1.513(3)
1.539(3)
1.221(3)
1.453(4)
1.419(4)
1.505(4)
1.532(3)
1.524(4)
C(2)–C(3)
C(3)–C(4)
C(4)–C(5)
C(11)–C(111)
C(12)–N(12)
N(12)–C(121)
C(26)–C(25)
C(25)–C(24)
C(24)–C(23)
C(23)–C(22)
C(1)–C(5)
3
˚
Volume (A )
C(1)–C(11)
C(11)–C(12)
C(12)–O(24)
N(12)–C(122)
C(21)–C(28)
C(21)–C(22)
C(28)–C(27)
C(27)–C(26)
Z
Dcalc (Mg/m3)
Absorption coefficient (mmꢀ1
F(000)
1.565
1.071
388
)
Crystal size (mm3)
Theta range (ꢁ)
Reflections collected
0.63 · 0.6 · 0.19 0.61 · 0.14 · 0.13
2.58–26.08
7717
2.84–30.51
58893
Independent reflections (Rint
Completeness (%)
)
2843 (0.0328)
90.0
29696 (0.0630)
99.5
CT1–Rh(1)–CT2
CT1–Rh(1)–CT3
C(2)–C(1)–C(5)
C(1)–C(2)–C(3)
C(4)–C(3)–C(2)
C(2)–C(1)–C(11)
C(1)–C(11)–C(111)
O(24)–C(12)–N(12)
N(12)–C(12)–C(11)
C(12)–N(12)–C(122)
C(12)–N(12)–C(121)
C(122)–N(12)–C(121) 115.0(2)
C(24)–C(25)–C(26)
C(25)–C(24)–C(23)
137.187(14)
135.204(12) CT2–Rh(1)–CT3
87.587(16)
107.1(2)
108.7(2)
108.69(18)
126.5(2)
Absorption correction
Maximum, minimum
transmission
Refinement method
Data/restraints/parameters
Goodness-of-fit on F2
R, wR2 [I > 2r(I)]
Multi-scan
0.8512 and
0.5256
Multi-scan
1.00000 and 0.47896
106.9(2)
108.5(2)
108.6(2)
126.6(2)
112.76(19)
121.4(2)
118.4(2)
125.7(2)
119.3(2)
C(3)–C(4)–C(5)
C(4)–C(5)–C(1)
C(1)–C(11)–C(12)
C(5)–C(1)–C(11)
F2
F2
2843/0/193
1.063
0.0258, 0.0689
29696/1/1305
0.840
C(111)–C(11)–C(12) 109.0(2)
O(24)–C(12)–C(11)
C(28)–C(21)–C(22)
C(21)–C(28)–C(27)
C(26)–C(27)–C(28)
C(25)–C(26)–C(27)
C(24)–C(23)–C(22)
C(21)–C(22)–C(23)
120.1(2)
124.8(2)
122.5(2)
111.9(2)
112.5(2)
112.0(2)
112.4(2)
R1 = 0.0478,
wR2 = 0.0862
R1 = 0.0915,
wR2 = 0.1034
ꢀ0.04(2)
R, wR2 (all data)
0.0264, 0.0693
Absolute structure parameter
Largest difference peak/hole
124.8(2)
122.7(2)
0.855/ꢀ0.843
1.141/ꢀ1.004
ꢀ3
˚
(e A
)

32
R. Laı¨ et al. / Journal of Organometallic Chemistry 693 (2008) 23–32
Table 3
6. Supplementary material
˚
Bond lengths (A) and angles (ꢁ) for C5H4CH(Me)(CH2OH)Rh(COD) (15)
Rh(1)–CT1
1.896(7)
2.089(7)
2.093(7)
2.099(7)
2.138(7)
1.444(8)
Rh(2)–CT2
1.894(7)
2.095(7)
2.099(7)
2.103(7)
2.133(7)
1.400(8)
CCDC 654660 and 654661 contain the supplementary
crystallographic data for this paper. These data can be
obtained free of charge from The Cambridge Crystallo-
graphic Data Centre via www.ccdc.cam.ac.uk/data_re-
quest/cif.
Rh(1)–C(15A)
Rh(1)–C(11A)
Rh(1)–C(12A)
Rh(1)–C(16A)
O(1)–C(112)
Rh(2)–C(22B)
Rh(2)–C(25B)
Rh(2)–C(21B)
Rh(2)–C(26B)
O(2)–C(212)
Rh(3)–CT3
1.896(7)
2.104(7)
2.108(7)
2.119(7)
2.147(7)
1.425(8)
Rh(4)–CT4
1.893(8)
2.087(7)
2.090(7)
2.094(7)
2.115(7)
1.412(7)
References
Rh(3)–C(35C)
Rh(3)–C(32C)
Rh(3)–C(31C)
Rh(3)–C(36C)
O(3)–C(312)
Rh(4)–C(41D)
Rh(4)–C(46D)
Rh(4)–C(45D)
Rh(4)–C(42D)
O(4)–C(412)
[1] R. La¨ı, A. Archavlis, R. Faure, M. Sanz, J. Chem. Soc., Dalton
Trans. (1997) 3259.
[2] R. La¨ı, S. Martin, Tetrahedron: Asymm. 7 (1996) 2783.
[3] R. La¨ı, S. Martin, R. Touret, Dalton Trans. (2006) 3478.
[4] R. La¨ı, J.-F. Berthome, I. Lyothier, C. Scheidecker, S. Martin, Inorg.
Chim. Acta (2003) 568.
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115.
[6] R.S. Threlkel, J.E. Bercaw, P.F. Seidler, J.M. Stryker, R.G. Bergman,
in: E. Vedjs (Ed.), Organic Synthesis, vol. 65, Organic Synthesis Inc.,
1987, p. 42.
[7] M. Sanz, Ph.D. Thesis, Universite Aix-Marseille III, 1998.
[8] F. Wochner, L. Zsolnai, G. Huttner, H.H. Brintzinger, J. Organomet.
Chem. 288 (1985) 69.
[9] R.L. Halterman, Chem. Rev. 92 (1992) 965.
[10] P. Vedso, R. Chauvin, Z. Li, B. Bernet, A. Vasella, Helv. Chim. Acta
77 (1994) 1631.
[11] E. Cesarotti, H.B. Kagan, J. Organomet. Chem. 162 (1978) 297.
[12] Z. Chen, K. Eriks, R.L. Halterman, Organometallics 10 (1991) 3449.
[13] R.L. Halterman, P.C. Vollhardt, Tetrahedron Lett. 27 (1986)
1461.
Rh(5)–CT5
1.887(8)
2.095(8)
2.096(7)
2.111(7)
2.111(8)
1.442(8)
Rh(6)–CT6
1.901(8)
2.084(7)
2.095(7)
2.112(7)
2.131(7)
1.411(7)
Rh(5)–C(56E)
Rh(5)–C(52E)
Rh(5)–C(51E)
Rh(5)–C(55E)
O(5)–C(512)
Rh(6)–C(66F)
Rh(6)–C(65F)
Rh(6)–C(61F)
Rh(6)–C(62F)
O(6)–C(612)
Rh(7)–CT7
1.897(8)
2.075(7)
2.088(7)
2.094(7)
2.111(7)
1.414(7)
Rh(8)–CT8
1.898(8)
2.107(8)
2.113(7)
2.115(7)
2.123(7)
1.441(8)
´
Rh(7)–C(75G)
Rh(7)–C(71G)
Rh(7)–C(72G)
Rh(7)–C(76G)
O(7)–C(712)
Rh(8)–C(85H)
Rh(8)–C(86H)
Rh(8)–C(81H)
Rh(8)–C(82H)
O(8)–C(812)
CT1–Rh(1)–CT11
CT1–Rh(1)–CT12
CT11–Rh(1)–CT12
O(1)–C(112)–C(111)
135.76(9)
135.5(2)
88.5(3)
CT2–Rh(2)–CT21
CT2–Rh(2)–CT22
CT21–Rh(2)–CT22
O(2)–C(212)–C(211)
135.09(6)
137.7(2)
87.2(3)
110.7(6)
115.5(6)
[14] R.L. Halterman, P.T.C. Vollhardt, M.E. Welker, D. Bla¨ser, R.
Boese, J. Am. Chem. Soc. 109 (1987) 8105.
[15] Z. Chen, R.L. Halterman, J. Am. Chem. Soc. 114 (1992) 2276.
[16] C.G. Venier, E.W. Casserly, J. Am. Chem. Soc. 112 (1990) 2808.
[17] R.A. Williams, K.F. Tesh, T.P. Hanusa, J. Am. Chem. Soc. 113
(1991) 4843.
[18] P. Beak, S.T. Kerrick, S. Wu, J. Chu, J. Am. Chem. Soc. 116 (1994)
3231.
[19] S.T. Kerrick, P. Beak, J. Am. Chem. Soc. 113 (1991) 9708.
[20] A. Trifonov, F. Ferri, J. Collin, J. Organomet. Chem. 582 (1999) 211.
[21] G.M. Diamond, R.F. Jordan, J.L. Petersen, J. Am. Chem. Soc. 118
(1996) 8024.
CT3–Rh(3)–CT31
CT3–Rh(3)–CT32
CT31–Rh(3)–CT32
O(3)–C(312)–C(311)
136.0(2)
134.84(9)
88.7(3)
CT4–Rh(4)–CT42
CT4–Rh(4)–CT41
CT42–Rh(4)–CT41
O(4)–C(412)–C(411)
137.85(10)
135.6(2)
86.6(3)
114.7(6)
112.3(6)
CT5–Rh(5)–CT52
CT5–Rh(5)–CT51
CT52–Rh(5)–CT51
O(5)–C(512)–C(511)
136.92(10)
134.7(2)
88.4(3)
CT6–Rh(6)–CT62
CT6–Rh(6)–CT61
CT62–Rh(6)–CT61
O(6)–C(612)–C(611)
137.2(2)
135.20(10)
87.5(3)
109.6(6)
112.2(6)
CT7–Rh(7)–CT71
CT7–Rh(7)–CT72
CT71–Rh(7)–CT72
O(7)–C(712)–C(711)
137.02(9)
135.5(2)
87.3(3)
CT8–Rh(8)–CT82
CT8–Rh(8)–CT81
CT82–Rh(8)–CT81
O(8)–C(812)–C(811)
136.40(12)
135.13(19)
88.4(3)
[22] D.D. Perrin, W.L.F. Armarego, Purification of Laboratory Chemi-
cals, Pergamon Press, Oxford, 1988.
111.1(6)
111.0(6)
[23] J. Gabard, A. Collet, New J. Chem. 10 (1986) 685.
[24] F. Effenberger, U. Burkard, J. Willfahrt, Liebigs Ann. Chem. (1986)
314.
Table 4
Hydrogen bonding interactions for compound 15
[25] C. Roussel, N. Vanthuyne, M. Serradeil-Albalat, J.C. Vallejos, J.
Chromatogr., Sect. A 995 (2003) 79.
[26] A. Altomare, M.C. Burla, M. Camalli, G.L. Cascarano, C. Giaco-
vazzo, A. Guagliardi, A.G.G. Moliterni, G. Polidori, R. Spagn, J.
Appl. Cryst. 32 (1999) 115.
[27] G.M. Sheldrick, SHELXL 97. Program for Crystal Structure Refine-
ment, University of Go¨ttingen, Germany, 1997.
[28] H.D. Flack, Acta Crystallogr., Sect. A 39 (1983) 876.
[29] G. Bernardinelli, H.D. Flack, Acta Crystallogr., Sect. A 41 (1985)
500.
D–H
Hꢁ ꢁ ꢁA
Dꢁ ꢁ ꢁA
\(DHA)
O1–H1ꢁ ꢁ ꢁO4
O4–H4ꢁ ꢁ ꢁO7
O7–H7ꢁ ꢁ ꢁO5
O5–H5ꢁ ꢁ ꢁO1i
O3–H3ꢁ ꢁ ꢁO2
O2–H2ꢁ ꢁ ꢁO6
O6–H6ꢁ ꢁ ꢁO8
O8–H8ꢁ ꢁ ꢁOii
0.84
0.84
0.84
0.85
0.84
0.84
0.84
0.85
1.86
1.91
2.05
1.82
1.81
1.89
1.78
1.76
2.695(7)
2.679(8)
2.731(7)
2.673(8)
2.631(8)
2.645(8)
2.621(7)
2.607(8)
177.4
151.3
137.5
179.2
165.6
149.3
178.1
159.0
[30] L.J. Farrugia, J. Appl. Cryst. 30 (1997) 565.
Symmetry codes: (i) 1 x, y + 1, z; (ii) x, y ꢀ 1, z.