Rhodium-catalyzed asymmetric ring opening reaction of oxabenzonorbornadienes with amines using ZnI2 as the activator

Article abstract of DOI:10.1039/c5ob02331a

The complex of [Rh(COD)Cl]₂ and (R,R)-BDPP was used as an effective catalyst for the asymmetric ring opening reaction of oxabenzonorbornadienes with various amines by employing ZnI₂ as the activator. Under the optimized reaction cond

Full text of DOI:10.1039/c5ob02331a

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DOI: 10.1039/C5OB02331A
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Rhodium-Catalyzed Asymmetric Ring Opening Reaction of
Oxabenzonorbornadienes with Amines Using ZnI2 as Activator
Xin Xu,† Jingchao Chen,† Zhenxiu He, Yongyun Zhou and Baomin Fan*
Received 00th January 20xx,
Accepted 00th January 20xx
The complex of [Rh(COD)Cl]2 and (R,R)-BDPP was used as an effective catalyst for the asymmetric ring opening reaction of
oxabenzonorbornadienes with various amines by employing ZnI2 as activator. Under the optimized reaction conditions,
high enantioselectivities with good yields could be obtained from a wide scope of oxabenzonorbornadienes and amines.
DOI: 10.1039/x0xx00000x
www.rsc.org/
the ARO reaction of azabenzonorbornadienes with amines.16 In
order to further investigate the effect of Lewis acids, we have
studied the rhodium catalyzed ARO reaction of
oxabenzonorbornadienes by using ZnI2 as activator. Herein, we
describe the [Rh(COD)Cl]2/ZnI2 co-catalyzed asymmetric ring
opening reactions of oxabenzonorbornadienes with amines.
Introduction
The desymmetric additional ring opening reaction of
oxa/azabenzonorbornadienes with heteroatom nucleophiles is
an
effective
method
for
the
construction
of
hydronaphthalenes bearing multiple functional groups.1
Caused by the broad existence of chiral hydronaphthalene
structures in natural products and bioactive molecules,2 the
asymmetric version of this type of reactions has attracted
continuous interest and investigation.3 The development of
simple and efficient chiral catalysts for such reactions is
undoubtedly an important and continuing topic for related
researchers. Using Josiphos type ligands, some chiral rhodium
catalysts had been developed by Lautens group and achieved
great success. These rhodium catalysts could promote
phenols,4 alcohols,5 amines,6 thiols,7 carboxylic acids,8 water9
or some other heteroatom compounds,10 to react with
oxa/azabenzonorbornadienes and generate the corresponding
ring opening products. Some iridium catalysts comprising
diphosphine or monophosphine ligands had also been applied
in the ring opening reactions of oxa/azabenzonorbornadienes
with some heteroatom nucleophiles by Yang group,11 Tang
group12 and our own group.13 Recently, inspired by the
successful application of Lewis acids as additives in the
transition metal-catalyzed asymmetric ring opening (ARO)
reactions of oxa/azabenzonorbornadienes with carbo-
nucleophiles,14 we had proved that the combination of chiral
palladium complexes with Lewis acids was very effective on
the ARO reactions of oxa/azabenzonorbornadienes with
heteroatom nucleophiles.15 This methodology was also found
useful in increasing the chiral iridium complexes’ efficiency in
Results and discussion
Our initial trials were carried out with the reaction of aniline
and oxabenzonorbornadiene 1a using a cooperative catalytic
system comprising [Rh(COD)Cl]2 and CuI. As it was shown in
table 1, the bis(oxazoline) ligand (R,R)-Ph-pybox,
monophosphine ligands such as (S)-NMDPP and (R)-Monophos
were proved not suitable for the present reaction (Table 1,
entries 1-3). By employing diphosphine ligand, (R)-BINAP gave
a promising result and the desired chiral hydronaphthalene
product was obtained in low yield and ee (Table 1, entry 4).
Encouraged by this result, further evaluation of other
diphosphine ligands suggested that good yields were obtained
by using (R)-SEGPHOS and (R)-Difluorphos (Table 1, entries 5-
6). By switching to bidentate phosphines bearing point chirality
ultimately led to the discovery that (R,R)-BDPP gave excellent
yield and good enantioselectivity (Table 1, entry 8). Notably,
we observed a decreasing of enantioselectivity in the absence
of CuI, this result indicated that Lewis acid played a unique role
in the present reaction (Table 1, entry 9).
Different additives were then screened and the
experimental results were summarized in table 2. The results
proved that the selection of additives was crucial for higher
yield and enantioselectivity. For example, the addition of
trifluoromethanesulfonic salts, such as CuOTf, AgOTf, Zn(OTf)2,
Fe(OTf)2, and Al(OTf)3 gave no product even though some of
them have been successfully employed in the ring opening
reactions of oxabenzonorbornadienes (Table 2, entries 3, 4, 8,
11, and 13). Some halides, including CuI, CuBr, ZnCl2, ZnBr2,
ZnI2, FeCl2, FeI2, and AlBr3 were further screened. It was found
that ZnCl2 and FeCl2 improved the reaction enantioselectivities
YMU-HKBU Joint Laboratory of Traditional Natural Medicine, Yunnan Minzu
University, Kunming, Yunnan, China. E-mail: adams.bmf@hotmail.com; Fax: 86-
871-65946330
† These authors contributed equally.
‡ Electronic Supplementary Information (ESI) available. See
DOI: 10.1039/x0xx00000x
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82
slightly by slowing down the reaction rate (Table 2, entries 5
and 9 compared with entry 9 in table 1).
7
8
9
10
11
12
13
14
15
16
ZnI2
Zn(OTf)2
FeCl2
FeI2
Fe(OTf)2
AlBr3
Al(OTf)3
nBu4NCl
nBu4NBr
nBu4NI
0.1
14
5
1.5
39
15
39
0.2
0.2
0.1
94
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DOI: 10.1039/C5OB02331A
NR
86
84
NR
66
NR
93
92
93
/
69
73
/
73
/
60
64
74
Table 1. Screening of chiral ligandsa
aThe reaction was carried out with 1a (0.30 mmol), 5.0 equiv of
aniline 2a (1.5 mmol) and 0.1 equiv of additive in 1,4-dioxane
o
(2.0 mL) at 80 C in the presence of [Rh(COD)Cl]2 (2.5 mol %)
and (R,R)-BDPP (6.5 mol %). bIsolated yield after neutral
c
alumina column chromatography. Determined by HPLC with a
Chiralcel AD-H column.
entry
ligand
time (h) yieldb (%) eec (%)
In an attempt to improve the reaction enantioselectivity,
different reaction parameters including solvents and the
reaction temperature were also investigated (Table 3). It was
proved that solvent selection had little impact on the reaction
yield but appeared significant on enantioselectivity, and the
using of MeCN and DCE gave high ees (Table 3, entries 2 and 5).
Temperature experiments showed that the temperatures from
0 C to 80 C had little effect to the reaction outcomes and all
gave satisfactory results (Table 3, entries 5-7). However, when
the ZnI2 loading was decreased to 5 mol%, the yield of
hydronaphthalene decreased sharply to 63% (Table 3, entry 8).
Notably, reducing the loadings of [Rh(COD)Cl]2 to 1.25 mol %
and (R,R)-BDPP to 3.25 mol % also afforded the product in high
yield with good enantioselectivity as well (Table 3, entry 9).
Although the reaction time was prolonged to 4h, in
consideration of reaction economy, it was identified as the
optimum reaction condition.
1
2
3
4
5
6
7
(R,R)-Ph-pybox
(S)-NMDPP
(R)-Monophos
(R)-BINAP
(R)-SEGPHOS
(R)-Difluorphos
(R,R)-DIOP
13
13
14
14
14
13
14
0.2
0.5
trace
trace
Trace
20
83
86
92
95
95
/
/
5
26
10
5
54
71
57
o
o
8
(R,R)-BDPP
(R,R)-BDPP
9d
aThe reaction was carried out with 1a (0.30 mmol), 5.0 equiv of
aniline 2a (1.5 mmol) and 0.1 equiv of CuI in 1,4-dioxane (2.0
o
mL) at 80 C in the presence of [Rh(COD)Cl]2 (2.5 mol %) and
bidentate ligand (6.5 mol %) or monodentate ligand (11.0
mol %). bIsolated yield after neutral alumina column
c
chromatography. Determined by HPLC with a Chiralcel AD-H
column. dNo CuI was added.
And the bromide salts including CuBr, ZnBr2 and AlBr3 further
improved the reaction enantioselectivities (Table 2, entries 2, 6
and 12). Among these halides, iodine salts promoted both the
reaction rate and enantioselectivities (Table 2, entries 1, 7 and
10). Beside Lewis acids, organic halide additives such as
Table 3. Optimization of reaction conditionsa
n
n
nBu4NCl, Bu4NBr and Bu4NI were also tested and the results
indicated that they also accelerated the reaction but only give
moderate enantioselectivities (Table 2, entries 14-16).
Therefore, ZnI2 was found to be optimal in terms of yield and
enantioselectivity.
entry solvent time(h) yieldb (%) eec (%)
1
2
3
4
5
THF
CH3CN
toluene
DMF
DCE
DCE
DCE
DCE
DCE
15
3
3
85
92
92
93
95
90
94
63
94
75
93
79
79
94
94
94
90
94
3
0.1
24
3
7
4
Table 2. Screening of additivesa
6d
7e
8f
9e,g
aThe reaction was carried out with 1a (0.30 mmol), 5.0 equiv of
aniline 2a (1.5 mmol) and 0.1 equiv of ZnI2 in solvent (2.0 mL)
entry additive time (h) yieldb (%) eec (%)
1
2
3
4
5
6
CuI
CuBr
CuOTf
AgOTf
ZnCl2
ZnBr2
0.2
1
14
14
15
1
95
71
trace
NR
30
85
71
73
/
/
60
78
o
at 80 C in the presence of [Rh(COD)Cl]2 (2.5 mol %) and (R,R)-
BDPP (6.5 mol %). Isolated yield after neutral alumina column
chromatography. Determined by HPLC with a Chiralcel AD-H
column. React at 0 C. React at room temperature. 5% ZnI2
b
c
d
o
e
f
2 | J. Name., 2012, 00, 1-3
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was used. g1.25 mol % [Rh(COD)Cl]2 and 3.25 mol % (R,R)-BDPP
were used.
11d
12d
13
3
4
93View Article 9O9nline
DOI: 10.1039/C5OB02331A
With the optimum reaction conditions in hand, various
amines were employed in the present asymmetric ring
opening reaction to extend its scope (Table 4). In general,
amines including aryl amines and alkyl amines were suitable
for this progress and excellent enantioselectivities were
obtained by using primary amines whereas secondary amines
gave good enantioselectivities with faster reaction rate. The
amines bearing halogen substituents on the para-, meta-, and
ortho-position, were suitable to afford the corresponding
products (Table 4, entries 1-4). Other substituted anilines
including N-alkyl anilines also reacted smoothly to generate
the products (Table 4, entries 5-9). To our delight, alkyl amines
87
87
88
87
98
94
20
4
14d
aThe reaction was carried out with 1a (0.30 mmol), 5.0 equiv of
amine 2b-o (1.5 mmol) and 0.1 equiv of ZnI2 in DCE (2.0 mL) at
room temperature in the presence of [Rh(COD)Cl]2 (1.25 mol %)
and (R,R)-BDPP (3.25 mol %). bIsolated yield after neutral
c
alumina column chromatography. Determined by HPLC with a
Chiralcel AD-H, OD-H or OJ-H column. dDCM (dichloromethane)
was used as solvent.
such
as
N-methylbenzylamine,
N-phenylpiperazine,
dibenzylamine, tert-butylamine and piperidine were also
suitable for this protocol (Table 4, entries 10-14). The absolute
configuration of the product 3al was assigned as 1R, 2R by an
X-ray crystallographic analysis (Figure 1, for details, see the
Supporting Information).17 As same as the ring opening
product reported by Lautens,6c by using indole as nucleophile,
3ap was obtained (Scheme 1).
Scheme 1. The reaction of oxabenzonorbornadiene and indole
Table 4. Scope of aminesa
entry
1
amine
time yieldb (%) eec (%)
Figure 1. X-ray structure of 3al
.
14
23
93
56
99
98
Using 4-chloroaniline 2e as nucleophile,
a
range of
oxabenzonorbornadienes were also examined in this
asymmetric ring opening reaction. As it was shown in table 5,
all of the tested oxabenzonorbornadienes could react with 4-
chloroaniline efficiently to give the corresponding
hydronaphthalenes with excellent enantioselectivities (95%-99%
ee), whereas the oxabenzonorbornadiene with relatively bulky
groups afforded a moderate yield (Table 5, entry 2).
2
3
4
23
14
14
14
1
81
94
83
83
86
99
99
95
96
90
5
Table 5. Scope of oxabenzonorbornadiene derivativesa
6
7d
yieldb
(%)
eec
(%)
entry oxabenzonorbornadiene time
8d
1
95
88
1
2
3
4
95
64
93
98
95
99
9d
1
5
75
89
89
81
11
11
10d
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In summary, by using ZnI2 as activator, the rhodium complex of
[Rh(COD)Cl]2 and (R,R)-BDPP was found an efficient catalyst for
View Article Online
DOI: 10.1039/C5OB02331A
4
5
6
5
3
75
89
81
99
98
95
the
asymmetric
ring
opening
reactions
of
oxabenzonorbornadienes with amines. Promoted by this
rhodium/ZnI2 co-catalytic system, various amines, including
aryl amines and alkyl amines could serve as suitable
nucleophiles to react smoothly with oxabenzonorbornadienes
1a. The corresponding ring opening products could be
generated in good yields with generally excellent
enantioselectivities. Also, oxabenzonorbornadienes with
different substituents were also tested in this co-catalytic
system. Further mechanistic studies toward the particular
effect of Lewis acid and synthetic application are ongoing in
our laboratory.
10
aThe reaction was carried out with 1b-g (0.30 mmol), 5.0 equiv
of 4-chloroaniline 2e (1.5 mmol) and 0.1 equiv of ZnI2 in DCE
(2.0 mL) at room temperature in the presence of [Rh(COD)Cl]2
(1.25 mol %) and (R,R)-BDPP (3.25 mol %). bIsolated yield after
neutral alumina column chromatography. cDetermined by
HPLC with a Chiralcel AD-H column or AS-H column.
A general mechanism for this type of reactions has been
proposed by the groups of Lautens6d, 18, Tang12 and Yang11b
.
Experimental section
General
However, in consideration of the effect of Lewis acid on the
reaction and the variation of the enantioselectivities with
different amines as nucleophiles, another reaction pathway
was hypothesized here for this chiral rhodium complex/ZnI2
co-catalyzed asymmetric ring opening reaction of
oxabenzonorbornadienes with amines (Figure 2). The catalytic
cycle is initiated by the coordination of [Rh(cod)Cl]2 with (R,R)-
The reactions and manipulations were performed under an
atmosphere of argon by using standard Schlenk techniques
and Drybox (Mikrouna, Supper 1220/750). Anhydrous toluene
and THF (tetrahydrofuran) were distilled from sodium
benzophenone ketyl prior to use. Anhydrous DCE
(dichloroethane), DMF (N,N-dimethylformamide) and CH3CN
(acetonitrile) were distilled from calcium hydride and stored
BDPP to generate the chiral rhodium complex
coordination of with 1a, zinc ion, and aniline leads to the
intermediate . Subsequently, the intermediate undergoes
addition reaction and affords intermediate , which then gives
the ring-opened species by β-elimination and rearragement.
Next, intermediate can be transformed into via reductive
A. The following
A
1
under argon. H NMR and 13C NMR spectra were recorded on
B
B
Bruker-Avance 400 MHz spectrometer. CDCl3 was used as
solvent. Chemical shifts (δ) were reported in ppm with
tetramethylsilane as internal standard, and J values were given
in Hz. The enantioselective excesses were determined by
C
D
D
E
elimination. Finally, product 3aa was formed by cation
Agilent 1260 Series HPLC using Daicel AD-H、AS-H、OD-H、
dissociation.
OJ-H chiral columns eluted with a mixture of isopropyl alcohol
and hexane. Melting points were measured on X-4 melting
point apparatus and uncorrected. High resolution mass spectra
(HRMS) were performed on a VG Autospec-3000 spectrometer.
Column chromatography was performed with neutral alumina
with petroleum ether and ethyl acetate as eluents.
Typical procedure for rhodium/ZnI2-cocatalyzed asymmetric
ring opening reaction of oxabenzonorbornadienes with
amines.
[Rh(COD)Cl]2 (1.8 mg, 0.0037 mmol), (R,R)-BDPP (4.3 mg,
0.0097 mmol) and 1.0 mL DCE were added to a Schlenk tube
under an argon atmosphere. The resulting solution was stirred
at room temperature for 30 min, then ZnI2 (9.6 mg, 0.03 mmol)
was added and stirred for additional 10 min, then
oxabenzonorbornadiene 1a (43.2 mg, 0.3 mmol) was added,
and the mixture was stirred for an additional 10 min. After the
addition of aniline 2a (139.5 mg, 1.5 mmol) and DCE (1.0 mL),
the mixture was stirred at room temperature under argon
atmosphere with TLC monitoring until the complete
consumption of 1a. The reaction mixture was concentrated.
The residue was purified by chromatography on a neutral
alumina column to afford the desired product 3aa (66.9 mg, 94%
yield). The enantioselective excess value of the product was
determined by HPLC on a chiral stationary phase (94% ee).
Figure 2. Proposed mechanism for [Rh(COD)Cl]2/ZnI2-
cocatalyzed ARO reaction of oxabenzonorbornadiene 1a and
amine 2a
.
Conclusions
4 | J. Name., 2012, 00, 1-3
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(1R,2R)-2-(phenylamino)-1,2-dihydronaphthalen-1-ol (3aa)
ARTICLE
4.23 (ddd, J = 8.1, 3.3, 1.8 Hz, 1H), 2.24 (s, 3H). The ee of 3af
View Article Online
White solid, 94% yield, 94% ee. 1H NMR (400 MHz, CDCl3) δ was determined by HPLC analysis usingDDOaI:ic1e0l.10C3h9i/rCa5lcOeBl0A23D3-1HA
7.48 (d, J = 6.3 Hz, 1H), 7.32 – 7.13 (m, 5H), 6.75 (dd, J = 22.9, column (25 cm × 0.46 cm ID), conditions: n-hexane/i-PrOH =
7.5 Hz, 3H), 6.56 (d, J = 9.6 Hz, 1H), 6.02 (d, J = 9.4 Hz, 1H), 4.84 80/20, 1.0 mL/min, 254 nm; tminor = 8.70 min, tmajor = 10.93 min.
(d, J = 7.5 Hz, 1H), 4.33 (d, J = 5.4 Hz, 1H). The ee of 3aa was
determined by HPLC analysis using Daicel Chiralcel AD-H (1R,2R)-2-((4-methoxyphenyl)amino)-1,2-dihydronaphthalen-
column (25 cm × 0.46 cm ID), conditions: n-hexane/i-PrOH = 1-ol (3ag)
1
80/20, 1.0 mL/min, 254 nm; tminor = 8.28 min, tmajor = 10.20 min. White solid, 83% yield, 96% ee. H NMR (400 MHz, CDCl3) δ
7.51 – 7.49 (m, 1H), 7.30 – 7.27 (m, 2H), 7.15 – 7.12 (m, 1H),
(1R,2R)-2-((4-bromophenyl)amino)-1,2-dihydronaphthalen-1- 6.82 – 6.78 (m, 2H), 6.70 – 6.69 (m, 2H), 6.53 (dd, J = 9.7, 1.4
ol (3ab)
Hz, 1H), 6.00 (dd, J = 9.6, 3.3 Hz, 1H), 4.82 (d, J = 8.4 Hz, 1H),
1
White solid, 93% yield, 99% ee. H NMR (400 MHz, CDCl3) δ 4.21 (ddd, J = 8.4, 3.1, 1.9 Hz, 1H), 3.76 (s, 3H), 3.00 (s, 1H).
7.33 (d, J = 7.1 Hz, 1H), 7.23 – 7.11 (m, 4H), 7.10 – 7.01 (m, 1H), The ee of 3ag was determined by HPLC analysis using Daicel
6.49 – 6.41 (m, 3H), 5.86 (dd, J = 9.6, 3.7 Hz, 1H), 4.68 (d, J = Chiralcel AD-H column (25 cm × 0.46 cm ID), conditions: n-
7.4 Hz, 1H), 4.16 – 4.09 (m, 1H), 3.55 (s, 1H). The ee of 3ab was hexane/i-PrOH = 80/20, 1.0 mL/min, 254 nm; tminor = 12.32 min,
determined by HPLC analysis using Daicel Chiralcel AD-H tmajor = 15.73 min.
column (25 cm × 0.46 cm ID), conditions: n-hexane/i-PrOH =
80/20, 1.0 mL/min, 254 nm; tminor = 10.34 min, tmajor = 11.32 (1R,2R)-2-(methyl(phenyl)amino)-1,2-dihydronaphthalen-1-ol
min.
(3ah)
Colorness oil, 86% yield, 90% ee. H NMR (400 MHz, CDCl3) δ
(1R,2R)-2-((2-bromophenyl)amino)-1,2-dihydronaphthalen-1- 7.45 (d, J = 4.3 Hz, 1H), 7.26 – 7.18 (m, 4H), 7.06 (d, J = 4.2 Hz,
ol (3ac) 1H), 6.74 (d, J = 8.4 Hz, 2H), 6.53 (d, J = 9.8 Hz, 1H), 5.81 (d, J =
1
1
White solid, 56% yield, 98% ee. H NMR (400 MHz, CDCl3) δ 9.8 Hz, 1H), 4.99 (d, J = 9.4 Hz, 1H), 4.60 (d, J = 9.4 Hz, 1H), 2.73
7.52 – 7.45 (m, 2H), 7.33 – 7.15 (m, 4H) , 6.88 (d, J = 8.2 Hz, 1H), (s, 3H), 2.14 (s, 1H). The ee of 3ah was determined by HPLC
6.69 – 6.55 (m, 2H), 5.99 (d, J = 9.6 Hz, 1H), 4.91 (d, J = 7.1 Hz, analysis using Daicel Chiralcel OD-H column (25 cm × 0.46 cm
1H), 4.36 (s, 2H), 2.42 (s, 1H). The ee of 3ac was determined by ID), conditions: n-hexane/i-PrOH = 90/10, 1.0 mL/min, 254 nm;
HPLC analysis using Daicel Chiralcel AD-H column (25 cm × 0.46 tminor = 14.01 min, tmajor = 10.86 min.
cm ID), conditions: n-hexane/i-PrOH = 90/10, 1.0 mL/min, 254
nm; tminor= 10.57 min, tmajor = 11.61 min.
(1R,2R)-2-((4-methoxyphenyl)(methyl)amino)-1,2-
dihydronaphthalen-1-ol (3ai)
1
(1R,2R)-2-((3-bromophenyl)amino)-1,2-dihydronaphthalen-1- Colorness oil, 98% yield, 88% ee. H NMR (400 MHz, CDCl3) δ
ol (3ad)
7.45 (d, J = 5.4 Hz, 1H), 7.15 – 7.12 (m, 2H), 6.98 (d, J = 5.7 Hz,
White solid, 81% yield, 99% ee. 1H NMR (400 MHz, CDCl3) δ 1H), 6.82 (d, J = 8.4 Hz, 2H), 6.72 (d, J = 8.3 Hz, 2H), 6.44 (d, J =
7.36 (d, J = 6.9 Hz, 1H), 7.24 – 7.17 (m, 2H), 7.06 (d, J = 6.9 Hz, 9.7 Hz, 1H), 5.83 (d, J = 9.6 Hz, 1H), 4.96 (d, J = 10.3 Hz, 1H),
1H), 6.94 (t, J = 7.9 Hz, 1H), 6.78 – 6.75 (m, 2H), 6.50 (t, J = 8.9 4.41 (d, J = 10.0 Hz, 1H), 3.64 (s, 2H), 2.65 (s, 3H). The ee of 3ai
Hz, 2H), 5.89 (dd, J = 9.6, 3.4 Hz, 1H), 4.72 (d, J = 7.2 Hz, 1H), was determined by HPLC analysis using Daicel Chiralcel OD-H
4.18 (s, 1H). The ee of 3ad was determined by HPLC analysis column (25 cm × 0.46 cm ID), conditions: n-hexane/i-PrOH =
using Daicel Chiralcel AD-H column (25 cm × 0.46 cm ID), 90/10, 1.0 mL/min, 254 nm; tminor = 12.85 min, tmajor = 15.27
conditions: n-hexane/i-PrOH = 80/20, 1.0 mL/min, 254 nm; min.
tminor = 7.20 min, tmajor = 9.58 min.
(1R,2R)-2-(ethyl(phenyl)amino)-1,2-dihydronaphthalen-1-ol
(1R,2R)-2-((4-chlorophenyl)amino)-1,2-dihydronaphthalen-1-
(3aj)
Colorness oil, 75% yield, 89% ee. H NMR (400 MHz, CDCl3) δ
1
ol (3ae)
1
White solid, 94% yield, > 99% ee. H NMR (400 MHz, CDCl3) δ 7.45 – 7.43 (m, 1H), 7.20 – 7.12 (m, 3H), 7.05 (d, J = 3.8 Hz, 1H),
7.43 (d, J = 6.8 Hz, 1H), 7.31 – 7.24 (m, 2H), 7.14 – 7.10 (m, 3H), 6.87 (d, J = 8.1 Hz, 2H), 6.69 (t, J = 7.3 Hz, 1H), 6.51 (d, J = 9.7
6.57 (dd, J = 15.0, 9.3 Hz, 3H), 5.96 (dd, J = 9.6, 3.7 Hz, 1H), Hz, 1H), 5.89 – 5.86 (m, 1H), 5.02 (d, J = 9.3 Hz, 1H), 4.59 (d, J =
4.78 (d, J = 7.5 Hz, 1H), 4.26 – 4.19 (m, 1H). The ee of 3ae was 9.2 Hz, 1H), 3.27 (q, J = 7.0 Hz, 2H), 2.29 (s, 1H), 1.07 (t, J = 7.0
determined by HPLC analysis using Daicel Chiralcel AD-H Hz, 3H). The ee of 3aj was determined by HPLC analysis using
column (25 cm × 0.46 cm ID), conditions: n-hexane/i-PrOH = Daicel Chiralcel OD-H column (25 cm × 0.46 cm ID), conditions:
80/20, 0.8 mL/min, 254 nm; tminor = 12.22 min, tmajor = 13.25 n-hexane/i-PrOH = 90/10, 1.0 mL/min, 254 nm; tminor = 9.53
min.
min, tmajor = 7.99 min.
(1R,2R)-2-(p-tolylamino)-1,2-dihydronaphthalen-1-ol (3af)
White solid, 83% yield, 95% ee. H NMR (400 MHz, CDCl3) δ (3ak)
7.45 – 7.43 (m, 1H), 7.29 – 7.21 (m, 2H), 7.11 – 7.09 (m, 1H), Colorness oil, 89% yield, 81% ee. H NMR (400 MHz, CDCl3) δ
6.99 (d, J = 8.2 Hz, 2H), 6.59 (d, J = 8.4 Hz, 2H), 6.50 (dd, J = 9.7, 7.49 (d, J = 7.2 Hz, 1H), 7.22 (d, J = 4.2 Hz, 4H), 7.17 – 7.09 (m,
1.4 Hz, 1H), 5.97 (dd, J = 9.6, 3.5 Hz, 1H), 4.79 (d, J = 8.1 Hz, 1H), 4H), 6.96 (d, J = 7.2 Hz, 1H), 6.45 (d, J = 9.9 Hz, 1H), 6.02 (d, J =
(1R,2R)-2-(benzyl(methyl)amino)-1,2-dihydronaphthalen-1-ol
1
1
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Organic & Biomolecular Chemistry
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ARTICLE
Journal Name
9.9 Hz, 1H), 4.85 (d, J = 12.0 Hz, 1H), 3.75 (d, J = 13.3 Hz, 1H), (dd, J = 9.5, 3.6 Hz, 1H), 4.92 (d, J = 8.0 Hz, 1H), 3.V9i9ew–Ar3tic.9le7On(lmine,
DOI: 10.1039/C5OB02331A
3.50 (d, J = 13.1 Hz, 2H), 2.24 (s, 3H). The ee of 3ak was 1H). The ee of 3ap was determined by HPLC analysis using
determined by HPLC analysis using Daicel Chiralcel OJ-H Daicel Chiralcel AD-H column (25 cm × 0.46 cm ID), conditions:
column (25 cm × 0.46 cm ID), conditions: n-hexane/i-PrOH = n-hexane/i-PrOH = 80/20, 1.0 mL/min, 254 nm, tminor = 14.60
95/5, 1.0 mL/min, 254 nm; tminor = 18.51 min, tmajor = 15.97 min. min, tmajor = 17.75 min.
(1R,2R)-2-(4-phenylpiperazin-1-yl)-1,2-dihydronaphthalen-1-
(1R,2R)-2-((4-chlorophenyl)amino)-6,7-dimethyl-1,2-
ol (3al)
dihydronaphthalen-1-ol (3be)
White solid, 93% yield, >99.9% ee. 1H NMR (400 MHz, CDCl3) δ White solid, 95% yield, 98% ee. mp 146 – 148 C. 1H NMR (400
7.58 (d, J = 7.1 Hz, 1H), 7.28 – 7.21 (m, 4H), 7.07 (d, J = 7.1 Hz, MHz, CDCl3) δ 7.20 (s, 1H), 7.14 – 7.12 (m, 2H), 6.95 (s, 1H),
1H), 6.93 – 6.85 (m, 3H), 6.54 (d, J = 9.9 Hz, 1H), 6.11 (d, J = 9.9 6.63 – 6.59 (m, 2H), 6.54 (d, J = 9.7 Hz, 1H), 5.94 (dd, J = 9.6,
Hz, 1H), 4.91 (d, J = 11.5 Hz, 1H), 3.50 (d, J = 11.5 Hz, 1H), 3.21 4.1 Hz, 1H), 4.75 (d, J = 6.3 Hz, 1H), 4.24 – 4.21 (m, 1H), 2.26 (s,
(m, 4H), 2.95 (d, J = 7.6 Hz, 2H), 2.69 (d, J = 5.9 Hz, 2H). The ee 6H), 13C NMR (100 MHz, CDCl3) δ 145.52, 137.35, 137.23,
of 3al was determined by HPLC analysis using Daicel Chiralcel 132.79, 129.55, 129.30, 129.03, 128.65, 126.22, 122.97, 115.16,
AD-H column (25 cm × 0.46 cm ID), conditions: n-hexane/i- 71.02, 55.43, 20.01, 19.84. MS (ESI) calcd for C18H18ClNO (M+):
PrOH = 95/5 with 0.1% tert-Butylamine, 1.0 mL/min, 254 nm, 299.1064; Found: 299.1077. The ee of 3be was determined by
o
tminor = 15.60 min, tmajor = 17.37 min.
HPLC analysis using Daicel Chiralcel AD-H column (25 cm × 0.46
cm ID), conditions: n-hexane/i-PrOH = 90/10, 1.0 mL/min, 254
nm, tminor = 17.70 min, tmajor = 21.78 min.
(1R,2R)-2-(dibenzylamino)-1,2-dihydronaphthalen-1-ol (3am)
1
Colorness oil, 87% yield, 87% ee. H NMR (400 MHz, CDCl3) δ
7.43 (d, J = 6.9 Hz, 1H), 7.24 (d, J = 4.1 Hz, 8H), 7.16 – 7.10 (m, (1R,2R)-2-((4-chlorophenyl)amino)-5,8-dimethoxy-1,2-
4H), 6.96 (d, J = 6.9 Hz, 1H), 6.47 (d, J = 9.9 Hz, 1H), 6.06 (d, J = dihydronaphthalen-1-ol (3ce)
o
1
9.9 Hz, 1H), 4.94 (d, J = 11.7 Hz, 1H), 3.89 (d, J = 13.6 Hz, 2H), White solid, 64% yield, 95% ee. mp 70 – 72 C. H NMR (400
3.59 (d, J = 11.7 Hz, 1H), 3.51 (d, J = 13.6 Hz, 2H), 2.98 (s, 1H). MHz, CDCl3) δ 7.12 (d, J = 8.5 Hz, 2H), 7.04 (d, J = 9.8 Hz, 1H),
The ee of 3am was determined by HPLC analysis using Daicel 6.80 (q, J = 9.0 Hz, 2H), 6.60 (d, J = 8.6 Hz, 2H), 6.09 (dd, J = 9.7,
Chiralcel OD-H column (25 cm × 0.46 cm ID), conditions: n- 5.6 Hz, 1H), 5.15 (s, 1H), 4.26 (d, J = 3.6 Hz, 1H), 3.83 (s, 3H),
hexane/i-PrOH = 90/10, 1.0 mL/min, 254 nm, tminor = 6.92 min, 3.77 (s, 3H), 2.35 (s, 1H), 13C NMR (100 MHz, CDCl3) δ 151.99,
tmajor = 5.82 min.
149.84, 145.09, 129.19, 125.05, 123.38, 122.42, 122.10, 121.28,
114.35, 111.64, 111.07, 63.55, 56.19, 55.91, 52.56. MS (ESI)
(1R,2R)-2-(tert-butylamino)-1,2-dihydronaphthalen-1-ol (3an) calcd for C18H18ClNO3 (M+): 331.0975; Found: 331.0984. The ee
White solid, 87% yield, 98% ee. H NMR (400 MHz, CDCl3) δ of 3ce was determined by HPLC analysis using Daicel Chiralcel
1
7.50 (d, J = 7.4 Hz, 1H), 7.21 – 7.13 (m, 2H), 6.99 – 6.97 (m, 1H), AD-H column (25 cm × 0.46 cm ID), conditions: n-hexane/i-
6.31 (dd, J = 9.7, 2.4 Hz, 1H), 5.88 (dd, J = 9.7, 2.3 Hz, 1H), 4.43 PrOH = 80/20, 1.0 mL/min, 254 nm, tminor = 15.30 min, tmajor
(d, J = 11.6 Hz, 1H), 3.41 (dt, J = 11.6, 2.3 Hz, 1H), 1.10 (s, 9H). 19.20 min.
=
13C NMR (100 MHz, CDCl3) δ 136.80, 132.13, 130.65, 128.21,
128.01, 127.62, 126.12, 124.84, 72.15, 56.47, 53.60, 29.37. MS (1R,2R)-2-((4-chlorophenyl)amino)-6,7-dimethoxy-1,2-
(ESI) calcd for C14H19NO (M+): 217.1467; Found: 217.1470. The dihydronaphthalen-1-ol (3de)
o
ee of 3an was determined by HPLC analysis using Daicel White solid, 93% yield, 99% ee. mp 179 – 180 C. 1H NMR (400
Chiralcel AD-H column (25 cm × 0.46 cm ID), conditions: n- MHz, CDCl3) δ 7.06 (d, J = 8.8 Hz, 2H), 6.93 (s, 1H), 6.61 – 6.54
hexane/i-PrOH = 80/20 with 0.1% tert-Butylamine, 1.0 mL/min, (m, 3H), 6.42 (d, J = 9.6 Hz, 1H), 5.83 (dd, J = 9.6, 3.9 Hz, 1H),
254 nm; tminor = 3.91 min, tmajor = 4.36 min.
4.66 (d, J = 6.9 Hz, 1H), 4.17 – 4.15 (m, 2H), 3.82 (d, J = 1.5 Hz,
6H). 13C NMR (100 MHz, CDCl3) δ 148.90, 148.86, 145.28,
129.28, 128.44, 127.98, 125.22, 124.59, 122.85, 114.99, 110.92,
(1R,2R)-2-(piperidin-1-yl)-1,2-dihydronaphthalen-1-ol (3ao)
1
Colorness oil, 88% yield, 94% ee. H NMR (400 MHz, CDCl3) δ 110.33, 71.14, 56.08, 55.51. MS (ESI) calcd for C18H18ClNO3
7.57 (d, J = 7.2 Hz, 1H), 7.27 – 7.18 (m, 2H), 7.04 (d, J = 7.2 Hz, (M+): 331.0975; Found: 331.0969. The ee of 3de was
1H), 6.49 (d, J = 9.8 Hz, 1H), 6.11 (d, J = 9.9 Hz, 1H), 4.86 (d, J = determined by HPLC analysis using Daicel Chiralcel AD-H
12.1 Hz, 1H), 3.38 (d, J = 12.1 Hz, 1H), 2.76 – 2.74 (m, 2H), 2.47 column (25 cm × 0.46 cm ID), conditions: n-hexane/i-PrOH =
– 2.45 (m, 2H), 1.63 – 1.57 (m, 4H), 1.49 – 1.46 (m, 2H). The ee 80/20, 1.0 mL/min, 254 nm, tminor = 14.98 min, tmajor = 27.46
of 3ao was determined by HPLC analysis using Daicel Chiralcel min.
OJ-H column (25 cm × 0.46 cm ID), conditions: n-hexane/i-
PrOH = 99/1, 1.0 mL/min, 254 nm; tminor = 12.07 min, tmajor
9.83 min.
=
(6R,7R)-7-((4-chlorophenyl)amino)-2,3,6,7-tetrahydronaph-
tho[2,3-b][1,4]dioxin-6-ol (3ee)
o
White solid, 75% yield, 99% ee. mp 185 – 187 C. 1H NMR (400
(1S,2S)-2-(1H-indol-3-yl)-1,2-dihydronaphthalen-1-ol (3ap)
MHz, CDCl3) δ 7.13 (d, J = 8.6 Hz, 2H), 6.96 (s, 1H), 6.68 (s, 1H),
1
White solid, 89% yield, 90% ee. H NMR (400 MHz, CDCl3) δ 6.61 (d, J = 8.6 Hz, 2H), 6.45 (d, J = 9.6 Hz, 1H), 5.89 (dd, J = 9.6,
7.93 (s, 1H), 7.66 (d, J = 7.9 Hz, 1H), 7.30 (d, J = 7.3 Hz, 1H), 3.9 Hz, 1H), 4.68 (d, J = 6.6 Hz, 1H), 4.25 (s, 4H), 4.20 – 4.18 (m,
7.24 – 7.02 (m, 6H), 6.81 (s, 1H), 6.56 (d, J = 9.5 Hz, 1H), 6.07 1H), 13C NMR (100 MHz, CDCl3) δ 145.43, 143.59, 143.48,
6 | J. Name., 2012, 00, 1-3
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Organic & Biomolecular Chemistry
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ARTICLE
3 (a) Y. H. Cho, N. W. Tseng, H. Senboku and M. Lautens, Synthesis,
2008, 15, 2467-2475; (b) C. DockendorffD, OS.I:J1.0J.1in0,3V9Mie/wC.5AOOrtliBcsle0en2O3,n3lMi1nAe.
Lautens, M. Coupal, L. Hodzic, N. Spear, K. Payza, C. Walpole and
M. J. Tomaszewski, Bioorg. Med. Chem. Lett., 2009, 19, 1228-
1232; (c) C. Liébert, M. K. Brinks, A. G. Capacci, M. J. Fleming and
M. Lautens, Org. Lett., 2011, 13, 3000-3003.
4 (a) M. Lautens and Y. Q. Fang, Org. Lett., 2003, 5, 3679-3682; (b)
M. Lautens, K. Fagnou and M. Taylor, Org. Lett., 2000, 2, 1677-
1679.
129.39, 129.01, 128.29, 125.61, 125.54, 122.92, 117.07, 116.02,
115.07, 70.84, 64.59, 64.55, 55.36. MS (ESI) calcd for
C18H16ClNO3 (M+): 329.0819; Found: 329.0806. The ee of 3ee
was determined by HPLC analysis using Daicel Chiralcel AS-H
column (25 cm × 0.46 cm ID), conditions: n-hexane/i-PrOH =
70/30, 1.0 mL/min, 254 nm, tminor = 14.65 min, tmajor = 21.33
min.
5 (a) M. Lautens, K. Fagnou, M. Taylor and T. Rovis, J. Organomet.
Chem., 2001, 624, 259-270; (b) G. C. Tsui, P. Dougan and M.
Lautens, Org. Lett., 2015, DOI: 10.1021/ol4009393.
6 (a) M. Lautens, K. Fagnou and T. Rovis, J. Am. Chem. Soc., 2000,
122, 5650-5651; (b) M. Lautens and K. Fagnou, J. Am. Chem. Soc.,
2001, 123, 7170-7171; (c) M. Lautens, K. Fagnou and D. Q. Yang, J.
Am. Chem. Soc., 2003, 125, 14884-14892; (d) Y. H. Cho, V. Zunic,
H. Senboku, M. Olsen and M. Lautens, J. Am. Chem. Soc., 2006,
128, 6837-6846.
7 P. Leong and M. Lautens, J. Org. Chem., 2004, 69, 2194-2196.
8 M. Lautens and K. Fagnou, Tetrahedron, 2001, 57, 5067-5072.
9 G. C. Tsui and M. Lautens, Angew. Chem. Int. Ed., 2012, 51, 1-6.
10 (a) G. C. Tsui, J. Tsoung, P. Dougan and M. Lautens, Org. Lett.,
2012, 14, 5542-5545; (b) M. Murakami and H. Igawa, Chem.
Commun., 2002, 4, 390-391.
11 (a) D.-Q. Yang, Y.-H. Long, H. Wang and Z.-M. Zhang, Org. Lett.,
2008, 10, 4723-4726; (b) D.-Q. Yang, Y.-H. Long, J.-F. Zhang, H.-P.
Zeng, S.-Y. Wang and C.-R. Li, Organometallics, 2010, 29, 3477-
3480; (c) H.-C. Cheng and D.-Q. Yang, J. Org. Chem., 2012, 77,
9756-9765; (d) Y.-H. Long, W.-L. Wang, D.-Q. Yang, H. Jiang, K.-X.
Chen and Y.-L. Fang, Mol. Divers., 2014, 18, 101-110.
(5R,6R)-6-((4-chlorophenyl)amino)-5,6-dihydronaphtho[2,3-
d][1,3]dioxol-5-ol (3fe)
o
White solid, 89% yield, 98% ee. mp 131 – 133 C. 1H NMR (400
MHz, CDCl3) δ 7.13 (d, J = 8.4 Hz, 2H), 6.95 (s, 1H), 6.66 – 6.58
(m, 3H), 6.44 (d, J = 9.6 Hz, 1H), 5.95 (s, 2H), 5.89 (dd, J = 9.6,
3.6 Hz, 1H), 4.68 (d, J = 7.1 Hz, 1H), 4.20 (s, 1H), 13C NMR (100
MHz, CDCl3) δ 147.59, 147.36, 145.26, 129.64, 129.28, 128.50,
126.00, 125.38, 122.90, 115.02, 108.39, 107.47, 101.23, 71.31,
55.44. MS (ESI) calcd for C17H14ClNO3 (M+): 315.0662; Found:
315.0674. The ee of 3fe was determined by HPLC analysis
using Daicel Chiralcel AS-H column (25 cm × 0.46 cm ID),
conditions: n-hexane/i-PrOH = 80/20, 1.0 mL/min, 254 nm,
tminor = 18.09 min, tmajor = 22.99 min.
(1R,2R)-6,7-dibromo-2-((4-chlorophenyl)amino)-1,2-
dihydronaphthalen-1-ol (3ge)
o
White solid, 81% yield, 95% ee. mp 172 – 176 C. 1H NMR (400
12 R.-S. Luo, J.-H. Liao, L. Xie, W.-J. Tang and A. S. C. Chan, Chem.
Commun., 2013, 49, 9959-9961.
MHz, DMSO-d6) δ 7.71 (s, 1H), 7.60 (s, 1H), 7.09 (d, J = 8.5 Hz,
2H), 6.66 (d, J = 8.5 Hz, 2H), 6.56 (d, J = 9.7 Hz, 1H), 6.03 (dd, J
= 9.6, 2.8 Hz, 1H), 5.84 (d, J = 7.5 Hz, 1H), 5.67 (d, J = 5.5 Hz,
1H), 4.64 (t, J = 6.6 Hz, 1H), 4.10 (s, 1H), 2.50 (s, 1H). 13C NMR
(100 MHz, DMSO-d6) δ 146.63, 138.83, 133.62, 132.05, 131.28,
130.74, 128.56, 125.56, 122.71, 121.94, 119.15, 114.04, 68.99,
54.29. MS (ESI) calcd for C16H12Br2ClNO (M+): 426.8974; Found:
426.8966. The ee of 3ge was determined by HPLC analysis
using Daicel Chiralcel AD-H column (25 cm × 0.46 cm ID),
conditions: n-hexane/i-PrOH = 80/20, 1.0 mL/min, 254 nm,
tminor = 8.51 min, tmajor = 10.25 min.
13 L. Yu, Y.-Y. Zhou, X. Xu, S.-F. Li, J.-B. Xu, B.-M. Fan, C.-Y. Lin, Z.-X.
Bian and A. S. C. Chan, Tetrahedron Lett., 2014, 55, 6315-6318.
14 (a) B.-M. Fan, S.-F. Li, H.-L. Chen, Z.-W. Lu, S.-S. Liu, Q.-J. Yang, L.
Yu, J.-B. Xu, Y.-Y. Zhou and J. Wang, Adv. Synth. Catal., 2013, 355,
2827-2832; (b) S.-S. Liu, S.-F. Li, H.-L. Chen, Q.-J. Yang, J.-B. Xu, Y.-
Y. Zhou, M.-L. Yuan, W.-M. Zeng and B.-M. Fan, Adv. Synth. Catal.,
2014, 356, 2960-2964; (c) J.-C. Chen, S.-S. Liu, Y.-Y. Zhou, S.-F. Li,
C.-Y. Lin, Z.-X. Bian and B.-M. Fan, Organometallics, 2015, 34,
4318-4322.
15 (a) Z.-W. Lu, J. Wang, B.-Q. Han, S.-F. Li, Y.-Y. Zhou and B.-M. Fan,
Adv. Synth. Catal. 2015, 357, 3121-3125; (b) S.-F. Li, J.-B. Xu, B.-M.
Fan, Z.-W. Lu, C.-Y. Zeng, Z.-X. Bian, Y.-Y. Zhou and J. Wang, Chem.
Eur. J., 2015, 21, 9003-9007.
16 C.-Y. Zeng, F. Yang, J.-C. Chen, J. Wang and B.-M. Fan, Org.
Biomol. Chem., 2015, 13, 8425-8428.
Acknowledgements
We thank the National Natural Science Foundation of China
(21362043, 21162040, 21302162, 21572198), the Government
of Yunnan Province (2012FB170) for financial support.
17 X-ray crystallographic data have been deposited in the
Cambridge
Crystallographic
Data
Centre
database
(http://www.ccdc.cam.ac.uk/) under accession code CCDC
1436041.
18 M. Lautens and K. Fagnou, PNAS, 2004, 101, 5455-5460.
Notes and references
1 (a) M. Lautens, K. Fagnou and S. Hiebert, Acc. Chem. Res., 2003,
36, 48-58; (b) D. K. Rayabarapu and C. H. Cheng, Acc. Chem. Res.,
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P. W. Jeffs and D. G. Lynn, J. Org. Chem., 1975, 40, 2958-2960; (c)
T. Okuno, I. Natsume, K. Sawai, K. Sawamura, A. Furusaki and T.
Matsumoto, Tetrahedron Lett., 1983, 24, 5653-5656; (d) S. E.
Snyder, F. A. Aviles-Garay, R. Chakraborti, D. E. Nichols, V. J.
Watts and R. B. Mailman, J. Med. Chem., 1995, 38, 2395-2409; (e)
T. J. Hsieh, F. R. Chang, Y. C. Chia, C. Y. Chen, H. C. Lin, H. F. Chiu
and Y. C. Wu, J. Nat. Prod., 2001, 64, 1157-1161; (f) A. Idris, M. A.
Tantry, B. A. Ganai, A. N. Kamili and J. S. Williamson, Phytochem.
Lett., 2015, 11, 264-269.
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