Enantioselective palladium-catalyzed allylic substitution of sodium benzotriazolide

Article abstract of DOI:10.1002/ejoc.201100879

Chiral allylic benzotriazole-containing regioisomers 4 and 5 were synthesized by enantioselective palladium-catalyzed allylation of sodium benzotriazolide with a range of allylic carbonates in 50-89 % yields, regioselectivities of 2.2:1 to 1:3.4, and ee values of up to 95 %.

Full text of DOI:10.1002/ejoc.201100879

FULL PAPER
DOI: 10.1002/ejoc.201100879
Enantioselective Palladium-Catalyzed Allylic Substitution of Sodium
Benzotriazolide
[
a]
[b]
[a]
[a]
[a]
Wei Liu, Dazhi Zhang, Shengcai Zheng, Yinshuang Yue, Dongge Liu, and
Xiaoming Zhao*[
a]
Keywords: Nitrogen heterocycles / Asymmetric catalysis / Allylation / Palladium / N,P ligands / Regioselectivity
Chiral allylic benzotriazole-containing regioisomers 4 and 5
were synthesized by enantioselective palladium-catalyzed
allylation of sodium benzotriazolide with a range of allylic
carbonates in 50–89% yields, regioselectivities of 2.2:1 to
1:3.4, and ee values of up to 95%.
The palladium-catalyzed asymmetric allylic alkylation and a polar solvent in solution. However, 3aЈ is by 4 kcal/
[
12]
(
AAA) has been developed as a useful tool for the prepara- mol more stable than 3a in the gas phase. An initial study
[1]
tion of chiral allylic compounds and, during the past sev- on the palladium-catalyzed allylation of BtH with cinnamyl
eral decades, a wide range of nitrogen nucleophiles have ethyl carbonate as an allylating agent provided good yields
been studied in Tsuji–Trost allylation reactions. In this con- of allylic Bt-containing regioisomers, albeit with poor regio-
text, the use of benzotriazole (BtH) as a pronucleophile in selectivities. Herein, we report the formation of chiral Bt-
asymmetric reactions of this type has not yet been reported. containing allylic compounds through Pd-catalyzed asym-
The asymmetric reaction of BtH has been extensively inves- metric allylation of sodium benzotriazolide (BtNa) with
tigated for organocatalytic applications,[ and the alumi- structurally diverse allyl carbonates.
num-catalyzed enantioselective Michael reaction has also
[
2]
[
13]
3]
[
4]
been described. In addition, Bt-containing compounds
may have a broad potential in drug discovery and organic Results and Discussion
[
5]
synthesis, and, as a result, new synthetic methods for the
preparation of chiral Bt-substituted compounds is the sub-
In an exploratory study, we began with a reaction be-
tween BtH, which has two different nucleophilic positions,
and rac-1,3-diphenylallyl ethyl carbonate (2a) in the pres-
ence of [Pd (dba) ·CHCl ] and (S)-PHOX (1a) in tetra-
hydrofuran (THF) at room temperature under argon; un-
fortunately, under these conditions, a complex mixture of
products was obtained. Interestingly, when BtNa was used
rather than BtH under the same reaction conditions, a mix-
ture of allylic N-1 regioisomer 4a and N-2 regioisomer 5a
was achieved in overall 62% yield with 77% ee of 4a and
[6]
ject of considerable interest. Benzotriazole, which is an
important fragment of many pharmaceuticals,[ contains a
7]
2
3
3
relatively acidic N–H bond (pK = 8.6) and exists in two
a
[
8]
tautomeric forms (3a and 3aЈ) in solution (Scheme 1).
Scheme 1. Tautomers of benzotriazole in solution.
94% of 5a, although unsurprisingly with a low regioselec-
[
9]
tivity (4a/5a = 1:1.2; Table 1, Entry 1), which is in agree-
Tautomer 3a has a greater aromatic character and pre-
[9]
ment with results obtained with the palladium-catalyzed al-
dominates in the equilibrium both in solution and in the
solid phase. The repulsion of electronic pairs between the
N-2 and N-1 atoms has a destabilizing effect. The larger
dipolar moment of 3a favors the interactions between
benzotriazole molecules in the solid state and between 3a
[
13]
[
10]
lylation of BtH. Solvent screening revealed that THF was
an optimal solvent (Table 1, Entry 1); poor results were ob-
tained when the reaction was conducted in dioxane, diethyl
ether, or toluene (Table 1, Entries 2–3, 5). The reaction in
dichloromethane gave rise to moderate yields and ee values
of 4a and 5a (Table 1, Entry 4). Additionally, varyiation of
the ratio of 2a/3b was found to have a considerable influ-
ence on the outcome of the allylation reaction; it was found
that a twofold excess of 3b produced the highest yield and
ee of 4a and 5a (Table 1, Entries 1, 6, 7). Change of the
reaction temperature had a drastic effect on the efficiency,
regioselectivity, and enantioselectivity (Table 1, Entries 1, 8,
[11]
[
[
a] Department of Chemistry, Tongji University,
1239 Siping Lu, Shanghai 200092, P. R. China
b] Department of Organic Chemistry, School of Pharmacy,
Second Military Medical University,
Shanghai 200433, P. R. China
Fax: +86-21-65981376
E-mail: xmzhao08@mail.tongji.edu.cn
Supporting information for this article is available on the
WWW under http://dx.doi.org/10.1002/ejoc.201100879.
6288
© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2011, 6288–6293

Enantioselective Allylic Substitution of Sodium Benzotriazolide
Table 1. Optimizing reaction conditions for Pd-catalyzed asymmetric allylation of BtNa.[a]
Entry
Ligand
2a/3b
Solvent
T [°C]
Overall yield [%][b]
4a/5a
ee [%][c]
4a
5a
1
2
3
4
5
6
7
8
9
1a
1a
1a
1a
1a
1a
1a
1a
1a
1b
1c
1d
1e
1f
1.2:1
1.2:1
1.2:1
1.2:1
1.2:1
2:1
1:2
1:2
1:2
1:2
1:2
1:2
1:2
1:2
THF
dioxane
r.t.
r.t.
r.t.
r.t.
r.t.
r.t.
r.t.
0
62
42
28
67
30
60
72
46
64
65
67
68
53
38
1:1.2
1:1.2
1.5:1
2:1
77
–
–
41
–
77
77
20
75
4
94
Et
CH
2
O
Cl
2
2
59
toluene
THF
THF
THF
THF
THF
THF
THF
THF
THF
2:1
1:1.2
1:1.3
1:1.3
1:1.2
1:1.1
1:1.1
1.2:1
1.5:1
1:1.1
94
91
65
85
11
80
75
35
14
35
1
1
1
1
0
1
2
3
r.t.
r.t.
r.t.
r.t.
r.t.
67
34
9
[
d]
1
4
0
[
a] Reagents and conditions: 3b (0.2 mmol, 1.0 equiv.), catalyst (5 mol-%), solvent (2 mL), argon. [b] Isolated yield. [c] Determined by
HPLC analysis using Diacel CHIRALPAK AD-H. [d] Reaction time 60 h.
Scheme 2. Chiral ligands 1a–f.
9
). Further investigations were performed with a range of selectivity. Ligand 1a gave the best results (overall 72%
[14–16]
[14–16]
[14–16]
[17]
chiral ligands, including 1a,
1b,
1c,
1d,
yield with 77% ee of 4a and 91% ee of 5a) in favor of the
[18]
[19]
1e, and Trost ligand 1f (Scheme 2) to evaluate how the N-2 regioisomer 5a (4a/5a = 1:1.3; Table 1, Entry 7). The
structural variation of the ligands may affect the enantio- palladium complexes generated from 1b and 1d–f gave
Table 2. Pd-catalyzed asymmetric allylation of BtNa with various allyl carbonates.[a]
Entry
R
Product
Overall yield [%][b]
4/5
ee [%][c]
4
5
1
2
3
4
5
Ph
2-MeC
3-MeC
4-MeC
4a, 5a
4b, 5b
4c, 5c
4d, 5d
4e, 5e
4f, 5f
72
69
89
87
60
50
80
73
1:1.3
1.8:1
1.3:1
2.2:1
2:1
1:1
1:3.4
1:1.9
77
–46
95
65
40
44
–72
–61
91
–72
95
80
68
73
78
71
6
6
6
H
H
H
4
4
4
4-BrC
6
H
4
[
d]
6
2-naphthyl
[
e]
e]
7
8
Et
Me
4g, 5g
4h, 5h
[
[
[
a] Reagents and conditions: carbonate 2a–h (0.2 mmol, 1.0 equiv.), 3b (0.4 mmol, 2.0 equiv.), catalyst (5 mol-%), THF (2 mL), argon.
b] Isolated yield. [c] Determined by HPLC analysis using a chiral stationary phase. [d] OCO Et was replaced by OAc due to decomposi-
2
tion. [e] 10 mol-% of catalyst was used; the ratio of 2/3b was 2:1.
Eur. J. Org. Chem. 2011, 6288–6293
© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
6289

X. Zhao et al.
FULL PAPER
either poor yields or ee values (Table 1, Entries 10, 12–14). by rotary evaporation. The white solid was washed with CH
2
Cl
2
,
]
and the solvent was removed under vacuum. [Pd (dba) ·CHCl
2
3
3
Use of ligand 1c led to the formation of 4a (32% yield and
(
0.01 mmol, 11.5 mg) and ligand (0.02 mmol) were dissolved in
67% ee) and 5a (35% yield and 80% ee) with a 1:1 ratio of
THF (2.0 mL) and stirred in a dry Schlenk tube filled with argon
for 30 min. Allylic carbonate 2 (0.20 mmol) and sodium benzotri-
azolide (0.40 mmol, 56.4 mg) were added, and the reaction mixture
was stirred at room temperature. The crude reaction mixture was
filtered through Celite, and the solvent was removed under reduced
pressure. The crude residue was purified by flash column
4a/5a (Table 1, Entry 9). Therefore, the conditions pre-
sented in Table 1, Entry 7 were chosen as the standard.
With the optimized reaction conditions in hand, the
scope of the enantioselective Pd-catalyzed allylation of
BtNa was further examined with a range of allyl carbonates
(Table 2). It can be seen that the variation of substituents chromatography (ethyl acetate/petroleum ether, 1:20) to give the
in the symmetrical allyl carbonates 2a–h strongly influences desired products.
both the regio- and enantioselectivity. The reaction of di-
(
E)-1,3-Di-m-tolylallyl Ethyl Carbonate (2c): Yield: 1.0 g (70%).
arylallyl carbonates with electron-donating or electron-at-
tracting groups (o-Me, m-Me, p-Me; or p-Br) on the phenyl
ring gave Bt-substituted regioisomers (4b–e and 5b–e) in
1
Colorless liquid. H NMR (400 MHz, CDCl
3
): δ = 7.26–7.21 (m,
3
1
6
H), 7.20–7.16 (m, 3 H), 7.12 (d, J = 6.7 Hz, 1 H), 7.07–7.02 (m,
H), 6.65 (d, J = 15.8 Hz, 1 H), 6.34 (dd, J = 15.3, 6.5 Hz, 1 H),
.21 (d, J = 6.8 Hz, 1 H), 4.19 (qd, J = 6.3, 4.3 Hz, 2 H), 2.35 (s,
60–89% overall yields and 40–95% ee, with regioselectivi-
1
3
ties in the range 2.3:1–1.8:1, except for bis(2-naphthyl)allyl 3 H), 2.31 (s, 3 H), 1.29 (t, J = 7.1 Hz, 3 H) ppm. C NMR
carbonate, which gave a 1:1 ratio of 4f/5f (Table 2, En- (100 MHz, CDCl ): δ = 154.5, 138.8, 138.4, 138.2, 136.1, 133.0,
tries 2–6). The reaction of bis(phenyl- and alkyl)allyl carb- 129.2, 129.0, 128.6, 128.5, 127.7, 127.5, 126.9, 124.1, 124.0, 80.2,
onates led to the formation of the corresponding Bt-con-
taining regioisomers (4a, 4g, 4h and 5a, 5g, 5h) in 72–80%
overall yields and 61–91% ee, with regioselectivities in the
range of 1:1.9–1:3.4. It should be noted that diarylallyl
carbonate 2c, with a meta-methyl group on the phenyl rings,
3
6
4.1, 21.5, 21.4, 14.3 ppm. MS (EI): m/z (%) = 220 (100), 310
+
+
22 3
[M] . HRMS (EI): calcd. for C20H O [M] 310.1569; found
3
1
4
10.1570. IR (KBr): ν˜ max = 3037, 2917, 2847, 1650, 1606, 1508,
457, 1378, 1270, 1235, 1156, 1140, 1083, 973, 916, 811, 792, 740,
–
1
98 cm .
gave rise to both 4a and 5a with the highest ee value (95% (E)-1,3-Bis(4-bromophenyl)allyl Ethyl Carbonate (2e): Yield: 1.2 g
1
ee; Table 2, Entry 3). Further study on this reaction indi- (90%). Yellow liquid. H NMR (400 MHz, CDCl
3
): δ = 7.50 (d, J
=
8.4 Hz, 2 H), 7.42 (d, J = 8.3 Hz, 2 H), 7.29 (d, J = 8.3 Hz, 2
H), 7.22 (d, J = 8.4 Hz, 2 H), 6.59 (d, J = 15.8 Hz, 1 H), 6.30 (dd,
J = 15.8, 6.7 Hz, 1 H), 6.18 (d, J = 6.7 Hz, 1 H), 4.20 (qd, J = 7.1,
.1 Hz, 2 H), 1.30 (t, J = 7.1 Hz, 3 H) ppm. C NMR (100 MHz,
CDCl ): δ = 154.3, 137.6, 134.8, 132.1, 131.9, 131.8, 128.8, 128.3,
27.2, 122.6, 122.2, 79.0, 64.4, 14.3 ppm. MS (EI): m/z (%) = 269
cated that no isomerization occurred between 5a and 4a
with [Pd (dba) ·CHCl ] and 1a in THF at room tempera-
2
3
3
ture within 12 h.
1
3
3
3
1
(
Conclusions
+
+
2 3
100), 438 [M] . HRMS (EI): calcd. for C18H16Br O [M]
4
1
5
37.9466; found 437.9469. IR (KBr): ν˜ max = 2986, 2917, 1742,
We have developed an efficient [Pd (dba) ·CHCl ]/(S)-
PHOX (1a) catalyst system for the asymmetric allylic amin-
ation of benzotriazole with a range of carbonates. The al-
2
3
3
486, 1406, 1368, 1302, 1242, 1074, 1004, 960, 807, 849, 846, 830,
–
1
64, 510 cm .
lylic Bt-containing regioisomers were obtained in good General Procedure for the Pd-Catalyzed Asymmetric Allylic Alk-
overall yields with regioselectivities in the range of 2.2:1– ylation of Benzotriazole: [Pd (dba) ·CHCl ] (0.01 mmol, 11.5 mg)
:3.4 and ee of up to 95%. To the best of our knowledge, and ligand (0.02 mmol) were dissolved in THF (2.0 mL) and stirred
2
3
3
1
in a dry Schlenk tube filled with argon for 30 min. Allylic carbonate
(0.20 mmol) and sodium benzotriazolide (0.40 mmol, 56.4 mg)
this is the first example of a transition-metal-catalyzed
asymmetric allylation of BtH. Further studies aimed at im-
proving the regioselectivity and enantioselectivity of this
AAA is in progress.
2
were added, and the reaction mixture was stirred at room tempera-
ture. The crude reaction mixture was filtered through Celite, and
the solvent was removed under reduced pressure. The crude residue
was purified by flash column chromatography (ethyl acetate/petro-
leum ether, 1: 20) to give the desired products.
Experimental Section
General: H and 13C NMR spectra were recorded as solutions in
(
E)-1-(1,3-Diphenylallyl)-1H-benzo[d][1,2,3]triazole (4a): Yield:
1
1
1
9.9 mg (32%). White solid; m.p. 169–170 °C. H NMR (400 MHz,
CDCl ): δ = 8.15–8.08 (m, 1 H), 7.46–7.40 (m, 3 H), 7.39–7.36 (m,
H), 7.36–7.27 (m, 5 H), 7.02 (dd, J = 15.9, 7.2 Hz, 1 H), 6.80 (d,
CDCl
3
with a Bruker NMR (400 MHz) spectrometer. The chemical
Si internal
3
shifts are reported in δ units downfield from the Me
reference. Optical rotations were determined with a JASCO P-2200
instrument. HPLC analyses were carried out on chiral columns
4
5
13
J = 7.2 Hz, 1 H), 6.63 (d, J = 15.7 Hz, 1 H) ppm. C NMR
100 MHz, CDCl ): δ = 146.5, 137.9, 135.8, 134.6, 132.5, 129.1,
28.7, 128.6, 128.5, 127.4, 127.3, 126.9, 125.6, 124.0, 120.2, 110.4,
(
1
6
3
(
Chiralcel AD-H, OJ-H) with a Shimadzu 150 instrument fitted
with a multi-wavelength detector. Low-resolution electron-impact
EI) mass spectra were obtained with an Agilent MSD Chem-
+
5.6 ppm. MS (EI): m/z (%) =193 (100), 311 [M] . HRMS (EI):
(
+
calcd. for C21
17 3
H N [M] 311.1422; found 311.1423. IR (KBr): ν˜ max
station, and high-resolution mass spectra were obtained with a Fin-
nigan VG Platform or a Finnigan MAT 95S. Carbonates 2a–h were
prepared according to known procedures.[
=
3062, 3015, 2923, 1655, 1448, 1381, 1273, 1223, 1153, 1064, 966,
–1
7
42, 691, 532 cm . The enantiomeric excess of the product (77%)
was determined by HPLC analysis (254 nm, 25 °C): t = 14.24
(minor), 18.67 min (major) [Diacel CHIRALPAK AD-H
2a]
R
Sodium Benzotriazolide (3b): BtH (6.0 g, 0.1 mol) was dissolved in
THF and cooled to 0 °C in an ice bath. NaH (1.2 g, 0.1 mol) was
added, and the mixture was stirred for 2 h, then THF was removed
2
0
(0.46 cmϫ25 cm); hexane/2-propanol, 80:20; 1.0 mL/min]. [α]
D
=
–21.0 (c = 1.0, CHCl ).
3
6290
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© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2011, 6288–6293

Enantioselective Allylic Substitution of Sodium Benzotriazolide
E)-2-(1,3-Diphenylallyl)-2H-benzo[d][1,2,3]triazole (5a): Yield:
(
(E)-2-(1,3-Di-m-tolylallyl)-2H-benzo[d][1,2,3]triazole (5c): Yield:
26.4 mg (39%). White solid; m.p. 65–66 °C. H NMR (400 MHz,
1
1
2
4.9 mg (40%). White solid; m.p. 128–129 °C. H NMR (400 MHz,
CDCl
H), 7.46–7.39 (m, 5 H), 7.39–7.27 (m, 4 H), 7.09 (dd, J = 15.9, 3.0 Hz, 2 H), 7.29–7.26 (m, 1 H), 7.25–7.16 (m, 5 H),7.13–7.07 (m,
.9 Hz, 1 H), 6.79 (d, J = 8.0 Hz, 1 H), 6.71 (d, J = 15.8 Hz, 1 H) 2 H), 7.03 (dd, J = 15.8, 7.9 Hz, 1 H), 6.70 (d, J = 8.0 Hz, 1 H),
3
3
): δ = 7.97–7.90 (dd, J = 6.6, 3.1 Hz, 2 H), 7.52–7.46 (m, 3 CDCl ): δ = 7.89 (dd, J = 6.6, 3.0 Hz, 2 H), 7.37 (dd, J = 6.6,
7
13
13
ppm. C NMR (100 MHz, CDCl
3
): δ = 144.4, 138.4, 135.9, 134.6,
6.64 (d, J = 15.8 Hz, 1 H), 2.32 (s, 3 H), 2.31 (s, 3 H) ppm.
): δ = 144.4, 138.7, 138.4, 138.2, 135.9,
2.6 ppm. MS (EI): m/z (%) =193 (100), 311 [M] . HRMS (EI): 134.5, 129.4, 129.2, 128.8, 128.6, 128.0, 127.6, 126.4, 126.0, 124.5,
C
1
7
28.9, 128.7, 128.6, 128.4, 127.4, 127.0, 126.5, 126.2, 118.3, NMR (100 MHz, CDCl
3
+
+
calcd. for C21
H
17
N
3
[M] 311.1422; found 311.1420. IR (KBr): ν˜ max
124.2, 118.4, 72.7, 21.5, 21.4 ppm. MS (EI): m/z (%) =221 (100),
+
+
=
3062, 3021, 2923, 1653, 1492, 1448, 1381, 1308, 1201, 967, 887,
339 [M] . HRMS (EI): calcd. for C23
21 3
H N [M] 339.1735; found
–1
745, 694, 548, 482 cm . The enantiomeric excess of the product
339.1737. IR (KBr): ν˜ max = 3060, 2917, 2850, 1711, 1612, 1492,
–
1
(
91%) was determined by HPLC analysis (254 nm, 25 °C): t
R
=
1451, 1369, 1277, 1229, 1153, 1068, 960, 754, 447 cm . The enan-
tiomeric excess of the product (95%) was determined by HPLC
1
0.52 (minor), 11.35 min (major) [Diacel CHIRALPAK AD-H
2
0
(0.46 cmϫ25 cm); hexane/2-propanol, 80:20; 1.0 mL/min]. [α]
D
=
R
analysis (254 nm, 25 °C): t = 9.46 (minor), 11.81 min (major) [Di-
–
3
55.0 (c = 1.0, CHCl ).
acel CHIRALPAK AD-H (0.46 cmϫ25 cm); hexane/2-propanol,
2
0
D 3
90:10; 1.0 mL/min]. [α] = –10.9 (c = 1.0, CHCl ).
(E)-1-(1,3-Di-o-tolylallyl)-1H-benzo[d][1,2,3]triazole (4b): Yield:
1
2
9.8 mg (44%). White solid; m.p. 146–147 °C. H NMR (400 MHz,
CDCl ): δ = 8.13 (dd, J = 5.7, 3.0 Hz, 1 H), 7.60–7.54 (m, 1 H),
.38 (t, J = 3.8 Hz, 3 H), 7.34–7.25 (m, 4 H), 7.24–7.13 (m, 3 H),
.02 (d, J = 6.2 Hz, 1 H), 6.84 (dd, J = 15.7, 6.2 Hz, 1 H), 6.66 (d,
(
4
E)-1-(1,3-Di-p-tolylallyl)-1H-benzo[d][1,2,3]triazole (4d): Yield:
0.7 mg (60%). White solid; m.p. 136–137 °C. H NMR (400 MHz,
3
1
7
7
CDCl ): δ = 8.07 (d, J = 7.8 Hz, 1 H), 7.37–7.26 (m, 5 H), 7.20 (d,
3
J = 7.7 Hz, 2 H), 7.17–7.08 (m, 4 H), 6.91 (dd, J = 15.8, 7.1 Hz, 1
1
3
J = 15.8 Hz, 1 H), 2.38 (s, 3 H), 2.23 (s, 3 H) ppm. C NMR
100 MHz, CDCl ): δ = 146.4, 136.5, 135.8, 135.8, 135.1, 132.8,
31.8, 131.2, 130.4, 128.8, 128.3, 127.6, 127.3, 126.9, 126.7, 126.3,
26.1, 124.0, 120.2, 110.5, 62.9, 19.7, 19.3 ppm. MS (EI): m/z (%)
H), 6.72 (d, J = 7.1 Hz, 1 H), 6.54 (d, J = 15.8 Hz, 1 H), 2.32 (s, 6
(
1
1
=
3
13
3
H) ppm. C NMR (100 MHz, CDCl ): δ = 146.5, 138.4, 135.0,
1
1
3
3
1
34.3, 133.1, 132.5, 129.7, 129.4, 127.3, 127.2, 126.8, 124.7, 123.9,
20.2, 110.6, 65.5, 21.3, 21.2 ppm. MS (EI): m/z (%) =221 (100),
+
+
221 (100), 339 [M] . HRMS (EI): calcd. for C23
H
21
N
3
[M]
+
+
21 3
39 [M] . HRMS (EI): calcd. for C23H N [M] 339.1735; found
3
1
39.1735; found 339.1737. IR (KBr): ν˜ max = 3031, 2910, 2857,
736, 1612, 1486, 1448, 1321, 1267, 960, 795, 687, 441 cm . The
39.1736. IR (KBr): ν˜ max = 3028, 2923, 2860, 1742, 1615, 1511,
–
1
–1
451, 1384, 1273, 1156, 969, 808, 748, 498 cm . The enantiomeric
enantiomeric excess of the product (–46%) was determined by
HPLC analysis (254 nm, 25 °C): t = 6.20 (major), 6.63 min
minor) [Diacel CHIRALPAK AD-H (0.46 cmϫ25 cm); hexane/2-
excess of the product (65%) was determined by HPLC analysis
254 nm, 25 °C): t = 23.29 (minor); 35.12 min (major) [Diacel
CHIRALPAK AD-H (0.46 cmϫ25 cm); hexane/2-propanol,
R
(
R
(
2
0
propanol, 90:10; 1.0 mL/min]. [α]
D
= 34.4 (c = 1.0, CHCl
3
).
20
80:20; 1.0 mL/min]. [α]
D 3
= –29.6 (c = 1.0, CHCl ).
(
1
E)-2-(1,3-Di-o-tolylallyl)-2H-benzo[d][1,2,3]triazole (5b): Yield:
1
(E)-2-(1,3-Di-p-tolylallyl)-2H-benzo[d][1,2,3]triazole (5d): Yield:
7.0 mg (25%). White solid; m.p. 71–72 °C. H NMR (400 MHz,
): δ = 7.89 (dd, J = 6.5, 3.1 Hz, 2 H), 7.54 (dd, J = 5.2,
.8 Hz, 1 H), 7.40–7.33 (m, 3 H), 7.22 (dd, J = 7.2, 5.1 Hz, 3 H),
1
1
8.3 mg (27%). White solid; m.p. 101–102 °C. H NMR (400 MHz,
CDCl ): δ = 7.88 (dd, J = 6.5, 2.9 Hz, 2 H), 7.36 (dd, J = 6.6,
.8 Hz, 2 H), 7.34–7.28 (m, 4 H), 7.16 (d, J = 7.8 Hz, 2 H), 7.12
d, J = 7.7 Hz, 2 H), 6.97 (dd, J = 15.8, 7.9 Hz, 1 H), 6.70 (d, J =
CDCl
3
3
3
7
6
2
.18–7.10 (m, 3 H), 6.98 (d, J = 6.9 Hz, 1 H), 6.85 (dd, J = 15.6,
.9 Hz, 1 H), 6.77 (d, J = 15.7 Hz, 1 H), 2.43 (s, 3 H), 2.26 (s, 3
(
1
3
1
3
7.9 Hz, 1 H), 6.62 (d, J = 15.8 Hz, 1 H), 2.32 (s, 6 H) ppm.
C
H) ppm. C NMR (100 MHz, CDCl
1
1
=
3
1
3
): δ = 144.3, 136.6, 135.9,
35.9, 135.1, 131.9, 130.9, 130.4, 128.6, 128.2, 127.3, 127.2, 126.7,
26.4, 126.2, 126.2, 118.3, 69.4, 19.7, 19.4 ppm. MS (EI): m/z (%)
NMR (100 MHz, CDCl
3
): δ = 144.3, 138.4, 138.3, 135.6, 134.3,
1
33.2, 129.5, 129.3, 127.4, 126.9, 126.3, 125.3, 118.3, 72.5, 21.3,
+
+
+
21.2 ppm. MS (EI): m/z (%) =221 (100), 339 [M] . HRMS (EI):
calcd. for C23
21 3
221 (100), 339 [M] . HRMS (EI): calcd. for C23H N [M]
+
21 3
H N [M] 339.1735; found 339.1736. IR (KBr): ν˜ max
39.1735; found 339.1738. IR (KBr): ν˜ max = 3322, 2926, 2853,
–1
= 3021, 2920, 1654, 1518, 1451, 1372, 1318, 1258, 1182, 970, 887,
732, 1457, 1254, 1004, 884, 745, 435 cm . The enantiomeric ex-
–
1
7
98, 745, 504 cm . The enantiomeric excess of the product (80%)
was determined by HPLC analysis (214 nm, 25 °C): t = 7.52
minor), 8.26 min (major) [Diacel CHIRALPAK OD-H
cess of the product (–72%) was determined by HPLC analysis
254 nm, 25 °C): t = 5.42 (major), 12.51 min (minor) [Diacel CHI-
R
(
R
(
RALPAK AD-H (0.46 cmϫ25 cm); hexane/2-propanol, 90:10;
1
2
0
.0 mL/min]. [α]2
0
(0.46 cmϫ25 cm); hexane/2-propanol, 90:10; 1.0 mL/min]. [α]
D
=
D 3
= 20.8 (c = 1.0, CHCl ).
–
19.0 (c = 1.0, CHCl ).
3
(
E)-1-(1,3-Di-m-tolylallyl)-1H-benzo[d][1,2,3]triazole (4c): Yield:
1
3
3.9 mg (50%). White solid; m.p. 100–101 °C. H NMR (400 MHz,
CDCl ): δ = 8.13 (d, J = 7.8 Hz, 1 H), 7.42–7.35 (m, 3 H), 7.30–
.22 (m, 4 H), 7.19–7.10 (m, 4 H), 7.01 (dd, J = 15.8, 7.2 Hz, 1 H),
.75 (d, J = 7.2 Hz, 1 H), 6.60 (d, J = 15.8 Hz, 1 H), 2.36 (s, 3 H),
.34 (s, 3 H) ppm. 13C NMR (100 MHz, CDCl
): δ = 146.5, 138.9, (d, J = 8.2 Hz, 2 H), 7.20 (d, J = 8.3 Hz, 2 H), 6.95 (dd, J = 15.9,
(E)-1-[1,3-Bis(4-bromophenyl)allyl]-1H-benzo[d][1,2,3]triazole (4e):
Yield: 37.4 mg (40%). White solid; m.p. 157–158 °C. 1H NMR
3
7
6
2
(400 MHz, CDCl
3
): δ = 8.12 (d, J = 8.0 Hz, 1 H), 7.51 (d, J =
8.3 Hz, 2 H), 7.46 (d, J = 8.3 Hz, 2 H), 7.44–7.33 (m, 3 H), 7.28
3
1
38.3, 137.9, 135.8, 134.5, 132.5, 129.3, 129.2, 128.9, 128.6, 128.0,
7.0 Hz, 1 H), 6.69 (d, J = 7.0 Hz, 1 H), 6.54 (d, J = 15.8 Hz, 1 H)
ppm. C NMR (100 MHz, CDCl ): δ = 146.5, 136.7, 134.5, 133.7,
3
1
3
127.5, 127.3, 125.5, 124.4, 124.1, 124.0, 120.2, 110.5, 65.6, 21.5,
+
21.4 ppm. MS (EI): m/z (%) =221 (100), 339 [M] . HRMS (EI): 132.3, 132.3, 131.9, 129.0, 128.4, 127.6, 125.9, 124.2, 122.8, 122.6,
+
+
calcd. for C23
=
7
H
21
N
3
[M] 339.1735; found 339.1737. IR (KBr): ν˜ max
120.4, 110.0, 64.7 ppm. MS (EI): m/z (%) =349 (100), 467 [M] .
+
3019, 2933, 2847, 1609, 1486, 1451, 1267, 1372, 1156, 1061, 967,
HRMS (EI): calcd. for C23
H15Br
2
N
3
[M] 466.9633; found
–1
86, 741, 688, 434 cm . The enantiomeric excess of the product
466.9639. IR (KBr): ν˜ max = 3056, 2923, 2847, 1660, 1584, 1486,
(
1
95%) was determined by HPLC analysis (254 nm, 25 °C): t
R
=
1448, 1406, 1264, 1156, 1064, 1001, 963, 811, 748, 700, 545,
–
1
1.16 (minor), 14.91 min (major) [Diacel CHIRALPAK AD-H
491 cm . The enantiomeric excess of the product (41%) was deter-
mined by HPLC analysis (254 nm, 25 °C): t = 17.94 (minor),
30.25 min (major) [Diacel CHIRALPAK AD-H (0.46 cmϫ25 cm);
2
0
(0.46 cmϫ25 cm); hexane/2-propanol, 80:20; 1.0 mL/min]. [α]
D
=
R
–
3
22.2 (c = 1.0, CHCl ).
Eur. J. Org. Chem. 2011, 6288–6293
© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
6291

X. Zhao et al.
FULL PAPER
hexane/2-propanol, 70:30; 1.0 mL/min]. [α]20
–1
D
= –55.6 (c = 1.0,
1278, 1200, 1089, 978, 750, 740 cm . The enantiomeric excess of
the product (–72%) was determined by HPLC analysis (214 nm,
CHCl ).
3
2
5 °C): t
R
= 6.79 (major), 7.84 min (minor) [Diacel CHIRALPAK
(
E)-2-[1,3-Bis(4-bromophenyl)allyl]-2H-benzo[d][1,2,3]triazole (5e):
Yield: 18.7 mg (20%). White solid; m.p. 139–140 °C. 1H NMR
400 MHz, CDCl ): δ = 7.91 (dd, J = 6.6, 3.1 Hz, 2 H), 7.51 (d, J
8.5 Hz, 2 H), 7.47 (d, J = 8.4 Hz, 2 H), 7.42 (dd, J = 6.6, 3.1 Hz,
H), 7.32 (d, J = 8.2 Hz, 2 H), 7.30 (d, J = 8.5 Hz, 2 H), 7.00 (dd, 26.7 mg (62%). Colorless liquid. H NMR (400 MHz, CDCl ): δ =
AD-H (0.46 cmϫ25 cm); hexane/2-propanol, 90:10; 1.0 mL/min].
[α] = 20.5 (c = 1.0, CHCl ).
D 3
2
0
(
=
2
3
(E)-2-(Hept-4-en-3-yl)-2H-benzo[d][1,2,3]triazole
(5g):
Yield:
1
3
J = 15.9, 7.7 Hz, 1 H), 6.71 (d, J = 7.7 Hz, 1 H), 6.60 (d, J =
7.88 (dd, J = 6.5, 3.1 Hz, 2 H), 7.37 (dd, J = 6.5, 3.1 Hz, 2 H),
5.91–5.78 (m, 2 H), 5.23 (dd, J = 14.7, 6.9 Hz, 1 H), 2.38–2.24 (m,
1 H), 2.24–2.10 (m, 1 H), 2.07 (dt, J = 12.3, 6.2 Hz, 2 H), 0.99 (t, J
1
1
1
5.8 Hz, 1 H) ppm. 13C NMR (100 MHz, CDCl
3
): δ = 144.4, 137.1,
34.6, 133.7, 132.1, 131.9, 129.2, 128.5, 126.7, 126.4, 122.9, 122.5,
+
13
18.3, 71.7 ppm. MS (EI): m/z (%) = 349 (100), 467 [M] . HRMS
= 7.4 Hz, 3 H), 0.86 (t, J = 7.4 Hz, 3 H) ppm. C NMR (100 MHz,
+
(EI): calcd. for C23
H15Br
2
N
3
[M] 466.9633; found 466.9636. IR
CDCl ): δ = 144.0, 136.9, 126.9, 126.0, 118.1, 71.3, 28.9, 25.2, 13.1,
3
+
(
1
KBr): ν˜ max = 3066, 2920, 2841, 1732, 1598, 1486, 1410, 1308, 1258,
261, 1188, 1071, 1004, 969, 890, 821, 738, 540, 494 cm . The en-
10.6 ppm. MS (EI): m/z (%) = 143 (100), 215 [M] . HRMS (EI):
calcd. for C H N [M] 215.1422; found 215.1423. IR (KBr): ν˜
–1
+
1
3
17
3
max
antiomeric excess of the product (68%) was determined by HPLC
analysis (276 nm, 25 °C): t = 6.85 (minor), 7.69 min (major) [Di-
acel CHIRALPAK OD-H (0.46 cmϫ25 cm); hexane/2-propanol,
= 3003, 2989, 2910, 2860, 2801, 1720, 1550, 1440, 1368, 1250, 1090,
–
1
R
1020, 783, 660 cm . The enantiomeric excess of the product
(78%) was determined by HPLC analysis (254 nm, 25 °C): tR
7.92 (minor), 9.47 min (major) [Diacel CHIRALPAK IC
=
0:10; 1.0 mL/min]. [α]2
0
9
D 3
= –26.2 (c = 1.0, CHCl ).
2
0
(
0.46 cmϫ25 cm); hexane/2-propanol, 99:1; 1.0 mL/min]. [α]
D
=
(
E)-1-[1,3-Bis(naphthalen-2-yl)allyl]-1H-benzo[d][1,2,3]triazole (4f):
1
40.7 (c = 1.0, CHCl ).
3
Yield: 20.6 mg (25%). White solid; m.p. 160–161 °C. H NMR
400 MHz, CDCl ): δ = 8.11 (dd, J = 5.3, 2.6 Hz, 1 H), 7.84 (d, J
3.4 Hz, 2 H), 7.82–7.72 (m, 6 H), 7.65 (d, J = 8.5 Hz, 1 H), 7.49
dd, J = 5.4, 2.7 Hz, 2 H), 7.46–7.31 (m, 6 H), 7.19 (dd, J = 15.8,
.9 Hz, 1 H), 6.97 (d, J = 6.9 Hz, 1 H), 6.78 (d, J = 15.8 Hz, 1 H)
(
=
(
6
3
(E)-1-(Pent-3-en-2-yl)-1H-benzo[d][1,2,3]triazole (4h): Yield: 9.4 mg
1
(25%). Colorless liquid. H NMR (400 MHz, CDCl ): δ = 8.06 (d,
3
J = 8.3 Hz, 1 H), 7.55 (d, J = 8.3 Hz, 1 H), 7.45 (t, J = 7.5 Hz, 1
H), 7.35 (t, J = 7.6 Hz, 1 H), 5.84 (dd, J = 15.4, 6.3 Hz, 1 H), 5.74
(dq, J = 18.2, 5.9 Hz, 1 H), 5.49 (quint, J = 6.4 Hz, 1 H), 1.84 (d,
13
ppm. C NMR (100 MHz, CDCl
3
): δ = 146.6, 135.3, 134.8, 133.5,
1
3
1
1
6
33.4, 133.2, 132.6, 129.2, 128.5, 128.2, 128.1, 127.8, 127.8, 127.5,
J = 7.0 Hz, 3 H), 1.73 (d, J = 6.0 Hz, 3 H) ppm. C NMR
27.3, 126.7, 126.5, 126.4, 125.8, 125.0, 124.1, 123.6, 120.3, 110.5,
(100 MHz, CDCl ): δ = 146.5, 132.2, 130.0, 128.6, 126.9, 123.7,
3
+
5.8 ppm. MS (EI): m/z (%) = 293 (100), 411 [M] . HRMS (EI):
120.1, 110.3, 57.4, 20.1, 17.6 ppm. MS (EI): m/z (%) = 144 (100),
+
+
+
calcd. for C29
H
21
N
3
[M] 411.1735; found 411.1737. IR (KBr): ν˜ max
11 13 3
187 [M] . HRMS (EI): calcd. for C H N [M] 187.1109; found
=
3053, 2932, 2853, 1723, 1593, 1505, 1480, 1394, 1267, 1251, 1077,
187.1108. IR (KBr): ν˜ max = 2980, 2923, 2850, 1606, 1451, 1384,
1267, 1159, 1074, 960, 776, 745 cm . The enantiomeric excess of
–1
–1
9
60, 862, 814, 786, 741, 707, 662, 475 cm . The enantiomeric ex-
cess of the product (44%) was determined by HPLC analysis
254 nm, 25 °C): t = 16.83 (minor), 30.83 min (major) [Diacel
CHIRALPAK AD-H (0.46 cmϫ25 cm); hexane/2-propanol,
the product (–61%) was determined by HPLC analysis (214 nm,
25 °C): tR = 6.86 (major), 7.56 min (minor) [Diacel CHIRALPAK
AD-H (0.46 cmϫ25 cm); hexane/2-propanol, 90:10; 1.0 mL/min].
(
R
0:50; 1.0 mL/min]. [α]2
0
= –8.4 (c = 1.0, CHCl
).
20
D
5
D
3
[α] = 8.3 (c = 1.0, CHCl3).
(
E)-2-[1,3-Bis(naphthalen-2-yl)allyl]-2H-benzo[d][1,2,3]triazole (5f):
(E)-2-(Pent-3-en-2-yl)-2H-benzo[d][1,2,3]triazole
18.0 mg (48%). Colorless liquid. H NMR (400 MHz, CDCl ): δ =
(5h):
Yield:
1
1
Yield: 20.6 mg (25%). White solid; m.p. 122–123 °C. H NMR
400 MHz, CDCl ): δ = 7.95–7.89 (m, 3 H), 7.86–7.74 (m, 7 H), 7.88 (dd, J = 6.5, 3.1 Hz, 2 H), 7.37 (dd, J = 6.5, 3.1 Hz, 2 H), 5.90
.68 (d, J = 8.6 Hz, 1 H), 7.54 (d, J = 8.5 Hz, 1 H), 7.49–7.41 (m, (dd, J = 15.8, 7.2 Hz, 1 H), 5.85–5.75 (m, 1 H), 5.51 (quint, J =
3
(
7
3
4
H), 7.38 (dd, J = 6.6, 3.0 Hz, 2 H), 7.25 (dd, J = 15.4, 7.2 Hz, 1
6.9 Hz, 1 H), 1.82 (d, J = 6.9 Hz, 3 H), 1.73 (d, J = 6.1 Hz, 3 H)
1
3
13
H), 6.97 (d, J = 7.6 Hz, 1 H), 6.85 (d, J = 15.8 Hz, 1 H) ppm.
C
ppm. C NMR (100 MHz, CDCl ): δ = 144.1, 130.2, 129.2, 126.1,
3
NMR (100 MHz, CDCl
3
): δ = 144.5, 135.8, 134.8, 133.5, 133.4,
118.1, 64.7, 21.1, 17.7 ppm. MS (EI): m/z (%) = 187 (100), 187
[M] . HRMS (EI): calcd. for C H N [M] 187.1109; found
11 13 3
+
+
1
1
33.3, 133.3, 128.9, 128.4, 128.3, 128.2, 127.7, 127.4, 126.8, 126.6,
26.5, 126.4, 126.3, 125.0, 123.8, 118.4, 72.8 ppm. MS (EI): m/z
187.1110. IR (KBr): ν
1251, 1080, 1023, 792, 666 cm . The enantiomeric excess of the
product (71%) was determined by HPLC analysis (254 nm, 25 °C):
˜
max
= 2964, 2929, 2863, 1726, 1441, 1378,
+
+
–1
(%) = 293 (100), 411 [M] . HRMS (EI): calcd. for C29
H
21
N
3
[M]
4
1
8
11.1735; found 411.1736. IR (KBr): ν˜ max = 3053, 3027, 2930,
739, 1650, 1619, 1569, 1508, 1441, 1368, 1334, 1226, 1033, 960,
52, 808, 741, 691, 475 cm . The enantiomeric excess of the prod-
tR = 9.50 (major), 10.26 min (minor) [Diacel CHIRALPAK AD-
–1
20
H (0.46 cmϫ25 cm); hexane/2-propanol, 98:2; 1.0 mL/min]. [α]D
48.8 (c = 1.0, CHCl3).
=
uct (78%) was determined by HPLC analysis (254 nm, 25 °C): t
R
=
19.61 (minor), 23.00 min (major) [Diacel CHIRALPAK AD-H
2
0
Supporting Information (see footnote on the first page of this arti-
cle): H and C NMR spectra of new substances and chiral HPLC
charts.
(0.46 cmϫ25 cm); hexane/2-propanol, 50:50; 1.0 mL/min]. [α]
D
=
1
13
3
–28.5 (c = 1.0, CHCl ).
(E)-1-(Hept-4-en-3-yl)-1H-benzo[d][1,2,3]triazole (4g): Yield: 7.7 mg
1
3
(18%). Colorless liquid. H NMR (400 MHz, CDCl ): δ = 8.07 (d,
J = 8.3 Hz, 1 H), 7.55 (d, J = 8.3 Hz, 1 H), 7.45 (t, J = 7.6 Hz, 1 Acknowledgments
H), 7.35 (t, J = 7.6 Hz, 1 H), 5.87–5.71 (m, 2 H), 5.20 (dd, J =
1
=
4.7, 6.7 Hz, 1 H), 2.39–2.22 (m, 1 H), 2.13–2.00 (m, 2 H), 0.97 (t, J
7.4 Hz, 3 H), 0.88 (t, J = 7.4 Hz, 3 H) ppm. 13C NMR (100 MHz,
CDCl ): δ = 146.3, 136.3, 132.4, 126.8, 126.6, 123.7, 120.1, 110.2,
3.9, 27.6, 25.2, 13.2, 10.8 ppm. MS (EI): m/z (%) = 143 (100),
We gratefully acknowledge the Pu Jiang Program of Shanghai
(2010–2013), the Innovative Program of Shanghai Education Com-
mittee (09ZZ36), the National Natural Science Foundation of
China (NSFC) (20942003), the Jiao Gai Program of Department
of Chemistry in Tongji University (2009–2011), the 985 Program
of Tongji University, Key Laboratory of Fluorine Chemistry, the
3
6
2
2
+
+
15 [M] . HRMS (EI): calcd. for C13
15.1424. IR (KBr): ν˜ max = 2990, 2920, 2835, 1705, 1468, 1390,
17 3
H N [M] 215.1422; found
6292
www.eurjoc.org
© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2011, 6288–6293

Enantioselective Allylic Substitution of Sodium Benzotriazolide
Shanghai Institute of Organic Chemistry, the Chinese Academy of
Sciences (2011–2012), the State Key Laboratory of Fine Chemicals,
and the Dalian University of Technology (KF1006) for generous
financial support.
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Received: June 16, 2011
Published Online: August 30, 2011
Eur. J. Org. Chem. 2011, 6288–6293
© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
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