Asymmetric IrI-catalysed allylic alkylation of monosubstituted allylic acetates with phosphorus amidites as ligands

Article abstract of DOI:10.1002/ejoc.200390162

Monodentate phosphorus amidites derived from 2,2′-binaphthol and a variety of chiral amines were employed as ligands in Ir^I-catalysed allylic alkylations of unsymmetrically substituted allylic acetates. The enantio- and regioselectivities of these reactions were investigated. Phosphorus amidites of bulky secondary chiral amines induced enantioselectivities of up to 94% ee in reactions of linear substrates. Phosphorus amidites derived from chiral primary amines, which have not been previously employed in asymmetric catalysis, furnished improved regioselectivities. The use of LiCl as additive led to improved regio- and enantioselectivities. ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003).

Full text of DOI:10.1002/ejoc.200390162

FULL PAPER
I
Asymmetric Ir -Catalysed Allylic Alkylation Of Monosubstituted Allylic
Acetates With Phosphorus Amidites As Ligands
[a]
[a]
[a]
Björn Bartels, Cristina Garc ´ı a-Yebra, and Günter Helmchen*
Keywords: Iridium / Allylic substitution / Asymmetric catalysis / P ligands / Chirality
Monodentate phosphorus amidites derived from 2,2Ј-binaph-
amidites derived from chiral primary amines, which have not
been previously employed in asymmetric catalysis, furnished
improved regioselectivities. The use of LiCl as additive led
thol and a variety of chiral amines were employed as ligands
I
in Ir -catalysed allylic alkylations of unsymmetrically substi-
tuted allylic acetates. The enantio- and regioselectivities of to improved regio- and enantioselectivities.
these reactions were investigated. Phosphorus amidites of
bulky secondary chiral amines induced enantioselectivities
( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
of up to 94% ee in reactions of linear substrates. Phosphorus
Germany, 2003)
Introduction
Transition-metal-catalysed asymmetric allylic substitu-
tions are widely employed in organic synthesis.[1] Usually,
symmetrically substituted allylic derivatives are used as sub-
strates. Synthetically more easily accessible monosubsti-
tuted allylic substrates 1 or 2 (Scheme 1) are rarely em-
ployed because, in addition to enantioselectivity, regioselec-
tivity in favour of branched chiral products 3 must be
achieved. With palladium complexes as catalysts, linear
products are generally produced. Only very recently have
ligands been developed that give rise to the branched prod-
Scheme 1. General scheme for the metal-catalysed allylic substitu-
[
2]
ucts 3 in special cases (R ϭ CH and R ϭ aryl). With tion of monosubstituted allylic substrates
3
alkyl-substituted substrates synthetically useful results have
not been obtained so far. In contrast, Mo- or W-based cata-
lysts preferentially give rise to branched products. High
levels of reactivity and enantioselectivity were obtained
within the limits stated for Pd complexes.[ With Pd cata- enantiomerically enriched products 3 via double inversion
lysts reactions proceed via π-allyl complexes which can iso- processes. Because of this, these metal ions appeared not to
merize via π-σ-π rearrangement or related processes so that be suitable for asymmetric synthesis. Surprisingly, asymmet-
branched and linear substrates yield the same products. ric synthesis was recently nevertheless accomplished with
3]
[
4]
[7]
Memory effects are known but are usually small.
Memory effects for Mo- and W-catalyst are strongly de-
pendent on the auxiliary ligand, nucleophile and substrate, lysts prepared by combining [IrCl(COD)]2 with a π-ac-
and are poorely understood.[5]
ceptor ligand, usually triphenylphosphite, regioselectively
Substitutions catalysed by Rh, Fe or Ru complexes pro- furnish branched products 3 from both aryl- and alkyl-sub-
symmetrically substituted 1,3-diarylallyl derivatives.
I
Ir -catalysed allylic substitutions, carried out with cata-
[
8]
ceed with a high degree of conservation of enantiomeric stituted allylic substrates (cf. Scheme 2). Ir-based catalysis
excess (cee). Intermediates of these reactions are σ- or is of particular interest because of its broad scope con-
π-allyl complexes which isomerize slowly compared to cerning allylic substrates. Since 1997 we and others have
allyl)Pd complexes.[ As a consequence, enantiomerically studied enantioselective Ir -catalysed allylic substitutions
6]
I
(
[
9]
enriched substrates 1, even with achiral ligands, yield using bidentate chiral phosphinooxazolines and chiral
[
10]
phosphites and phosphorus amidites as ligands. We have
recently published a full account of our studies concerning
[
a]
Organisch-chemisches Institut der Universität Heidelberg,
Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
Fax: (internat.) ϩ49-(0)6221/544-205
I
the various factors affecting the steric course of the Ir -cata-
E-mail: g.helmchen@urz.uni-heidelberg.de
lysed allylic substitution including characterisation of
Eur. J. Org. Chem. 2003, 1097Ϫ1103  2003 WILEY-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim 1434Ϫ193X/03/0306Ϫ1097 $ 20.00ϩ.50/0
1097

B. Bartels, C. Garc ´ı a-Yebra, G. Helmchen
FULL PAPER
III
(
allyl)Ir complexes related to the proposed intermediate Use of Phosphorus Amidites Derived from Secondary
[
11]
species.
Amines as Ligands
In the first set of experiments phosphorus amidites of
widely differing types were tested as ligands (Table 1):
[
12]
[13]
L1,
L2,
known from the work of Feringa, and L3,
[
14]
prepared by standard procedures.
Table 1. Allylic substitutions according to Scheme 2 with substrates
(
rac)-1a and 2a using diverse chiral phosphorus amidites as li-
[a]
gands
I
Scheme 2. Substrates and typical conditions employed in the Ir -
catalysed allylic alkylations
According to the previous work, the following aspects of
I
the Ir -catalysed allylic alkylations are important: (a) There
Entry Sub- Ligand
strate
Temp. Time Yield Ratio[b] ee [%][b]
is a distinct memory effect with respect to regioselectivity,
i.e., preference for the branched product 3 is higher with
the branched substrate 1 than with the linear substrate 2.
[°C]
[h]
[%]
3:4
(Conf.)
1
2
3
4
5
6
1a
1a
1a
2a
2a
2a
(aR)-L1 25
3
5
72
3
96
96
92
17
31
54
34
26
98:2
84:16
96:4
95:5
21:79
39:61
69 (R)
5 (R)
9 (R)
43 (R)
8 (R)
7 (S)
(b) Similarly, substitution reactions with enantiomerically
(R,R)-L2 50
(S)-L3 [ 25
(aR)-L1 25
c]
enriched acetates 1 catalysed by complexes containing achi-
ral ligands proceed with partial conservation of enantio-
meric purity. Because of this, a high level of enantioselectivity
with a branched racemic substrate requires conditions that
promote isomerisation at the level of the substrates or inter-
(R,R)-L2 50
(S)-L3[
c]
50
[
a]
All reactions were carried out in THF as solvent at a 0.5 mmol
Me)
mol % of [IrCl(COD)]
2
and 4 mol % of the ligand. [ Determined
mediates of the reaction. (c) It was found that phosphorus scale [0.125 ] of allylic substrate with 2 equiv. of NaCH(CO
2
2
,
b]
2
amidite and, less effectively, phosphite ligands promote iso-
merization of the intermediates. Furthermore, addition of
LiCl gave rise to enhanced erosion of enantiomeric purity
[c]
by HPLC. Mixture of diastereomers (2.5:1); for details see Exp.
Sect.
when enantiomerically pure acetates 1 were used as sub-
The ligand L1, derived from 2,2Ј-binaphthol (BINOL),
III
strates. (d) Intermediate octahedral Ir complexes have gave the best results. This ligand was found to promote
III
been proposed to contain monodentate phosphorus and π- particularly fast isomerization of isomeric (allyl)Ir com-
allyl ligands in mutual cis disposition due to the strong plexes and, therefore, enantio- and regioselectivities for
trans influence of these ligands. (e) Finally, it was demon- both branched and linear substrates are similar (Table 1,
I
strated that the Ir -catalysed allylic alkylation proceeds via entries 1 and 4). Based on these results, work was concen-
a double inversion process.[
11]
trated on phosphorus amidites derived from BINOL using
[
12b,15]
[16]
Induced by the favourable properties of phosphorus ami- the readily available, known compounds L4,
dites as ligands, we have carefully investigated their use in L6,
L5,
[
15b,16]
[17]
and L7
as ligands (Figure 1). The results
asymmetric allylic substitutions. Here we report results ob- obtained in alkylations of substrates (rac)-1a and 2a are
tained with a variety of chiral phosphorus amidites. Phos- described in Table 2.
phorus amidites are usually derived from secondary amines.
In addition, we have investigated less bulky phosphorus am-
idites of primary amines.
Results and Discussion
In the previous studies, tests of substrates with various
I
leaving groups showed that acetates are best suited for Ir - Figure 1. Some phosphorus amidite ligands derived from second-
catalyzed allylic substitutions.[ Furthermore, aryl-substi-
tuted allylic derivatives invariably gave superior results. In
order to gain a realistic assessment of the results, reactions
11]
ary amines
Reaction rates were distinctly lower with the bulky li-
with the alkyl-substituted compounds 1a and 2a (Scheme 2) gands L4ϪL7 than with the comparatively small ligand L1.
were thoroughly studied and considered representative. Regioselectivity was generally higher for the branched sub-
Further studies using substrates 1bϪf and 2bϪe were then strate 1a than the linear substrate 2a. However, while the
carried out in order to assess the scope of the method.
difference was small with ligand L1, it was very pronounced
1098
Eur. J. Org. Chem. 2003, 1097Ϫ1103

I
Asymmetric Ir -Catalysed Allylic Alkylation of Monosubstituted Allylic Acetates
FULL PAPER
Table 2. Phosphorus amidites derived from secondary amines in Use of Phosphorus Amidites Derived from Primary Amines
I
[a]
Ir -catalyzed allylic alkylation of substrates (rac)-1a and 2a
as Ligands
Temp. Time Yield Ratio[b] ee [%] [b]
The ligands L8 to L13 were synthesized by the standard
procedure (Scheme 3) involving treatment of BINOL with
phosphorus trichloride and further coupling of the product
with the primary amine in the presence of two equivalents
Entry Sub- Ligand
strate
[°C]
[h]
[%]
3:4
(Conf.)
1
2
3
4
5
6
7
8
9
0
1a
1a
1a
1a
1a
2a
2a
2a
2a
2a
(aR)-L1
(aR)-L4
25
50
3
18
18
18
48
3
96
96
96
72
92
69
85
10
97
54
92
49
91
73
98:2
69 (R)
21 (S)
27 (S)
24 (R)
7 (R)
43 (R)
12 (S)
23 (S)
77 (R)
61 (R)
85:15
86:14
89:11
89:11
95:5
28:72
30:70
53:47
53:47
of NEt . Ligands L8ϪL13 were obtained in 35Ϫ69% yield.
3
(aR,S,S)-L5 50
(aS,S,S)-L6 25
The results obtained with the new ligands in catalysis are
summarised in Table 3. As anticipated, significant improve-
ment, compared to the results obtained with ligands
L4ϪL6, with respect to reactivity as well as regioselectivity
was obtained. The enantioselectivity was almost the same
as that achieved with L1 (cf. entry 1 of Table 2 with entry
(S,S)-L7
(aR)-L1
(aR)-L4
25
25
50
(aR,S,S)-L5 50
(aS,S,S)-L6 50
1
(S,S)-L7
50
3
of Table 3) in the case of substrate 1a. With substrate 2a
All reactions were carried out in THF at a 0.5 mmol scale [0.125 the degree of enantioselectivity was low (19Ϫ57% ee).
] with 2 equiv. of NaCH(CO Me) , 2 mol % [IrCl(COD)] and 4
mol % of the ligand. Determined by HPLC.
[
a]

2
2
2
[
b]
Table 3. Phosphorus amidites derived from primary amines as li-
I
gands in Ir -catalyzed allylic alkylation of substrates (rac)-1a and
a]
2
a [
with L4ϪL7. There is no apparent trend with respect to
enantioselectivity. Ligand L1 performed best with the
branched substrate (Table 2, entry 1), ligand L6 gave an
even better result with the linear substrate (entry 9), while
the other bulky ligands L4 and L5 gave rise to low enanti-
oselectivity (entries 7, 8). There is also no visible trend con-
cerning the configurational course of the reaction. Even li-
gands L1 and L4, with only a stereogenic axis, yield prod-
ucts with the opposite configuration (cf. entries 1, 2 and 6,
Temp. Time Yield Ratio[b] ee [%] [b]
Entry Sub- Ligand
strate
[°C]
[h]
[%]
3:4
(Conf.)
1
2
3
4
5
6
7
8
9
0
1a
1a
1a
1a
1a
1a
2a
2a
2a
2a
2a
2a
(aR,S)-L8 25
3
5
3
18
18
18
3
98
96
65
60
98
94
56
67
15
40
81
53
99:1
96:4
99:1
99:1
98:2
98:2
83:17
88:12
67:33
67:33
90:10
72:28
64 (R)
27 (S)
68 (R)
18 (S)
31 (R)
19 (S)
57 (R)
38 (S)
35 (R)
19 (S)
24 (R)
39 (S)
(aS,S)-L9 25
(aR,S)-L10 25
(aS,S)-L11 25
(aR,S)-L12 25
(aS,S)-L13 25
(aR,S)-L8 25
(aS,S)-L9 25
(aR,S)-L10 25
(aS,S)-L11 25
(aR,S)-L12 25
(aS,S)-L13 25
7). Similarly, the diastereomeric ligands L5 and L6 show
5
widely differing influences without apparent pattern. Li-
gand L7, with only a stereogenic center, gave widely dif-
fering enantioselectivities for substrates 1a and 2a so that 11
the relative influences of the BINOL moiety and the amine 12
18
18
18
18
1
moiety are not apparent.
[
a]
All reactions were carried out in THF at a 0.5 mmol scale [0.125
] with 2 equiv. of NaCH(CO Me) , 2 mol % [IrCl(COD)] and 4
In view of the low reactivity found for ligands with bulky
substituents at nitrogen, it was of interest to test phos-
phorus amidites derived from chiral primary amines in the
allylic alkylation. It was hoped that enhanced reactivity
might not only be due to the reduced steric bulk but also
due to favorable hydrogen bonds between the NH group

2
2
2
[b]
mol % of the ligand. Determined by HPLC.
Scope with Respect to Substrate
According to the results presented above, L1 is the most
and the substrate. In previous work, we have obtained excel- suitable ligand for branched acetates (1), while the phos-
lent results with such ligands in asymmetric hydrogena- phorus amidite L6 gives the best enantioselectivities but low
[
18]
tions.
regioselectivity for linear acetates (2).
Scheme 3. Phosphorus amidites derived from primary amines
Eur. J. Org. Chem. 2003, 1097Ϫ1103
1099

B. Bartels, C. Garc ´ı a-Yebra, G. Helmchen
Table 4. Allylic substitutions according to Scheme 2 using L6 as ligand: variation of linear substrates 2 and effect of additives[a]
FULL PAPER
Entry
R, Substrate
Additive[b]
Temp.
°C]
Time
Yield
[%]
Ratio[c]
3:4
ee [%][d]
(Conf.)
[
1
2
3
4
5
6
7
8
9
CH
CH
2
CH
CH
2
Ph, 2a
Ph, 2a
Ϫ
LiCl
Ϫ
LiCl
Ϫ
LiCl
Ϫ
LiCl
Ϫ
LiCl
50
50
25
25
25
25
25
25
50
50
4 d
4 d
18 h
18 h
3 d
3 d
4 d
4 d
3 d
3 d
91
84
41
98
85
96
25
56
88
79
53:47
65:35
70:30
91:9
58:42
75:25
30:70
55:45
50:50
65:35
77 (R)
92 (R)
70 (R)
86 (R)
56 (R)
82 (R)
78 (R)
94 (R)
77 (R)
83 (R)
2
2
Ph, 2b
Ph, 2b
Me, 2c
Me, 2c
iPr, 2d
iPr, 2d
CH
CH
2
CH
CH
2
OMOM, 2e
OMOM, 2e
10
2
2
[
a]
All reactions were carried out in THF at a 0.5 mmol scale [0.125 ] with 2 equiv. NaCH(CO
2
Me)
2
, 2 mol % [IrCl(COD)]
2
and 4 mol %
I
[b]
(
(
aS,S,S)-L6; a general procedure for the Ir -catalyzed allylic alkylation is described in the Exp. Sect. (see below).
One equivalent
relative to substrate) of additive was added before addition of the nucleophile. [c] Determined by GC/MS. Determined by HPLC or GC.
[d]
L1 has previously been tested as chiral ligand in the IrI-
catalyzed allylic alkylation of the branched aryl- and al-
kylallyl acetates 1aϪf (Scheme 2), giving rise to high values
of regioselectivity (94Ϫ99%) and enantioselectivities of up
Experimental Section
General: All reactions were carried out using dry solvents under an
argon atmosphere. TLC: Macherey & Nagel Polygram Sil G/UV
to 86% ee (with 1a) for the formation of branched products precoated sheets, treatment with I2 or aqueous KMnO4 solution
[
11]
3.
In addition, ligand L6 has now been tested in allylic for visualization of spots. Column chromatography: Fluka silica
1
alkylations of the linear acetates 2aϪe. The results are dis- gel, grade 60 (0.04Ϫ0.063 mm) or aluminum oxide, activity IV. H,
played in Table 4.
Enantiomeric excesses of between 56 and 78% ee,
achieved using the standard reaction conditions, were
promising (Table 4). Considering that halide ions can accel-
erate isomerization of allylic intermediates via σ-allyl com-
1
3
31
C and P NMR spectra were recorded on Bruker DRX 300 or
1
DRX 500 instruments. H NMR chemical shifts are relative to re-
sidual non-deuterated solvent in CDCl
[D
8
3
(δ ϭ 7.26 ppm) or
]THF (δ ϭ 1.72, 3.57 ppm). C NMR shifts are quoted relative
to the solvents CDCl (δ ϭ 77.0 ppm) and [D ]THF (δ ϭ 25.20,
7.20 ppm) and P NMR shifts are relative to 85% H PO (δ ϭ
1
3
3
8
31
6
3
4
[
11,19]
plexes,
LiCl was added to the reaction mixtures. In-
0.00 ppm). MS: JEOL, JMS-700. FAB: JEOL, JMS-700; matrix:
deed, addition of one equivalent of LiCl led to marked im-
4-nitrobenzyl alcohol (NBA) or 4-nitrophenyl octyl ether (NPOE).
provement, up to 82Ϫ94% ee. This additive also positively Optical rotation: PerkinϪElmer P 241. GC: Hewlett Packard HP
affected the regioselectivity of the process. Nevertheless, the 5890 with Chiraldex γ-CD TA column (30 m ϫ 0.25 mm). HPLC:
regioselectivity of the substitution still has to be consider- Hewlett Packard HP 1090 with DAICEL Chiralcel ODH column
(
25 cm ϫ 0.46 cm) in combination with DAICEL Chiralcel ODH
ably improved, except in the case where R is Ph (2b).
precolumn (5 cm ϫ 0.46 cm). Elemental analyses: Microanalytical
Laboratory of the Organisch-Chemisches Institut, Universität Hei-
[12]
[13]
[12b,15]
[16]
delberg. The ligands L1, L2, L4,
(R,S,S)-L5, (S,S,S)-
L6,[
15b,16]
and L7 were prepared according to published proced-
[17]
Conclusion
ures. Allylic esters were prepared by reaction of the corresponding
alcohols with acetic anhydride {1a,
[20]
[11,21]
[22]
(E)-2a,
(E)-2b,
(E)-
[23]
[11]
[11]
[11,24]
[22]
[6c,23]
A set of 13 chiral phosphorus amidite ligands has been 2c, (E)-2d and (E)-2e }. Compounds 3a
3b, 3c,
tested in asymmetric Ir-catalyzed allylic alkylations of al- 3d[ and 3e
25]
[11,26]
have been described and characterised previously.
lylic substrates with widely differing substituents. The com-
paratively small ligand L1 derived from BINOL and di-
methylamine was optimal with respect to reactivity and re- Synthesis of L3: P(NMe ) (690 µL, 3.10 mmol) was added drop-
Synthesis of Phosphorus Amidites
2
3
gioselectivity. The particularly bulky ligand L6, derived wise to a suspension of (S)-N-tosylvalinol (975 mg, 3.10 mmol) and
Cl (7 mg, 0.10 mmol) in toluene (10 mL). The mixture was
from (aS)-BINOL and (S,S)-bis(1-phenylethyl)amine, gave NH
4
stirred for 18 h at 80 °C, then taken to room temperature and con-
centrated in vacuo to give a colourless oil, which gave colourless
rise to the highest enantioselectivity but relatively low de-
grees of regioselectivity and reactivity with linear allyl acet-
ates. Improved results were obtained with LiCl as additive
and with phosphorus amidites derived from secondary
amines. With these ligands of a new type both reactivity
and regioselectivity were considerably improved, although
enantioselectivities were lower than with L6. Further re-
search is required in order to fully explore the potential of
chiral phosphorus amidites derived from primary amines.
crystals of L3 (2.5:1 mixture of diastereomers) upon treatment with
1
CH
2
Cl
2
. Yield: 640 mg (63%). H NMR (500.13 MHz, CDCl
3
, 25
°
C, values marked [*] belong to the minor diastereomer): δ ϭ 0.46
3
3
(
d,
J
H,H ϭ 7.3 Hz, 3 H, Me
2
CH), 0.74 (d,
JH,H ϭ 6.7 Hz, 3 H,
3
3
Me
6
2
CH), 0.93 (d, JH,H ϭ 6.7 Hz, 3 H, Me CH)*, 1.04 (d, JH,H
.7 Hz, 3 H, Me
2
ϭ
4
3
2
CH)*, 1.95 (qqd,
J
H,P ϭ 3.0,
JH,H ϭ 6.7,
3
JH,H ϭ 7.3 Hz, 1 H, Me CH), 2.31Ϫ2.40 (m, 1 H, Me CH)*, 2.42
2
2
3
(s, 3 H, MeC
6
H
4
6 4
), 2.43 (s, 3 H, MeC H )*, 2.64 (d, JH,P ϭ 8.5 Hz,
1100
Eur. J. Org. Chem. 2003, 1097Ϫ1103

I
Asymmetric Ir -Catalysed Allylic Alkylation of Monosubstituted Allylic Acetates
FULL PAPER
6
H, NMe
2
), 2.76 (d, 3
J
H,P ϭ 9.8 Hz, 6 H, NMe
2
)*, 2.95 (dddd, crystallized from CH
2
Cl
2
and further subjected to MPLC on an
3
3
3
3
J
H,P ϭ 1.8,
Me
.97Ϫ4.04 (m, 2 H, Me
ddd, 3 H,H ϭ 6.7, 3 H,P ϭ 6.7, 2
JH,H ϭ 6.7,
JH,H ϭ 6.7,
JH,H ϭ 6.7 Hz, 1 H,
aluminum oxide column [activity IV; 3 cm ϫ 28 cm, flow 50 mL/
2
CHCHN)*, 3.73Ϫ3.80 (m, 1 H, Me
CHCHN and Me CHCHCH
H,H ϭ 9.2 Hz, 1 H, Me
2
CHCHCH
2
O)*, min; eluent: petroleum ether/ethyl acetate (9:1)], previously deactiv-
(1 mL). Yield: 69% (1.04 g), colourless
3
(
2
2
2
O), 4.16 ated by injection of NEt
3
23
1
J
J
J
2
CHCH-
D 3
crystalline solid. [α] ϭ Ϫ264.1 (c ϭ 0.14, CHCl ). H NMR
3
2
3
CH
CH
8
7
(
2
O)*, 4.30 (dd, JH,H ϭ 6.7, JH,H ϭ 9.2 Hz, 1 H, Me
2
CHCH- (500.13 MHz, [D
8
]THF, 25 °C): δ ϭ 1.45 (d, JH,H ϭ 6.7 Hz, 3 H,
O), 7.28 (d, 3
J
H,H ϭ 8.5 Hz, 2 H, m-C
)*, 7.80 (d, 3
H,H ϭ 8.5 Hz, 2 H, o-C
H,H ϭ 8.5 Hz, 2 H, o-C
75.47 MHz, [D ]THF, values marked [*] belong to the minor dias-
tereomer): δ ϭ 14.9 (s, Me
H
4
), 7.31 (d,
3
J
ϭ
CH
2
2
6
H,H
3 3
), 4.40Ϫ4.50 (m, 1 H, CHCH ), 5.09 (d, JH,P ϭ 10.7 Hz, 1 H,
3
.5 Hz, 2 H, m-C
6
H
4
J
6 4
H )*, NH), 6.80 (d, JH,H ϭ 8.7 Hz, 1 H, arom. H), 7.17Ϫ7.39 (m, 11 H,
3
13
1
3
3
.82 (d,
J
6
H
4
) ppm. C{ H} NMR
arom. H), 7.49 (d, JH,H ϭ 8.7 Hz, 1 H, arom. H), 7.82 (d, JH,H ϭ
3
8
8.7 Hz, 1 H, arom. H), 7.89 (d, JH,H ϭ 9.0 Hz, 1 H, arom. H),
3
3
2
CH), 15.0 (s, Me
2
CH), 18.70 (s,
7.91 (d,
J
H,H ϭ 9.0 Hz, 1 H, arom. H), 7.98 (d,
J
H,H ϭ 9.0 Hz,
]THF, 25
C,P ϭ 26.8 Hz,
), 122.7, 123.7 (both s, binaphthyl-CH), 124.2 (d, JC,P
CH), 37.0 (d, 2JC,P ϭ 20.1 Hz, NMe
), 63.4 1 H, arom. H) ppm. C{ H} NMR (125.77 MHz, [D
C,P ϭ 11.6 Hz, °C): δ ϭ 26.0 (d,
), 128.6 (2d, CHCH
13
1
MeC
(
6
H
4
), 21.4 (s, Me
2
2
8
d, 2JC,P ϭ 3.5 Hz, Me
Me CHCHCH
C,P ϭ 6.2 Hz, o-C
41.5 (s, ipso-C
202.47 MHz, CDCl
FAB): m/z (%) ϭ 331 (69) [M ϩ 1], 286 (81) [M Ϫ NMe
CHCHN), 67.7 (d,
2
J
3
2
2
3
JC,P ϭ 7.0 Hz, CH ), 51.8 (d, J
4
2
2
O), 127.9 (2d, JC,P ϭ 2.8 Hz, o-C
)*, 130.1 (s, m-C ), 130.2 (s, m-C
), 143.7 (s, p-C
6
H
4
3
ϭ
4
J
6
H
4
6
H
4
6
H
4
)*,
2.4 Hz, binaphthyl-C), 125.0 (d, JC,P ϭ 4.7 Hz, binaphthyl-C),
125.2, 125.4, 126.6, 126.7 (all s, binaphthyl-CH), 127.1 (s, Ph-CH),
31
1
1
(
(
6
H
4
6 4
H ) ppm. P{ H} NMR
3
, 25 °C): δ ϭ 143.45 (s), 157.47 (s) ppm. MS 127.4 (s, Ph-CH), 127.4, 127.6 (both s, binaphthyl-CH), 129.0 (2s,
ϩ ϩ
2
]. Ph and binaphthyl-CH), 129.1, 130.0, 130.9 (all s, binaphthyl-CH),
ϩ
3
HRMS (FAB): M ϭ C14
31.1270.
H
24
O
3
N
2
SP calcd. 331.1245; found
132.0, 132.4, 133.7, 133.8 (all s, binaphthyl-C), 147.8 (d,
C,P
J ϭ
3
1.9 Hz, Ph-C), 149.4 (d, JC,P ϭ 4.7 Hz, binaphthyl-C), 150.8 (s, bi-
3
1
1
naphthyl-C) ppm. P{ H} NMR (202.47 MHz, [D
8
]THF, 25 °C):
ϩ
General Procedure for the Synthesis of Ligands L8؊L13: The reac-
tions were carried out in the vessel shown in Figure 2. In flask A,
a solution of PCl
treated with triethylamine (975 µL, 7.00 mmol) and then 2,2Ј-bi-
naphthol (1.00 g, 3.50 mmol). The mixture was stirred for 6 h at
room temperature and then filtered into flask B. After washing the
precipitate in flask A once with toluene (10 mL), the combined
filtrates were cooled (0 °C). Triethylamine (975 µL, 7.00 mmol) and
the corresponding primary amine (3.50 mmol) were added, and the
mixture was stirred for 18 h at room temperature, after which it
δ ϭ 154.42 (s) ppm. MS (EI): m/z (%) ϭ 435 (85) [M ], 315 (63)
ϩ
ϩ
[
M
Ϫ NHCHCH
3
Ph], 268 (48) [M Ϫ NHCHCH
HRMS (EI) M ϭ C28 NP, calcd. 435.1388; found 435.1375.
22NO P (435.46): C 77.23, H 5.09, N 3.22, P 7.11; found C
6.97, H 5.35, N 3.31, P 6.86.
3
Ph Ϫ PO].
3
(305 µL, 3.50 mmol) in toluene (15 mL) was
ϩ
22 2
H O
C
7
28
H
2
Synthesis of L9: Ligand L9 was prepared according to the general
procedure from (aS)-BINOL (1.00 g, 3.50 mmol) and (S)-phenyle-
thylamine (450 µL, 424 mg, 3.50 mmol). The crude product was
purified by MPLC, first on a silica gel 60 column [3 cm ϫ 25 cm,
flow 70 mL/min; eluent: petroleum ether/ethyl acetate (9:1)] previ-
was filtered under argon, in order to remove NH
trated in vacuo. Products were purified by MPLC.
4
Cl, and concen-
3
ously deactivated with NEt (1 mL). The product obtained was
subjected to a second MPLC purification on an aluminum oxide
column [activity IV; 3 cm ϫ 28 cm, flow 50 mL/min; eluent: petro-
leum ether/ethyl acetate (9:1)], previously deactivated with NEt
3
2
3
(
1 mL). Yield: 35% (528 mg), colorless crystalline solid. [α]
D
ϭ
1
ϩ252.5 (c ϭ 0.13, CHCl
3
). H NMR (500.13 MHz, [D
C): δ ϭ 1.46 (d, JH,H ϭ 6.7 Hz, 3 H, CH ), 4.43Ϫ4.53 (m, 1 H,
CHCH ), 5.09 (dd, J ϭ 9.4, J ϭ 9.7 Hz, 1 H, NH), 7.15Ϫ7.39 (m,
2 H, arom. H), 7.49 (d, JH,H ϭ 8.7 Hz, 1 H, arom. H), 7.82 (d,
8
]THF, 25
3
°
3
3
3
1
3
3
J
H,H ϭ 8.7 Hz, 1 H, arom. H), 7.90 (d, JH,H ϭ 9.0 Hz, 1 H, arom.
3
3
H), 7.92 (d,
.0 Hz, 1 H, arom. H) ppm.
]THF, 25 °C): δ ϭ 27.1 (d, 3JC,P ϭ 3.8 Hz, CH
C,P ϭ 21.7 Hz, CHCH ), 122.8, 123.6 (both s, binaphthyl-CH),
24.0 (d, JC,P ϭ 2.4 Hz, binaphthyl-C), 125.0 (d, JC,P ϭ 5.2 Hz, bi-
H,H
JH,H ϭ 9.4 Hz, 1 H, arom. H), 7.98 (d, J ϭ
1
3
1
9
C{ H} NMR (125.77 MHz,
), 51.8 (d,
[
D
8
3
2
J
3
1
naphthyl-C), 125.2, 125.4, 126.6 (all s, binaphthyl-CH), 126.7 (s,
binaphthyl-CH), 126.8, 127.2 (both s, Ph-CH), 127.5, 127.6 (both
s, binaphthyl-CH), 128.9 (s, Ph-CH), 129.1, 129.2, 130.2, 130.9 (all
s, binaphthyl-CH), 131.9, 132.5, 133.8, 133.8 (all s, binaphthyl-C),
147.5 (d, JC,P ϭ 4.3 Hz, Ph-C), 149.6 (d, JC,P ϭ 5.2 Hz, binaphthyl-
Figure 2. Two-flask system for isothermal addition of sensitive
[
27]
compounds.
The system consists of two flasks, A and B, con-
3
1
1
nected by a capillary glass tube, provided with a sintered glass filter
plate, and a wide-bore tube C containing a stopcock. Flask A is
connected via D to an inert gas line and flask B through E to a
bubbler filled with paraffin oil. Initially, stopcock C is open in or-
der to provide equal pressure in flasks A and B. In flask A one of
the reagents is prepared and transferred into flask B by closing
stopcock C.
C), 150.8 (s, binaphthyl-C) ppm. P{ H} NMR (202.47 MHz,
[D ]THF, 25 °C): δ ϭ 152.39 (s) ppm. MS (EI): m/z (%) ϭ 435 (79)
8
ϩ
ϩ
ϩ
[
M ], 315 (66) [M
NHCHCH Ph Ϫ PO]. HMS (EI) M ϭ C28
435.1388; found 435.1378. C28 22NO P (435.46): C 77.23, H 5.09,
Ϫ
NHCHCH
3
Ph], 268 (46) [M
Ϫ
ϩ
3
22 2
H O NP calcd.
H
2
N 3.22, P 7.11; found C 77.14, H 5.23, N 3.36, P 6.86.
Synthesis of L10: Ligand L10 was prepared according to the gen-
eral procedure from (aR)-BINOL (1.00 g, 3.50 mmol) and (S)-1-(2-
naphthyl)ethylamine (600 mg, 3.50 mmol). The crude product was
purified twice by MPLC on a silica gel 60 column [3 cm ϫ 25 cm,
flow 70 mL/min; eluent: petroleum ether/ethyl acetate (9:1)] previ-
Synthesis of L8: Ligand L8 was prepared according to the general
procedure from (aR)-BINOL (1.00 g, 3.50 mmol) and (S)-phenyle-
thylamine (450 µL, 424 mg, 3.50 mmol). The crude product was
Eur. J. Org. Chem. 2003, 1097Ϫ1103
1101

B. Bartels, C. Garc ´ı a-Yebra, G. Helmchen
FULL PAPER
ously deactivated with NEt
3
(1 mL). Yield: 40% (679 mg), colorless Me
2
CH), 3.69 (ddd, 3
J
H,H ϭ 6.4, 3
J
H,H ϭ 11.7, 3
J
H,P ϭ 11.7 Hz,
crystals. [α]2
0
ϭ Ϫ203.71 (c ϭ 0.17, CHCl
).
1
H
NMR
1 H, CHCO Me), 3.75 (s, 3 H, CO
Me), 4.91 (d, JH,P ϭ 11.7 Hz,
2
D
3
2
2
3
3
3
(
500.13 MHz, CDCl
CH H,P ϭ 10.0 Hz, 1 H, NH), 4.66Ϫ4.78 (m, 1 H,
), 3.54 (d, 2
CHCH
H, arom. H), 7.36 (d, JH,H ϭ 8.7 Hz, 1 H, arom. H), 7.37Ϫ7.44
3
, 25 °C): δ ϭ 1.60 (d, JH,H ϭ 7.35 Hz, 3 H, 1 H, NH), 7.21 (d, JH,H ϭ 7.0 Hz, 1 H, arom. H), 7.23 (d, JH,H ϭ
3
J
7.0 Hz, 1 H, arom. H), 7.30Ϫ7.36 (m, 3 H, arom. H), 7.37 (d,
3
3
3
3
), 6.85 (d, JH,H ϭ 8.6 Hz, 1 H, arom. H), 7.20Ϫ7.30 (m,
JH,H ϭ 7.0 Hz, 1 H, arom. H), 7.39 (d, JH,H ϭ 7.0 Hz, 1 H, arom.
3
3
2
H), 7.50 (d,
J
H,H ϭ 8.7 Hz, 1 H, arom. H), 7.91Ϫ7.95 (m, 2 H,
3
3
3
(
8
7
m, 3 H, arom. H), 7.44Ϫ7.51 (m, 3 H, arom. H), 7.55 (d, JH,H
.7 Hz, 1 H, arom. H), 7.73 (d, 3
H,H ϭ 8.7 Hz, 2 H, arom. H),
.82Ϫ7.93 (m, 6 H, arom. H), 7.95 (d, JH,H ϭ 9.4 Hz, 1 H, arom.
ϭ
arom. H), 7.97 (d, JH,H ϭ 8.7 Hz, 1 H, arom. H), 7.99 (d, JH,H ϭ
13
1
J
8.7 Hz, 1 H, arom. H) ppm.
[D ]THF, 25 °C): δ ϭ 18.1 (s, Me
C,P ϭ 6.0 Hz, Me CH), 51.8 (s, CO
Me), 122.6, 124.0 (both arom. CH), 124.2 (s, arom. C),
C{ H} NMR (125.77 MHz,
3
8
2
CH), 19.5 (s, Me CH), 33.0 (d,
2
13
1
3
2
H) ppm. C{ H} NMR (125.77 MHz, CDCl
3
, 25 °C): δ ϭ 25.9 (d,
J
2
2
Me), 60.6 (d, JC,P ϭ 28.7 Hz,
3
2
JC,P ϭ 7.5 Hz, CH
3
), 51.4 (d, JC,P ϭ 26.4 Hz, CHCH ), 121.8 (d,
3
CHCO
2
J
J
C,P ϭ 2.0 Hz, binaphthyl-CH), 122.5 (s, binaphthyl-CH), 123.6 (d,
C,P ϭ 1.9 Hz, binaphthyl-C), 124.1 (d, JC,P ϭ 4.7 Hz, binaphthyl-
125.1 (d, JC,P ϭ 4.7 Hz, arom. C), 125.3, 125.5, 126.6, 126.8, 127.4,
127.7, 129.1, 129.2, 130.1, 130.9 (all s, arom. CH), 132.2, 132.5,
C), 124.2, 124.7, 124.8, 124.9, 125.8, 126.0, 126.1, 126.2, 126.8, 133.7, 133.8 (all s, arom. C), 149.1 (d, JC,P ϭ 4.7 Hz, arom. C),
3
1
26.9, 127.7, 127.9, 128.2, 128.3, 128.3, 129.3, 130.2 (all s, aromatic-
CH), 130.9, 131.4, 132.7, 132.75, 132.8, 133.4 (all s, aromatic-C),
43.6 (d, JC,P ϭ 1.9 Hz, naphthyl-C), 147.8 (d, JC,P ϭ 2.1 Hz, bi-
150.5 (s, arom. C), 174.0 (d,
J
C,P ϭ 2.8 Hz, COOMe) ppm.
3
1
1
P{ H} NMR (202.47 MHz, [D
8
]THF, 25 °C): δ ϭ 155.09 (s) ppm.
ϩ
ϩ
1
MS (EI): m/z (%) ϭ 445 (38) [M ], 402 (73) [M Ϫ CH(CH
3
)
2
],
],
ϭ
3
1
1
ϩ
ϩ
naphthyl-C), 149.7 (d, JC,P ϭ 1.9 Hz, binaphthyl-C) ppm. P{ H} 386 (62) [M Ϫ CO
NMR (121.50 MHz, CDCl
2
CH
3
], 315 (100) [M Ϫ HNC(iPr)CO
CH Ϫ PO]. HMS (EI) M
NP calcd. 445.1443; found 445.1439.
2
CH
3
ϩ
ϩ
3
, 25 °C): δ ϭ 152.52 (s) ppm. MS FAB 268 (98) [M Ϫ HNC(iPr)CO
2
3
ϩ
ϩ
ϩ
m/z (%) ϭ 486 (55) [M ϩ 1], 485 (30) [M ]. HMS (FAB) [M
] ϭ C32 P calcd. 486.1623; found 486.1629.
ϩ
C
26
H
24
O
4
C
26
H24NO
4
P
1
H25NO
2
(445.45): C 70.11, H 5.43, N 3.14, P 6.95; found C 70.29, H 5.61,
N 3.06, P 6.88.
Synthesis of L11: Ligand L11 was prepared according to the gen-
eral procedure from (aS)-BINOL (1.00 g, 3.50 mmol) and (S)-1-(2-
naphthyl)ethylamine (600 mg, 3.50 mmol). The crude product was
purified by MPLC on a silica gel 60 column [3 cm ϫ 25 cm, flow
Synthesis of L13: Ligand L13 was prepared according to the gen-
eral procedure with (aS)-BINOL (1.00 g, 3.50 mmol) and (S)-valine
methyl ester (458 mg, 3.50 mmol). The crude product was purified
by MPLC, first on a silica gel 60 column [3 cm ϫ 25 cm, flow
70 mL/min; eluent: petroleum ether/ethyl acetate (9:1)] previously
70 mL/min; eluent: petroleum ether/ethyl acetate (95:5)] previously
deactivated with NEt (1 mL). The product obtained was submitted
3
to a second MPLC purification on an aluminum oxide column [ac-
3
deactivated with NEt (1 mL). The resultant product was submitted
tivity IV; 3 cm ϫ 28 cm, flow 50 mL/min; eluent: petroleum ether/
to a second MPLC purification on an aluminum oxide column [ac-
ethyl acetate (95:5)] previously deactivated with NEt
3
(1 mL). tivity IV; 3 cm ϫ 28 cm, flow 50 mL/min; eluent: petroleum ether/
ϭ ϩ221.66 (c ϭ 0.15, ethyl acetate (9:1)] previously deactivated with NEt (1 mL). Yield:
, 25 °C): δ ϭ 1.62 (d, ϭ ϩ428 (c ϭ 0.15,
]THF, 25 °C): δ ϭ 0.82 (d,
19
Yield: 60% (1.00 g), colorless crystals. [α]
D
3
1
22
CHCl
3
). H NMR (300.13 MHz, CDCl
3
67% (1.05 g), colorless crystalline solid. [α]
D
3
3
2
1
J
H,H ϭ 6.8 Hz, 3 H, CH
H, NH), 4.60Ϫ4.90 (m, 1 H, CHCH
H), 7.33Ϫ7.52 (m, 7 H, arom. H), 7.55 (d,
arom. H), 7.71Ϫ8.02 (m, 8 H, arom. H) ppm. C{ H} NMR
3
), 3.56 (dd, JH,H ϭ 6.6, JH,P ϭ 9.6 Hz, CHCl
3
). H NMR (500.13 MHz, [D
H,H ϭ 7.0 Hz, 3 H, Me CH), 0.94 (d,
CH), 1.88Ϫ1.98 (m, 1 H, Me CH), 3.63 (ddd,
H,H ϭ 13.0 Hz, 1 H, CHCO Me), 3.65 (s, 3 H,
H,P ϭ 18.4 Hz 1 H, NH),
8
3
3
1
3
), 7.15Ϫ7.33 (m, 3 H, arom.
J
2
JH,H ϭ 6.7 Hz, 3 H,
3
3
J
H,H ϭ 8.8 Hz, 1 H, Me
2
2
JH,H ϭ 4.7,
13
1
3
3
JH,P ϭ 8.7,
J
2
3
3
2
(
5
125.77 MHz, CDCl
3
, 25 °C): δ ϭ 26.6 (d, JC,P ϭ 4.1 Hz, CH
3
),
CO
2
Me), 4.85 (dd,
J
H,H ϭ 11.4,
J
2
3
0.5 (d, JC,P ϭ 21.4 Hz, CHCH ), 121.8 (d, JC,P ϭ 2.0 Hz, binaph- 7.18Ϫ7.40 (m, 7 H, arom. H), 7.49 (d, JH,H ϭ 9.0 Hz, 1 H, arom.
3
3
thyl-CH) 122.4 (s, binaphthyl-CH), 123.4 (d, JC,P ϭ 2.7 Hz, binaph-
thyl-C), 124.0 (d, JC,P ϭ 4.8 Hz, binaphthyl-C), 124.1, 124.5, 124.7,
H), 7.90Ϫ7.95 (m, 3 H, arom. H), 7.99 (d,
J
H,H ϭ 8.7 Hz, 1 H,
arom. H) ppm. C{ H} NMR (125.77 MHz, [D ]THF, 25 °C): δ ϭ
17.5 (s, Me CH), 19.6 (s, Me CH), 33.2 (d,
Me CH), 51.6 (s, CO Me), 59.4 (d, JC,P ϭ 13.2 Hz, CHCO
1
3
1
8
3
1
1
1
24.8, 125.7, 126.0, 126.1, 126.1, 126.8, 126.9, 127.6, 127.9, 128.2,
28.2, 128.3, 129.4, 130.2 (all s, aromatic-CH), 130.8, 131.4, 132.5,
32.7, 132.7, 133.3 (all s, aromatic-C) 142.9 (d, JC,P ϭ 4.1 Hz, 122.6, 123.0 (both arom. CH), 123.8 (d, JC,P ϭ 2.4 Hz, arom. C),
2
2
J
C,P ϭ 2.8 Hz,
2
2
2
2
Me),
naphthyl-C), 147.6 (d, JC,P ϭ 4.8 Hz, binaphthyl-C), 149.3 (d,
124.9 (d, JC,P ϭ 4.7 Hz, arom. C), 125.3, 125.5, 126.7, 126.8, 127.5,
127.6, 129.1, 129.2, 130.3, 131.0 (all s, arom. CH), 131.9, 132.5,
31
1
JC,P ϭ 1.4 Hz, binaphthyl-C) ppm. P{ H} NMR (121.50 MHz,
CDCl , 25 °C): δ ϭ 150.66 (s) ppm. MS (EI): m/z (%) ϭ 485 (83) 133.7, 133.7 (all s, arom. C), 149.8 (d, JC,P ϭ 5.6 Hz, arom. C),
3
ϩ
ϩ
ϩ
3
[
M ], 315 (33) [M Ϫ NHCHCH
NHCHCH
85.1545; found 485.1555.
3
(C10
H
7
)], 268 (23) [M
Ϫ
150.6 (s, arom. C), 173.7 (d,
J
C,P ϭ 3.3 Hz, COOMe) ppm.
ϩ
31
1
3
(C10
H
7
) Ϫ PO]. HMS (EI) M ϭ C32
H
24
O
2
NP calcd.
P{ H} NMR (202.47 MHz, [D ]THF, 25 °C): δ ϭ 149.23 (s) ppm.
8
ϩ
ϩ
4
MS (EI): m/z (%) ϭ 445 (61) [M ], 402 (32) [M Ϫ CH(CH
3
)
2
],
],
ϩ
ϩ
2 3 2
386 (60) [M Ϫ CO CH ], 315 (100) [M Ϫ HNC(iPr)CO CH
3
ϩ
ϩ
Synthesis of L12: Ligand L12 was prepared according to the gen-
eral procedure with (aR)-BINOL (1.00 g, 3.50 mmol) and (S)-va-
line methyl ester (458 mg, 3.50 mmol). The crude product was puri-
fied by MPLC on a silica gel 60 column [3 cm ϫ 25 cm, flow
2 3
268 (51) [M Ϫ HNC(iPr)CO CH Ϫ PO]. HMS (EI) M ϭ
C H O NP calcd. 445.1443; found. 445.1449. C H NO P
2
6
24
4
26 24
4
(445.45): C 70.11, H 5.43, N 3.14, P 6.95; found C 70.28, H 5.68,
N 3.10, P 6.94.
7
0 mL/min; eluent: petroleum ether/ethyl acetate (9:1)] previously
deactivated with NEt (1 mL). The product thus isolated was sub-
mitted to a second MPLC purification on a aluminum oxide col-
umn [activity IV; 3 cm ϫ 28 cm, flow 50 mL/min; eluent: petroleum treated with substrate (0.50 mmol) and then ligand (0.02 mmol).
I
3
General Procedure for the Ir -Catalysed Allylic Alkylation: A solu-
2
tion of [IrCl(COD)] (6.7 mg, 0.01 mmol) in THF (2 mL) was
ether/ethyl acetate (9:1)] previously deactivated with NEt
3
(1 mL).
ϭ Ϫ390 (c ϭ
]THF, 25 °C): δ ϭ 0.86
CH), 0.94 (d, 3
JH,H ϭ 6.7 Hz, 3 H, solution of dimethyl 2-sodiomalonate was added. This solution was
The resultant solution was stirred for 5 min. If the reaction was
run with additive, this was added at this point (0.50 mmol) and the
solution stirred for a further 5 min. After that, a freshly prepared
22
Yield: 44% (690 mg), colorless crystalline solid. [α]
D
1
0
.13, CHCl
3
). H NMR (500.13 MHz, [D
8
3
(d,
JH,H ϭ 6.7 Hz, 3 H, Me
2
Me
2
CH), 2.00 (dqq, JH,H ϭ 6.4, 3JH,H ϭ 6.7, JH,H ϭ 6.7 Hz, 1 H,
3
3
prepared by suspending sodium hydride (24.0 mg, 1.00 mmol) in
1102
Eur. J. Org. Chem. 2003, 1097Ϫ1103

I
Asymmetric Ir -Catalysed Allylic Alkylation of Monosubstituted Allylic Acetates
FULL PAPER
[
10] [10a]
THF (2 mL) and the dropwise addition of dimethyl malonate
115 µL, 1.00 mmol). The mixture was stirred under the stated reac-
tion conditions, then water (4 mL) was added, and the mixture was
B. Bartels, G. Helmchen, Chem. Commun. 1999, 741Ϫ742.
K. Fuji, N. Kinoshita, K. Tanaka, T. Kawabata, Chem.
[10b]
(
Commun. 1999, 2289Ϫ2290. Note added in proof (February
I
10, 2003): After submission of our work, Ir -catalysed allylic
extracted with diethyl ether (3 ϫ 5 mL). The combined organic
aminations using ligand L6 were reported: T. Ohmura, J. F.
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12] [12a]
4
layers were washed with satd. NH Cl solution (10 mL), dried
(
Na SO ) and concentrated in vacuo. The crude product was puri-
2
4
[11]
fied by flash column chromatography to give a mixture of substitu-
tion products 3 and 4 as colourless oils. For analytical data see
above.
[
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This work was supported by the Deutsche Forschungsgemeinschaft
and the Fonds der Chemischen Industrie. C. G.-Y. thanks the Alex-
ander von Humboldt Foundation for a Postdoctoral Fellowship
and the European Community for a Marie Curie Fellowship, pro-
gram ‘‘Improving Human Research Potential and the Socio-eco-
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[3a]
B. M. Trost, K. Droga, I. Hachiya, T. Emura, D. L.
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R
3b]
24
28.9 min, t (S) ϭ 31.6 min; (E)-4b: t ϭ 45.1 min, [α]D ϭ 27.2
R
R
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999, 1, 141Ϫ144. W: [ G. C. LloydϪJones, A. Pfaltz, Angew.
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t (R) ϭ 35.7 min, t (S) ϭ 36.7 min; (E)-4c: t ϭ 43.8 min
R
R
R
[
[
4]
5]
[4a]
27
Pd:
G. C. Lloyd-Jones, S. C. Stephen, M. Murray, C. P.
D 2 2
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4
348Ϫ4357.
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R
R
[5a]
˚
20
Mo:
M. P. T. Sjögren, H. Frisell, B. Akermark, P. O. Norrby,
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[
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W:
8
1
Fe:
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˚
Ϫ1
863Ϫ8874.
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[
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R
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3
[
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Rh:
581Ϫ5582. Ru:
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[
6d]
Ϫ1
5
Y. Morisaki, T. Kondo, T.-A. Mitsudo, Y.
length: 25 cm ϩ 5 cm precolumn, flow: 0.5 mL min , eluent:
[
6e]
B. M.
nhexane/ iPrOH (95:5), 3e: t (R) ϭ 23.2 min, t (S) ϭ
R
R
2
4
24.6 min; (E)-4e: tR ϭ 28.9 min. [α]D ϭ Ϫ1.4 (c ϭ 0.76, CHCl3)
for 3e with 70% ee (R).
1
101Ϫ1103; Angew. Chem. Int. Ed. 2002, 41, 1059Ϫ1061.
Y. Matsushima, K. Onitsuka, T. Kondo, T.-a. Mitsudo, S. Tak-
[
[
7]
This apparatus was invented in the senior author’s group in the
1980s, cf. G. Wegner, PhD Dissertation, Universität Würzburg,
Würzburg, Germany, 1987. In the meantime, it has become
widely known in the chemical community by oral communica-
tion.
ahashi, J. Am. Chem. Soc. 2001, 123, 10405Ϫ10406.
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R. Takeuchi, M. Kashio, J. Am. Chem. Soc. 1998, 120,
[
8b]
8
1
647Ϫ8655.
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[
9]
Received November 6, 2002
8025Ϫ8026.
[O02610]
Eur. J. Org. Chem. 2003, 1097Ϫ1103
1103