Stereoselective tricarbonylchromium migration reactions in axially chiral biaryl chromium complexes

Article abstract of DOI:10.1016/j.jorganchem.2006.04.051

The tricarbonylchromium group in thermodynamically unstable biaryl chromium complexes with a coordinating heteroatom at the side chain stereoselectively migrated to the other arene face to release the steric repulsion.

Full text of DOI:10.1016/j.jorganchem.2006.04.051

Journal of Organometallic Chemistry 692 (2007) 678–684
www.elsevier.com/locate/jorganchem
Stereoselective tricarbonylchromium migration reactions in
axially chiral biaryl chromium complexes
a,
a
a
a
Ken Kamikawa *, Kouta Nishino , Tomohiro Sakamoto , Shunsuke Kinoshita ,
a
b,
*
Hiroyuki Matsuzaka , Motokazu Uemura
a
Department of Chemistry, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
b
Kyoto Pharmaceutical University, Misasagi, Yamashina, Kyoto 640-8412, Japan
Received 28 February 2006; accepted 18 April 2006
Available online 3 September 2006
Abstract
The tricarbonylchromium group in thermodynamically unstable biaryl chromium complexes with a coordinating heteroatom at the
side chain stereoselectively migrated to the other arene face to release the steric repulsion.
Ó 2006 Elsevier B.V. All rights reserved.
Keywords: Arene–chromium complex; Planar chirality; Stereoselective migration; Mobile chiral auxiliary
1. Introduction
retention of planar chirality, the migration between two
different and nonadjacent six-membered rings has never
been examined so far.
Metal migration from one site of a coordinated organo-
metallic ligand to another is a well-known process occur-
ring in oligocyclic fused p-arene complexes due to the
haptotropic ring slippage from g6 to g4 coordination mode
[1]. This kind of migration has been actively studied in
naphthalene tricarbonylchromium complexes and widely
utilized for useful organometallic reagents [2]. On the other
hand, the migration of a tricarbonylchromium group
between two different and nonadjacent six-membered rings,
such as in biphenyl tricarbonylchromium complexes, was
reported by several groups [3]. One attractive yet trouble-
some feature of these tricarbonylchromium migrations to
the arene ring having different substituents at ortho or meta
positions is the stereoselectivity based on planar chirality,
which may lead to the formation of an enantiomer or a dia-
stereomer via the migration reaction. Although the tricar-
bonylchromium slippage in oligocyclic fused p-arene
complexes was proven to be an equilibrium process with
We reported previously the inversion of planar chirality
in thermodynamically unstable syn-biaryl chromium com-
plexes having a coordinating heteroatom at the side chain
of arene–chromium complexes under thermal conditions
(Scheme 1) [4].
The tricarbonylchromium migration to another arene B
ring in syn-biaryl chromium complexes, which is attractive
in terms of transfer of planar chirality as a mobile chiral
auxiliary, is expected [5]. Thus, asymmetric reactions lead-
ing to regio- and stereoselective tricarbonylchromium
migrations between two different and nonadjacent six-
membered rings have much room for further development,
utilizing planar chiral arene–chromium complexes.
Herein, we report in detail stereoselective tricarbonyl-
chromium migration to another arene ring and its applica-
tion to the stereoselective synthesis of axially chiral biaryl
tricarbonylchromium complexes.
2. Results and discussion
*
Corresponding authors. Tel.: +81 722 54 9698; fax: +81 722 54 9931.
We previously examined the inversion of planar chira-
E-mail addresses: kamikawa@c.s.osakafu-u.ac.jp (K. Kamikawa),
lity in thermodynamically unstable syn-biaryl chromium
muemura@mb.kyoto-phu.ac.jp (M. Uemura).
0022-328X/$ - see front matter Ó 2006 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2006.04.051

K. Kamikawa et al. / Journal of Organometallic Chemistry 692 (2007) 678–684
679
Me
R
R
B
(OC)3Cr
R
A
Me
OMe
Me
aromatic
solvent
n
-Bu2O,
OMe
OMe
Cr(CO)3
anti
(CH2Cl)2
Cr(CO)3
syn
anti
R = CH2OH, CH2OMe,
CH(OMe)2, CH2NHMe
R = Me, CHO, CH=NMe,
CO2Me
Face inversion
Axial isomerization
Scheme 1. Axial isomerization vs. planar chirality inversion.
complexes under thermal conditions, and found that the
coordinating heteroatom at the sp3-benzylic position plays
an important role in lowering the arene–chromium bond
cleavage of the complexes [4]. Thus, we examined the ste-
reochemical behavior under thermal conditions of syn-bia-
ryl chromium complexes having a coordinating heteroatom
at the sp3-benzylic position of the chromium-uncomplexed
arene ring.
Initially, starting thermodynamically unstable syn-biaryl
chromium complexes were prepared by stereoselective
Suzuki–Miyaura cross-coupling reactions utilizing the pla-
nar chirality of arene–chromium complexes developed by
our group. The results are summarized in Table 1. In most
cases, desired biaryl chromium complexes 3 were obtained
in moderate to good yields with high diastereoselectivities.
With the starting syn-biaryl chromium complexes in
hand, we next examined the stereoselective migration reac-
tions under thermal conditions (Table 2). syn-(g-1,2,3,
4,5,6)-Tricarbonyl(2-methoxy-6-methyl-20-hydroxymethyl-
biphenyl)chromium complex (3aa) was refluxed in a mix-
ture of di-n-butyl ether and dichloroethane to give tricar-
bonylchromium migration products 6aa (36%) and 7aa
(8%) as an 82:18 diastereomeric mixture along with 37%
yield of a de-chromium product (entry 1). The relative ste-
reochemistry of these complexes was determined from the
1
chemical shifts in the H NMR spectra [6]. Neither central
bond rotation nor chromium migration to the reversed
arene A ring was observed under the conditions employed.
Thus, the Cr(CO)3 fragment migrated exclusively to the
arene ring that was substituted with a hydroxymethyl
group regardless of the electron density of the arene ring.
In addition, complex 6aa was formed as a major diastereo-
mer to avoid the steric repulsion between the Cr(CO)3 frag-
ment and the methyl group, which is a larger substituent
than a methoxy group. We next examined the migration
reactions utilizing complex 3ab that hydroxymethyl group
on the B ring was protected with a methoxymethyl group
(entry 2), and found that the reaction, although time-con-
suming, gave migration product 6ab, presumably due to
the lowering of the coordinating ability by protection of
Table 1
Stereoselective synthesis of axially chiral biaryls by Suzuki–Miyaura cross-coupling reactions
OR3
R4
R2
R1
R1
B
B
Br
Pd(PPh3)4
R3O
+
A
A
Na2CO3
MeOH
R4
R1
R2
OR3
O
(HO)2B
R2
Cr(CO)3
R4
Cr(CO)3
3
70 ˚C, 30 min
Cr(CO)3
2
1
4
OR3
2a: R3, R4 = H
1a: R1 = Me, R2 = OMe
1b: R1 = Et, R2 = OMe
1c: R1 = Me, R2 = H
R2
2b: R3 = MOM, R4 = H
2c: R3 = H, R4 =OMe
2d: R3 = MOM, R4 = OMe
R1
R4
Cr(CO)3
5
Entry
Complex
Boronic acid
Product (yield, (%))
Ratio (3:4)
3
4
5
1
2
3
4
5
6
1a
1a
1b
1b
1c
1c
2a
2b
2a
2b
2c
2d
3aa (54)
3ab (81)
3ba (40)
3bb (85)
3cc (28)
3cd (72)
5aa (14)
>98:<2
>98:<2
>98:<2
>98:<2
>98:<2
94:6
5ba (20)
5cc (14)
4cd (5)

680
K. Kamikawa et al. / Journal of Organometallic Chemistry 692 (2007) 678–684
Table 2
Stereoselective tricarbonylchromium migration reactions under thermal conditions
(CO)3Cr
B
(CO)3Cr
B
R4
R4
R1
R4
R1
1)
n
-Bu2O : (CH2Cl)2
R1
B
( = 1 : 1)
120 ˚C
A
A
A
R2
OR3
R2
R2
OR3
OR3
Cr(CO)3
3
6
7
(CO)3Cr
B
R4
R1
3aa: R1 = Me, R2 = OMe, R3, R4 = H
3ab: R1 = Me, R2 = OMe, R3 = MOM, R4 = H
3ba: R1 =Et, R2 = OMe, R3, R4 = H
A
3bb: R1 =Et, R2 = OMe, R3 = MOM, R4 = H
3cc: R1 =Me R2 = H, R3 = H, R4 = OMe
3cd: R1 =Me R2 = H, R3 = MOM, R4 = OMe
R2
OR3
Cr(CO)3
8
Entry
Complex
Time (h)
Products (yield, (%))
6
7
8
1
2
3
4
5
6
3aa
3ab
3ba
3bb
3cc
3cd
1.5
4.0
1.5
4.0
2.0
4.0
6aa (36)
6ab (23)
6ba (45)
6bb (17)
6cc (47)
7aa (8)
7ab (2)
8ab (15)
8bb (8)
8cc (3)
8cd (1)
the hydroxyl group. Furthermore, bis-tricarbonylchro-
mium coordinated product 8ab was obtained, which was
not isolated in the migration reaction utilizing complex
3aa having a hydroxyl group. With the intent of improving
the diastereoselectivity, we next examined the migration
reaction using complexes 3ba and 3bb, both of which have
an ethyl group on the A ring (entries 3 and 4). As expected,
the diastereoselectivity was improved by increasing the ste-
ric demand to discriminate the arene faces. Furthermore,
when the ortho-three-substituted biaryl complex 3cc having
one methoxy group and one hydroxymethyl group on the B
ring was used, the migration reaction proceed smoothly to
give 6cc in moderate yield with high diastereoselectivity
(entry 5). In contrast, the migration reaction utilizing com-
plex 3cd having a methoxymethyl ether group was unsuc-
cessful, and 60% of the starting material was recovered
(entry 6).
butyl ether and dichloroethane was heated at 120 °C for
2 h, and the reaction products were analyzed after acetyla-
tion (Scheme 2). The Cr(CO)3 fragment of complex 3aa
migrated to the B ring of biaryl compound 9 to give biaryl
complex 11 as the major chromium complex. These results
indicate that the migration of chromium in 3aa having ben-
zylic heteroatom substituents under thermal conditions
proceeds in an intermolecular fashion.
In addition, from the finding that the direct chromium
complexation of chromium-free biaryl compound gave a
variety of regio- and stereoisomers, the hypothesis that tri-
carbonylchromium migration is attributed to the recom-
plexation of the Cr(CO)3L3 (L = solvent) species
generated by de-chromium complexation can be ruled out
[4,6].
On the basis of these experiments, a plausible mecha-
nism for the stereoselective chromium migration is pro-
posed in Scheme 3. Intramolecular coordination of
chromium with the benzylic heteroatom on the B ring
occurs and a coordinating solvent assists slippage for a
g4-syn-12 intermediate of syn-biphenyl complex 3. Subse-
quently, another benzylic heteroatom of the syn-biaryl
To clarify the reaction mechanism, we next studied the
crossover reaction between a syn-biaryl chromium complex
and a chromium-free biaryl compound under thermal con-
ditions. A 1:1 mixture of syn-biaryl chromium complex 3aa
and 2,6-dimethoxy-20-hydroxymethyl biphenyl (9) in di-n-
(OC)3Cr
Me
(OC)3Cr
(a) n-Bu2O,
(CH2Cl)2,
120 ºC, 2 h
B
OMe
OMe
A
+
3aa
+
A
(b) Ac2O, Pyr.
A
OMe
OMe
10 12 %
Scheme 2. Crossover reaction.
OH
OMe
OAc
OAc
9
11 48 %

K. Kamikawa et al. / Journal of Organometallic Chemistry 692 (2007) 678–684
681
OMe
A
LnCr
B
OMe
B
Et
R3
Cr(CO)3
O
A
OMe O
R3
Et
OR3
η4-syn- 12
Cr(CO)3
3
Et
R3 = H or MOM
Cr(OC)3
Cr(CO)3
OMe
OMe
B
Et
O
OMe
B
R3
OMe O
LnCr
A
η4-syn- 13
Et
OR3
A
R3
Et
OR3
Cr(CO)3
Et
8
Cr(CO)3
OMe
B
A
Et
OR3
6
Scheme 3. Proposed mechanism.
chromium complex coordinates with the chromium of the
g4-syn-12 intermediate for dual activation. Then, chro-
mium migration proceeds from the less hindered side of
the B ring regardless of electron density. As a result, bis-tri-
carbonylchromium coordinated biaryl 8 and uncomplexed
biaryl are generated. Next, the second migration reaction
proceeds between 8 and uncomplexed biaryl via the g4-
syn-13 intermediate in a similar manner. In this way, a tri-
carbonylchromium group stereoselectively migrates to the
less hindered side of the B ring.
As the planar chirality of biaryl chromium complex was
transferred to another arene ring by the stereoselective tri-
carbonylchromium migration reactions, we next studied
the stereoselective functionalization at the side chain utiliz-
ing the newly generated planar chirality of the complexes
(Scheme 4). The stereoselective addition to the ortho formyl
group of biaryl chromium complexes was examined,
because planar chiral o-substituted benzaldehyde chro-
mium complexes are versatile compounds in asymmetric
synthesis [7]. The hydroxymethyl group of complex 6ba
was oxidized with dimethylsulfoxide and trifluoroacetic
anhydride to form the formyl group. The resulting benzal-
dehyde chromium complex 14 was treated with MeLi to
give predominantly biaryl secondary alcohol 15 in a ratio
of >98:<2. The high diastereoselectivity of the addition
of MeLi to the chromium-complexed benzaldehyde is due
to an exo attack of nucleophile at the anti-oriented car-
bonyl group with an ortho-substituent due to stereoelec-
tronic effect [8].
Therefore, we succeeded in controlling not only the axial
chirality but also the chirality at the side chain from a sin-
gle mobile chiral auxiliary.
Me
Cr(CO)3
Cr(CO)3
O
OH
OMe
Cr(CO)3
DMSO,
OH
H
OMe
H
MeLi
B
B
B
OMe
(CF3CO)2O
A
A
Et3N
40%
A
-78 ˚C
90%
Et
6ba
Scheme 4. Stereoselective nucleophilic reaction utilizing a mobile chiral auxiliary.
Et
Et
15
14

682
K. Kamikawa et al. / Journal of Organometallic Chemistry 692 (2007) 678–684
3. Conclusion
(1H, d, J = 6.7 Hz), 5.33 (1H, d, J = 13.0 Hz), 5.71 (1H,
t, J = 6.7 Hz), 7.01 (1H, d, J = 7.2 Hz), 7.25 (1H, t,
J = 7.2 Hz), 7.43 (1H, t, J = 7.2 Hz), 7.72 (1H, d,
J = 7.2 Hz); 13C NMR (125 MHz, CDCl3) d 13.7, 26.4,
55.5, 55.9, 66.4, 72.0, 83.7, 94.7, 96.4, 101.7, 117.4,
126.5, 127.7, 128.5, 129.6, 132.6, 137.4, 140.9, 233.4; IR
(CHCl3) 3689, 2931, 2851, 1963, 1889, 1601, 1576,
1506 cmꢁ1; MS (relative intensity) m/z 422 (M, +3), 394
(2), 366 (5), 338 (63), 278 (100); HRMS calcd for
C21H22O6Cr: 422.0821, found 422.0823.
In conclusion, we demonstrated the stereoselective
tricarbonylchromium migration reactions of thermody-
namically unstable biaryl chromium complexes. The incor-
poration of a directing group such as a hydroxyl group
plays an important role in the migration of the tricarbonyl-
chromium group.
Together, these results indicate that we could control
both the axial chirality and the chirality at the side chain
from a single chiral source.
4.1.4. ðSꢀax; RpꢀlÞ-Tricarbonyl[(1,2,3,4,5,6-g)-2-methyl-20-
methoxy-60-hydroxymethylbiphenyl]chromium complex 3cc
1H NMR (500 MHz, CDCl3) d 1.93 (3H, s), 1.98 (1H,
br), 3.71 (3H, s), 5.03 (1H, d, J = 12.2 Hz), 5.16–5.20
(2H, m), 5.35 (1H, d, J = 12.2 Hz), 5.60 (1H, d, J =
6.2 Hz), 5.65 (1H, t, J = 6.2 Hz), 6.88 (1H, d, J = 8.0
Hz), 7.28 (1H, d, J = 8.0 Hz), 7.41 (1H, t, J = 8.0 Hz);
13C NMR (125 MHz, CDCl3) d 19.5, 55.7, 62.0, 87.7,
90.6, 96.4, 100.1, 107.1, 110.0, 112.1, 121.9, 122.6, 129.8,
139.3, 157.9, 233.6; IR (CHCl3) 3358, 2994, 1970, 1890,
1563 cmꢁ1; MS (relative intensity) m/z 364 (M, +8), 336
(13), 308 (11), 280 (100), 247 (61), 232 (40), 228 (32);
HRMS calcd for C18H16O5Cr: 364.0405, found 364.0404.
4. Experimental
4.1. Preparation for syn-biaryl mono tricarbonylchromium
complexes
Complexes 3aa–3cd were prepared by reported stereose-
lective cross-coupling reaction of corresponding arene–
chromium complexes with aryl boronic acids, in addition,
complexes 3aa, 5aa, 3cd, 4cd were known compounds [9].
4.1.1. ðSꢀax; SpꢀlÞ-Tricarbonyl[(1,2,3,4,5,6-g)-2-methoxy-6-
methyl-20-methoxymethoxy methylbiphenyl]chromium
complex 3ab
1H NMR (500 MHz, CDCl3) d 1.99 (3H, s), 3.47 (3H, s),
3.68 (3H, s), 4.83–4.90 (4H, m), 5.06 (1H, d, J = 6.6 Hz),
5.35 (1H, d, J = 13.4 Hz), 5.67 (1H, d, J = 6.6 Hz), 7.01
(1H, d, J = 7.6 Hz), 7.26 (1H, t, J = 7.6 Hz), 7.43 (1H, t,
J = 7.6 Hz), 7.73 (1H, d, J = 7.6 Hz); 13C NMR
(125 MHz, CDCl3) d 20.9, 55.4, 55.8, 66.4, 72.1, 86.0,
94.5, 96.3, 101.6, 111.5, 126.6, 127.5, 128.5, 129.8, 132.2,
133.4, 137.7, 140.8; IR (CHCl3) 2947, 1974, 1900, 1668,
1601, 1573, 1269 cmꢁ1; MS (relative intensity) m/z; 408
(M, +2), 380 (1), 352 (5), 324 (52), 264 (90), 249 (100);
HRMS calcd for C20H20O6Cr: 408.0665, found 408.0663.
4.1.5. Tricarbonyl[(1,2,3,4,5,6-g)-2-methoxy-6-ethyl-20-
hydroxymethylbenzophenone]chromium complex 5ba
1H NMR (500 MHz, CDCl3) d 1.07 (3H, t, J = 7.6 Hz),
2.44–2.55 (2H, m), 2.61 (3H, s), 3.67 (1H, br s), 4.72–4.77
(3H, m), 4.85 (1H, dd, J = 5.6, 12.9 Hz), 4.96 (1H, d,
J = 6.7 Hz), 5.64 (1H, t, J = 6.7 Hz), 7.33–7.37 (1H, m),
7.56–7.57 (1H, m), 7.67 (1H, d, J = 7.8 Hz); 13C NMR
(125 MHz, CDCl3) d 14.1, 25.2, 56.1, 64.4, 70.0, 82.6,
94.1, 103.6, 115.4, 127.6, 130.5, 132.2, 133.6, 136.0, 140.6,
142.4, 194.4, 232.0; IR (CHCl3) 2989, 1973, 1896, 1572,
1456 cmꢁ1; MS (relative intensity) m/z 406 (M, +3), 388
(2), 364 (5), 350 (10), 322 (50), 293 (66), 278 (100); HRMS
calcd for C20H18O6Cr: 406.0509, found 406.0512.
4.1.2. ðSꢀax; SpꢀlÞ-Tricarbonyl[(1,2,3,4,5,6-g)-2-methoxy-6-
ethyl-20-hydroxymethyl biphenyl]chromium complex 3ba
1H NMR (500 MHz, CDCl3) d 1.04 (3H, t, J = 7.3 Hz),
2.01 (1H, br), 2.17–2.29 (2H, m), 3.66 (3H, s), 4.90 (1H, d,
J = 6.4 Hz), 5.09 (1H, d, J = 6.4 Hz), 5.19–5.21 (2H, m),
5.73 (1H, t, J = 6.4 Hz), 7.00 (1H, d, J = 7.7 Hz), 7.27 (1H,
t, J = 7.7 Hz), 7.44 (1H, t, J = 7.7 Hz), 7.72 (1H, d, J =
7.7 Hz); 13C NMR (125 MHz, CDCl3) d 13.7, 26.5, 55.8,
56.0, 62.0, 72.4, 83.9, 94.9, 117.5, 126.8, 128.7, 128.8, 129.6,
132.6, 139.4, 140.8, 233.4; IR (CHCl3) 3690, 2925, 2853,
1963, 1886, 1601, 1571 cmꢁ1; MS (relative intensity) m/z
378 (M, +3), 350 (8), 322 (11), 294 (100), 276 (28), 261 (53);
HRMS calcd for C19H18O5Cr: 378.0559, found 378.0559.
4.1.6. Tricarbonyl[(1,2,3,4,5,6-g)-2-methyl-20-methoxy-60-
hydroxymethyl benzophenone]chromium complex 5cc
1H NMR (500 MHz, CDCl3) d 1.95 (1H, s), 2.51 (3H, s),
3.75 (3H, s), 4.54-4.68 (2H, m), 4.98 (1H, t, J = 6.3 Hz),
5.07 (1H, d, J = 6.3 Hz), 5.65–5.70 (2H, m), 6.91 (1H, d,
J = 8.0 Hz), 7.15 (1H, d, J = 8.0 Hz), 7.45 (1H, t,
J = 8.0 Hz); 13C NMR (125 MHz, CDCl3) d 20.8, 55.7,
63.3, 86.4, 91.8, 96.0, 98.1, 110.5, 112.7, 121.9, 127.5,
131.9, 140.9, 154.7, 156.6, 197.0, 231.1; IR (CHCl3) 3360,
3006, 1977, 1900, 1600 cmꢁ1; MS (relative intensity) m/z
392 (M, +7), 374 (24), 336 (43), 308 (93), 275 (100); HRMS
calcd for C19H16O5Cr: 392.0352, found 392.0355.
4.1.3. ðSꢀax; SpꢀlÞ-Tricarbonyl[(1,2,3,4,5,6-g)-2-methoxy-6-
ethyl-20-methoxymethoxymethylbiphenyl]chromium
complex 3bb
4.2. General procedure for stereoselective
tricarbonylchromium migration reaction
1H NMR (500 MHz, CDCl3)
d
1.05 (3H, t,
J = 7.5 Hz), 2.17–2.35 (2H, m), 3.47 (3H, s), 3.66 (3H,
s), 4.83–4.89 (3H, m), 4.99 (1H, d, J = 13.0 Hz), 5.06
A solution of syn biaryl complex 3 (0.25 mmol) in mix-
ture of n-dibutylether (2 mL) and dichroloethane (2 mL)

K. Kamikawa et al. / Journal of Organometallic Chemistry 692 (2007) 678–684
683
was stirred at 120 °C for 2 h. The solvent was removed
4.2.4. ðSꢀax; RpꢀlÞ-Tricarbonyl[(1,2,3,4,5,6-g)-2-methoxy-6-
under reduced pressure, and the residue was purified by sil-
ica gel chromatography to give tricarbonylchromium
migrated biaryl complex.
acetoxymethyl-20-methylbiphenyl]chromium complex 6cc0
1H NMR (500 MHz, CDCl3) d 1.99 (3H, s), 2.09 (3H, s),
3.65 (3H, s), 4.59 (1H, d, J = 12.8 Hz), 4.65 (1H, d,
J = 12.8 Hz), 4.98 (1H, d, J = 6.2 Hz), 5.04 (1H, d,
J = 6.2 Hz), 5.73 (1H, t, J = 6.2 Hz), 7.22–7.32 (3H, m),
7.42 (1H, d, J = 6.1 Hz); 13C NMR (125 MHz, CDCl3) d
19.6, 20.5, 56.0, 62.9, 71.2, 83.3, 94.5, 104.4, 108.5, 126.5,
129.0, 129.7, 130.2, 134.1, 137.6, 142.4, 169.9, 232.7; IR
(CHCl3) 3000, 1968, 1893, 1738, 1562 cmꢁ1; MS (relative
intensity) m/z 406 (M, +6), 350 (4), 322 (20), 307 (15),
270 (100); HRMS calcd for C20H18O6Cr: 406.0509, found
406.0505.
Complexes 6aa, 6ba, 6cc and 8cc were characterized
after transformed to acetylated complexes 10, 6ba0, 6cc0
and 8cc0 respectively. Complex 10 was known compound
[4a].
4.2.1. ðSꢀax; SpꢀlÞ-Tricarbonyl[(1,2,3,4,5,6-g)-2-
methoxymethoxymethyl-20-methoxy-60-
methylbiphenyl]chromium complex 6ab
1H NMR (400 MHz, CDCl3) d 2.12 (3H, s), 3.21 (3H, s),
3.89 (3H, s), 4.00 (1H, d, J = 12.5 Hz), 4.21 (1H, d,
J = 12.5 Hz), 4.47 (1H, d, J = 6.6 Hz), 4.57 (1H, d, J =
6.6 Hz), 5.09 (1H, t, J = 6.8 Hz), 5.41 (1H, d,
J = 6.8 Hz), 5.51 (1H, d, J = 6.8 Hz), 5.62 (1H, t,
J = 6.8 Hz), 6.81–6.88 (2H, m), 7.26 (1H, t, J = 7.9 Hz);
13C NMR (100 MHz, CDCl3) d 21.0, 30.5, 55.1, 55.2,
66.1, 85.3, 86.8, 95.1, 96.4, 98.3, 108.7, 110.5, 122.6,
129.5, 135.6, 139.4, 155.1, 233.3; IR (CHCl3) 2991, 1966,
1891 cmꢁ1; MS (relative intensity) m/z 408 (M, +1), 324
(50), 264 (83), 249 (100); HRMS calcd for C20H20O6Cr:
408.0656, found 408.0666.
4.2.5. ðSꢀax; Rpꢀl; SpꢀlÞ-Di-tricarbonyl[(1,2,3,4,5,6-g)-
(10,20,30,40,50,60-g)-2-methoxy-6-methyl-20-
methoxymethoxymethylbiphenyl]chromium complex 8ab
1H NMR (400 MHz, CDCl3) d 2.16 (3H, s), 3.46 (3H,
s), 3.90 (3H, s), 4.34 (1H, d, J = 13.7 Hz), 4.83–4.87 (3H,
m), 4.93 (1H, d, J = 13.7 Hz), 5.06 (1H, t, J = 6.6 Hz),
5.18 (1H, d, J = 6.6 Hz), 5.35 (1H, t, J = 6.6 Hz), 5.65–
5.72 (3H, m); 13C NMR (100 MHz, CDCl3) d 22.4,
55.7, 55.8, 65.8, 72.1, 86.1, 92.9, 94.4, 96.4, 112.2,
126.6, 127.5, 128.0, 128.6, 132.3, 158.3, 170.7, 232.5,
232.6; IR (CHCl3) 3006, 2949, 1963, 1892 cmꢁ1; MS (rel-
ative intensity) m/z 544 (M, +3), 459 (20), 345 (100), 248
(65); HRMS calcd for C23H20O9Cr2: 543.9918, found
543.9906.
4.2.2. ðSꢀax; SpꢀlÞ-Tricarbonyl[(1,2,3,4,5,6-g)-2-
acetoxymethyl-20-methoxy-60-ethylbiphenyl]chromium
complex 6ba0
1H NMR (500 MHz, CDCl3) d 1.05 (3H, t, J = 7.5 Hz),
1.99 (3H, s), 2.39–2.57 (2H, m), 3.90 (3H, s), 4.58 (1H, d,
J = 13.2 Hz), 4.75 (1H, d, J = 13.2 Hz), 5.10 (1H, t,
J = 6.1 Hz), 5.38 (1H, d, J = 6.1 Hz), 5.44 (1H, d, J =
6.1 Hz), 5.59 (1H, t, J = 6.1 Hz), 6.82 (1H, d,
J = 8.0 Hz), 6.92 (1H, d, J = 8.0 Hz), 7.33 (1H, t,
J = 8.0 Hz); IR (CHCl3) 2972, 2361, 1338, 1969, 1898,
1727, 1599, 1577 cmꢁ1; MS (relative intensity) m/z 420
(M, +3), 364 (6), 336 (79), 321 (82), 305 (41); HRMS calcd
for C21H20O6Cr: 420.0665, found 420.0660.
4.2.6. ðSꢀax; Rpꢀl; SpꢀlÞ-Di-tricarbonyl[(1,2,3,4,5,6-g)-
(10,20,30,40,50,60-g)-2-methoxy-6-ethyl-20-
methoxymethoxymethylbiphenyl]chromium complex 8bb
1H NMR (500 MHz, CDCl3)
d
1.20 (3H, t,
J = 7.4 Hz), 2.25–2.33 (1H, m), 2.57–2.66 (1H, m), 3.46
(3H, s), 3.90 (3H, s), 4.38 (1H, d, J = 13.4 Hz), 4.81
(1H, d, J = 6.3 Hz), 4.85 (1H, d, J = 6.3 Hz), 4.92 (1H,
d, J = 6.4 Hz), 4.95, (1H, d, J = 13.4 Hz), 5.03 (1H, t,
J = 6.4 Hz), 5.20 (1H, d, J = 6.4 Hz), 5.38 (1H, d,
J = 6.4 Hz), 5.64–5.76 (3H, m); 13C NMR (125 MHz,
CDCl3) d 14.1, 29.7, 55.9, 65.7, 73.5, 83.5, 85.6, 87.9,
94.7, 95.4, 96.8. 99.1, 116.3, 126.5, 127.6, 128.5, 132.6,
138.3, 232.5, 233.4; IR (CHCl3) 3694, 2971, 2930, 2253,
1963, 1892, 1601, 1567, 1456 cmꢁ1; MS (relative inten-
sity) m/z 558 (M, +4), 530 (3), 474 (11), 446 (9), 360
(69), 338 (20), 278 (42), 263 (46), 224 (82), 209 (100);
HRMS calcd for C24H22O9Cr2: 558.0074, found
558.0070.
4.2.3. ðSꢀax; SpꢀlÞ-Tricarbonyl[(1,2,3,4,5,6-g)-2-
methoxymethoxymethyl-20-methoxy-60-
ethylbiphenyl]chromium complex 6bb
1H NMR (500 MHz, CDCl3) d 1.04 (3H, t, J = 7.5 Hz),
2.42–2.53 (2H, m), 3.21 (3H, s), 3.89 (3H, s), 4.00 (1H, d,
J = 12.7 Hz), 4.21 (1H, d, J = 12.7 Hz), 4.49 (1H, d,
J = 6.6 Hz), 4.59 (1H, d, J = 6.6 Hz), 5.08 (1H, t,
J = 6.1 Hz), 5.44 (1H, d, J = 6.1 Hz), 5.53 (1H, d,
J = 6.1 Hz), 5.62 (1H, t, J = 6.1 Hz), 6.82 (1H, d, J =
8.2 Hz), 6.90 (1H, d, J = 8.2 Hz), 7.32 (1H, t,
J = 8.2 Hz); 13C NMR (125 MHz, CDCl3) d 15.0, 26.7,
55.0, 55.2, 66.0, 86.6, 88.3, 95.2, 96.4, 98.3, 103.3, 108.6,
110.9, 120.9, 127.3, 129.8, 145.5, 154.9, 233.4; IR (CHCl3)
3694, 2967, 2923, 1966, 1891, 1605, 1576, 1464 cmꢁ1; MS
(relative intensity) m/z 422 (M, +3), 394 (2), 366 (5), 338
(63), 278 (100); HRMS calcd for C21H22O6Cr: 422.0821,
found 422.0823.
4.2.7. ðSꢀax; Spꢀl; SpꢀlÞ-Di-tricarbonyl[(1,2,3,4,5,6-g)-
(10,20,30,40,50,60-g)-2-methoxy-6-acetoxymethyl-20-
methylbiphenyl]chromium complex 8cc0
1H NMR (500 MHz, CDCl3) d 2.02 (3H, s), 2.14 (3H, s),
3.65 (3H, s), 4.95–5.10 (5H, m), 5.70–5.80 (4H, m); IR
(CHCl3) 2977, 2254, 1980, 1966, 1898, 1602 cmꢁ1; MS (rel-
ative intensity) m/z 542 (M, +4), 486 (6), 458 (34), 420 (3),
406 (7), 374 (100), 346 (16), 322 (52); HRMS calcd for
C23H18O9Cr2: 541.9761, found 541.9759.

684
K. Kamikawa et al. / Journal of Organometallic Chemistry 692 (2007) 678–684
(c) M.J. Morris, in: E.W. Abel, F.G.A. Stone, G. Wilkinson (Eds.),
Comprehensive Organometallic Chemistry II, vol. 5, Pergamon Press,
New York, 1995, pp. 501–504;
4.3. Oxidation reaction of the planar chiral biaryl chromium
complex 6ba
(d) N.A. Ustynyuk, Organomet. Chem. USSR 2 (1989) 43.
[2] (a) K.H. Do¨tz, N. Szesni, M. Nieger, K. Na¨ttinen, J. Organomet.
Chem. 671 (2003) 58;
Oxidation reaction of biaryl chromium complex 14 was
carried out according to the reported procedure [10].
(b) Y. Oprunenko, S. Malyugina, P. Nesterenko, D. Mityuk, O.
Malyshev, J. Organomet. Chem. 597 (2000) 42;
(c) D. Paetsch, K.H. Do¨tz, Tetrahedron Lett. 40 (1999) 487;
4.3.1. ðSꢀax; SpꢀlÞ-Tricarbonyl[(1,2,3,4,5,6-g)-2-formyl-20-
methoxy-60-ethylbiphenyl]chromium complex 14
(d) K.H. Do¨tz, C. Stinner, Tetrahedron: Asymmetry
1751;
8 (1997)
1H NMR (500 MHz, CDCl3) d 1.04 (3H, t, J = 7.6 Hz),
2.53–2.65 (2H, m), 3.88 (3H, s), 5.41 (1H, d, J = 6.4 Hz),
5.47 (1H, t, J = 6.4 Hz), 5.55 (1H, t, J = 6.4 Hz), 5.91
(1H, d, J = 6.4 Hz), 6.87 (1H, d, J = 8.0 Hz), 6.98 (1H, d,
J = 8.0 Hz), 7.38 (1H, t, J = 8.0 Hz), 9.40 (1H, s); 13C
NMR (125 MHz, C6D6) d 27.0, 30.2, 54.9, 87.9, 90.0,
92.4, 109.0, 121.5, 127.3, 127.9, 128.1, 128.6, 130.6, 176.3,
232.4; IR (CHCl3) 3160, 2257, 1980, 1913, 1802,
1599 cmꢁ1; MS (relative intensity) m/z 376 (M, +6), 292
(78), 193 (32), 58 (100); HRMS calcd for C19H16O5Cr:
376.0402, found 376.0400.
(e) Y.F. Oprunenko, S.G. Malyugina, Y.A. Ustynyuk, N.A.
Ustynyuk, D.N. Kravtsov, J. Organomet. Chem. 338 (1988)
357;
(f) E.P. Ku¨ndig, V. Desobry, C. Grivet, B. Rudolph, S.
Spichiger, Organometallics 6 (1987) 1173;
(g) R.U. Kriss, P.M. Treichel, J. Am. Chem. Soc. 108 (1986)
853.
[3] (a) J. Pan, J.W. Kampf, A.J. Ashe III, Organometallics 25 (2006)
197;
(b) Y.F. Oprunenko, J.A. Shaposhnikova, Y.A. Ustynyuk, Metal-
loorg. Khim. 4 (1991) 1377;
¨
(c) S.D. Cunningham, K. Ofele, B.R. Willeford, J. Am. Chem. Soc.
105 (1983) 3724;
(d) T.G. Traylor, M.J. Goldberg, Organometallics 6 (1987) 2531.
[4] (a) K. Kamikawa, T. Sakamoto, Y. Tanaka, M. Uemura, J. Org.
Chem. 68 (2003) 9356;
4.4. Stereoselective nucleophilic addition reaction
The stereoselective nucleophilic addition reaction to the
complex 15 was carried out according to the reported pro-
cedure [4a].
(b) K. Kamikawa, T. Sakamoto, M. Uemura, Synlett (2003)
516.
[5] Mobile chiral auxiliary in diene tricarbonyl complex see: Y. Takem-
oto, N. Yoshikawa, Y. Baba, C. Iwata, T. Tanaka, T. Ibuka, H.
Ohishi, J. Am. Chem. Soc. 121 (1999) 9143.
[6] M. Uemura, H. Nishimura, K. Kamikawa, M. Shiro, Inorg. Chim.
Acta 222 (1994) 63.
4.4.1. ðSꢀax; SpꢀlÞ-Tricarbonyl[(1,2,3,4,5,6-g)-2-hydroxyethyl-
20-methoxy-60-ethylbiphenyl]chromium complex 15
1H NMR (500 MHz, CDCl3) d 1.06 (3H, d, J = 6.4 Hz),
1.15 (3H, t, J = 7.7 Hz), 2.25 (1H, br), 2.41 (2H, dq,
J = 3.2, 7.7 Hz), 3.93 (3H, s), 4.39–4.44 (1H, m), 5.10
(1H, t, J = 6.5 Hz), 5.37 (1H, d, J = 6.5 Hz), 5.63 (1H, d,
J = 6.5 Hz), 5.67 (1H, t, J = 6.5 Hz), 6.83 (1H, d,
J = 8.2 Hz), 6.95 (1H, d, J = 8.2 Hz), 7.34 (1H, t,
J = 8.2 Hz); IR (CHCl3) 3360, 3000, 1964, 1887,
1561 cmꢁ1; MS (relative intensity) m/z 392 (M, +3), 336
(16), 308 (43), 290 (75), 275 (40), 256 (12), 238 (50), 223
(100); HRMS calcd for C20H20O5Cr: 392.0716, found
392.0717.
[7] (a) For representative references: C. Bolm, K. Muniz, Chem. Soc.
˜
Rev. 28 (1999) 51;
(b) S.E. Gibson, H. Ibrahim, Chem. Commun. (2002) 2465;
(c) J.P. Collman, L.S. Hegedus, J.R. Norton, R.G. Finke, in:
Principles and Applications of Organotransition Metal Chemistry,
University Science Books, Mill Valley, Calf, 1987, p. 921;
(d) S.G. Davies, T.M. McCarthy, in: G. Wilkinsons, P.G.A. Stone,
E.W. Abel (Eds.), Comprehensive Organometallic Chemistry II, vol.
12, Pergamon Press, Oxford, 1995;
(e) C. Mukai, W.J. Cho, I.J.M. KimKido, M. Hanaoka, Tetrahedron
47 (1991) 3007;
(f) C. Baldolli, P. Del Buttero, J. Chem. Soc., Chem. Commun.
(1991) 982;
(g) M. Uemura, R. Miyake, K. Nakayama, M. Shiro, Y. Hayashi, J.
Org. Chem. 58 (1993) 1238.
Acknowledgement
´
[8] (a) For some reviews: A. Solladie-Cavallo, in: L.S. Liebeskind (Ed.),
Advances in Metal-Organic Chemistry, vol. 1, JAI Press, Greenwich,
1989, p. 99;
(b) S.G. Davies, S.J. Coote, C.L. Goodfellow, in: L.S. Liebeskind
(Ed.), Advances in Metal-Organic Chemistry, vol. 2, JAI Press,
Greenwich, 1991, p. 1;
This work was supported by a Grant-in-Aid for Scien-
tific Research on Priority Areas (No. 14078101, Reaction
Control of Dynamic Complexes) from Ministry of Educa-
tion, Culture, Sports, Science and Technology, Japan.
(c) M. Uemura, in: L.S. Liebeskind (Ed.), Advances in Metal-Organic
Chemistry, vol. 2, JAI Press, Greenwich, 1991, p. 195;
(d) S.G. Davies, T. Donohoe, Synlett (1993) 323.
[9] K. Kamikawa, T. Watanabe, M. Uemura, J. Org. Chem. 61 (1996)
1375.
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