Organocatalyzed regio- and stereoselective diamination of functionalized alkenes

Article abstract of DOI:10.1016/j.tet.2010.04.054

The first organocatalyzed diamination reaction of alkenes with N,N-dichlorotoluenesulfonamide (TsNCl₂) and acetonitrile as nitrogen sources was reported. The catalytic diamination reaction was convenient to carry out, resulting in imidazoline products with good yields and excellent regio- and stereoselectivities. Several other organic molecules were also tried as catalyst for this reaction and good results were achieved. A new one-pot synthesis of vicinal diamines via the current PPh₃-catalyzed diamination and the hydrolysis of resulting imidazoline products with SnCl₄ as promoter was also established.

Full text of DOI:10.1016/j.tet.2010.04.054

Tetrahedron 66 (2010) 4555e4559
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Tetrahedron
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Organocatalyzed regio- and stereoselective diamination of functionalized alkenes
,
c
,
b,
Hui Wu a, Xiaoyun Ji a, Hao Sun a, Guanghui An a, Jianlin Han a , Guigen Li , Yi Pan
*
*
*
a School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
b State Key Laboratory of Coordination, Nanjing University, Nanjing 210093, China
c Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061, USA
a r t i c l e i n f o
a b s t r a c t
Article history:
The first organocatalyzed diamination reaction of alkenes with N,N-dichlorotoluenesulfonamide (TsNCl2)
and acetonitrile as nitrogen sources was reported. The catalytic diamination reaction was convenient to
carry out, resulting in imidazoline products with good yields and excellent regio- and stereoselectivities.
Several other organic molecules were also tried as catalyst for this reaction and good results were
achieved. A new one-pot synthesis of vicinal diamines via the current PPh3-catalyzed diamination and
the hydrolysis of resulting imidazoline products with SnCl4 as promoter was also established.
Ó 2010 Elsevier Ltd. All rights reserved.
Received 25 February 2010
Received in revised form 7 April 2010
Accepted 13 April 2010
Available online 24 April 2010
Keywords:
Diamination
Organocatalyst
Imidazoline
Triphenylphosphine
Vicinal diamines
1. Introduction
chemoselectivity, and stereoselectivity.7 So, the development of
new efficient diamination methods becomes very urgent.
The vicinal diamines represent a class of organic compound,1
which is extremely important for organic synthesis, medicinal
chemistry, and pharmaceutical research.2,3 This functionality also
exists in many biologically important compounds. The vicinal
diamines have been used as organocatalyst or chiral ligands for
asymmertric synthesis.4,5 Despite their extensive value and utility,
the approaches to this vicinal diamine functionality in regio- and
stereoselective still remain great challenges.6 In the recent years,
direct catalytic oxidative alkenes diamination presents an attractive
access for generation of vicinal diamines. These intermolecular or
intramolecular oxidative diamination systems were usually cata-
lyzed by palladium or copper with alkyl ureas7e9 or di-tert-butyl-
diaziridinone10 as nitrogen resources. Electrophilic diamination
reactions also gave an alternative methodology for the preparation
of vicinal diamines.11,12 Rhodium or iron complex was used as
catalyst for these electrophilic diamination systems, to convert
functionalized alkenes into imidazoline dimaine functionalitis.11
Although oxidative diamination and electrophilic diamination
have achieved success in the formation of vicinal diamines, there
still exist limitations in yield, product diversification, reaction rates,
Triphenylphosphine is a commercially available reagent and
tertiary phosphines are known as organocatalyst for many catalytic
organic reactions.13 In our previous reported electrophilic diami-
nation reaction, the metal complexes with triphenylphosphine were
found to be efficient catalysts for this electrophilic diamination
reaction.11b,c In our continuous work about diamiantion reaction, we
become interested in investigating whether phosphine can catalyze
the diamination reaction of alkenes. Herein, we reported our results
about the firstorganocatalyzed diamination reaction of alkeneswith
TsNCl2 and acetonitrile as nitrogen resource (Scheme 1).
CHCl2
O
Ts
N
N
PPh3
CH3CN
TsNCl2
R1
R2
R1
COR2
( )
Scheme 1. Diamination of alkenes catalyzed by PPh3.
2. Results and discussion
Initially, PPh3 was used as catalyst for the diamination of chal-
cone 1a under the previous reported diamination conditions.11b
The reaction was performed in acetonitrile catalyzed by 20 mol %
* Corresponding authors. Tel.: þ86 25 83592846; fax: þ86 25 83309123; e-mail
addresses: molab@nju.edu.cn (J. Han), guigen.li@ttu.edu (G. Li), yipan@nju.edu.cn
(Y. Pan).
0040-4020/$ e see front matter Ó 2010 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2010.04.054

4556
H. Wu et al. / Tetrahedron 66 (2010) 4555e4559
Table 2
of triphenylphosphine with TsNCl2 as nitrogen resource, and the
expected diamine product 2a was observed by 1H NMR after 24 h.
To improve the yield, the reaction conditions were optimized,
and the results were listed in Table 1. Slightly more diamine product
was obtained when increasing the loading amount of triphenyl-
phosphine from 20% to 30% (Table 1, entries 1e2). Acetonitrile
seemed to be the best choice of solvent, as the use of other cosol-
vents, such as CH2Cl2, DMF, THF, and toluene together with aceto-
nitrile, gave none or only a trace amount of the desired product
(Table 1, entries 3e6). Increase of the loading amount of TsNCl2
failed to give any improvement in chemical yield (Table 1, entry 7).
The temperature appeared to have some influence on the chemical
yields. The best yield was obtained when the reaction was per-
formed at 30 ꢀC (Table 1, entries 8e10). Similar to our previous
Results of triphenylphosphine-catalyzed diamination of alkenesa
CHCl2
Ts
O
N
N
PPh3
CH3CN
TsNCl2
R1
R2
R1
COR2
( )
2a-2l
1a-1l
Entry Substrates R1
R2
Product (ꢁ) anti/synb Yieldc (%)
1
2
3
4
5
6
1a
1b
1c
1d
1e
1f
Ph
Ph
Ph
Ph
Ph
4-ClePh
4-BrePh
2a
2b
2c
>95:1
>95:1
>95:1
>95:1
>95:1
>95:1
83
80
78
75
68
59
4-MeePh 2d
ꢀ
catalytic system that 4 A molecular sieve could promote the for-
4-Cl-Ph Ph
2-Cl-Ph Ph
2e
2f
ꢀ
mation of product, the yield decreased to 70% when no 4 A mo-
lecular sieve was used in the reaction (Table 1, entry 11). Extension
the reaction time to 48 h almost had no effect on the completion of
the reaction, but a lower yield would be obtained when the reaction
was stopped at 12 h (Table 1, entries 12e13). If no triphenylphos-
phine catalyst was used in the diamination reaction, only 57% yield
was obtained (Table 1, entry 14).
O
7
1g
2g
N/A
88
8
9
10
11
12
1h
1i
1j
1k
1l
Ph
Ph
Ph
4-F-Ph
OMe
OEt
OPh
OMe
2h
2i
2j
2k
2l
>95:1
>95:1
>95:1
>95:1
>95:1
72
70
69
71
70
4-Cl-Ph OMe
Table 1
a
Carried out at 30 ꢀC for 30 h in CH3CN with alkenes as limiting reagent (alkenes/
Diamination of chalcone 1a with TsNCl2 under various conditionsa
ꢀ
TsNCl2¼1:3) using 20 mol % PPh3 in the presence of 4 A molecular sieves.
Estimated by crude 1H NMR determination. >95% means no minor isomer was
b
CHCl2
detected.
O
Ts
c
N
N
Isolated yields.
PPh3
CH3CN
TsNCl2
Ph
Ph
Ph
COPh
The mechanism of this catalytic system is believed to be similar to
thatof our previous reported metal complexcatalyzed reactions.11 In
the initial step of the catalytic process, PPh3 is assumed to active the
nitrogen source (TsNCl2), followed by reaction with chalcone,
resulting in A. Then is the key step, which involves the formation of
N-tosyl,N-chloroaziridinium intermediate B. And this aziridinium
intermediate is next subjected to [2þ3] cycloaddition with aceto-
nitrile to form the 1N-tosyl,1N-chloroimidazolinium D. The follow-
ing steps involve SN20 and elimination reactions prior to forming the
final product 2a (Scheme 2).11
( )
2a
1a
Entry TsNCl2 (mmol) Solvent
Cat. (mol %) Time (h) T (ꢀC) Yieldb (%)
1
2
3
4
5
6
7
8
3
3
3
3
3
3
4
3
3
3
3
3
3
3
CH3CN
CH3CN
CH2Cl2
DMFc
20
30
20
20
20
30
30
30
30
30
30
30
30
30
30
30
12
48
30
30
30
30
30
30
30
30
5
25
50
30
30
30
30
80
83
c
<10
<10
<10
<10
75
THFc
Toluenec 20
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
20
20
20
20
20
20
20
0
40
77
9
Ts
PPh3
Cl
Cl
N
δ
10
11
12
13
14
76
Ts
N
70d
53
Cl
TsNCl2
PPh3
COPh
COPh
Ph
COPh
Ph
85
57
Ph
B
A
H
CH3
C
N
a
ꢀ
H
Reactions were carried out using 1 mmol 1a in 6 mL solvent with 0.5 g 4 A
H
Ts
N
Me
molecular sieves.
Cl
Cl-
b
Isolated yields.
Cl
Cl
N
c
N
N
Ts
Solvent of 5 mL and 1 mL acetonitrile was used together.
N
Ts
COPh
d
ꢀ
COPh
No 4 A molecular sieves was used.
COPh
Ph
Ph
Ph
C
E
D
Cl
Cl
Cl
Cl
Cl
N
Using the above optimized reaction condition, we next
investigated the scope and limitations of this new PPh3-based
N
N
Ts
COPh
N
N
Ts
N
Ts
COPh
Ph
COPh
Ph
Ph
G
catalytic system (Table 2). It was found that both
a
,b
-unsaturated
F
2a
ketone and -unsaturated ester work well in this system. Good
a,b
Scheme 2. Possible mechanism for the triphenylphosphine-catalyzed diamination
to excellent yield was obtained for all the substrates, even for the
substrate with strong electron-withdrawing group on the aro-
matic ring (Table 2, entry 12). Especially for aliphatic substrate,
the highest yield was obtained (88% yield) (Table 2, entry 7). The
obvious improvement on chemical yield was observed comparing
to the previous reported transition metal catalyzed diamination
system (Table 2, entries 1, 2, 7e9).11b,c Furthermore, these sub-
strates showed excellent stereoselectivities, only the anti isomers
were found. Also, only one regioisomer was detected for all these
twelve cases.
process.
After triphenylphosphine was found to be an efficient catalyst
for diamination reaction, the scope of organocatalyst for this
reaction was then explored. Base on the assumption that tri-
phenylphosphine can active NeCl bond of nitrogen source,
several regular organic compounds, which are expected to be
able to react with TsNCl2 are employed as catalysts for the
current catalytic system, and the results were shown in Table 3.
Diphenylsulfane, tributylamine, dibutylamine, and aminoalcohol

H. Wu et al. / Tetrahedron 66 (2010) 4555e4559
4557
Table 3
structural analysis (Fig. 1). This one-pot reaction provides an easy
access to the synthesis of -differentiated 1,2-vicinal diamines
Organocatalyzed electrophilic diamination of chalconea
a,b
starting from readily available and inexpensive olefins.
CHCl2
Ts
O
3. Conclusion
N
N
TsNCl2, CH3CN
Ph
Ph
In summary, triphenylphospine found to be efficient organo-
catalysts for diamination of olefins with TsNCl2 the nitrogen source,
resulting in imidazoline derivatives in high chemical yields and
excellent regio- and stereoselectives. The reaction provides an easy
organocatalyst
Ph
COPh
( )
2a
1a
Entry Catalyst
Amount (mmol%) Time (h) anti/synb Yieldc (%)
way to synthesize the
a,b-differentiated 1,2-vicinal diamines. In
1
2
3
4
Diphenylsulfane 20
30
30
30
30
>95:1
>95:1
>95:1
>95:1
79
61
65
77
addition, various regular organic compounds can also be used as
catalyst for this reaction. A new one-pot synthesis of vicinal
diamines via the current PPh3-catalyzed diamination and the
hydrolysis of resulting imidazoline products with SnCl4 as promoter
was also established.
Bu3N
Bu2NH
20
20
2-Aminoethanol 20
a
Carried out at 30 ꢀC in CH3CN with alkenes as limiting reagent (alkenes/
ꢀ
TsNCl2¼1:3) in the presence of 4 A molecular sieves.
b
Regio- and stereoselectivity >95:1 for all these reactions, and estimated by
crude 1H NMR.
4. Experimental section
4.1. General
c
Isolated yields.
were tried, and all of these compounds can efficiently catalyze
the diamination reaction to give desired diamine products in
good yields, high regio- and stereoselectivities.
Finally, a new one-pot reaction condition for the highly stereo-
selective synthesis of a,b-differentiated 1,2-vicinal diamines was also
established, which contains the current triphenylphosphine-catalyzed
diamination reaction and the hydrolysis of the resulting imidazoline
productswithSnCl4 aspromoter(Table 4).11e,14 AsshowninTable 4, the
highly stereoselecitive one-pot reaction was convenient to carry out,
and moderate to good chemical yields were obtained. The stereo-
chemistry of this reaction was unambiguously confirmed by X-ray
Melting points were uncorrected. IR spectra were collected on
Bruker Vector 22 in KBr pellets. 1H NMR, 13C NMR (TMS used as
internal standard) spectra were recorded on Bruker ARX-300
spectrometer. Elemental analyses were performed on a Per-
kineElmer 240 elemental analysis instrument. Mass spectrum was
done by Finnigan TSQ7000 Electrospray Mass Spectrometer. Thin
layer chromatography was carried out on Silica Gel 60 F-254 TLC
plates. 20ꢂ20 cm Gel 60 F-254 TLC plates were used for Isolation.
4.2. General procedure for electrophilic diamination
Table 4
One-pot synthesis of
a
,b
-differentiated 1,2-vicinal diamines
Into
0.2 mmol), 4 A molecular sieves (0.5 g), and freshly distilled ace-
tonitrile (6 mL). Then -unsaturated ketone or carboxylic ester
a dry vial was added triphenylphosphine (5.2 mg,
CHCl2
NH
ꢀ
1) TsNCl2, CH3CN
a,b
O
O
PPh3, rt, 30 h
(1 mmol) was added to the stirred mixture. TsNCl2 (0.72 g, 3 mmol)
was added as solid for 5 min, shortly after TsNCl2 was added. The
resulting slurry was stirred at 30 ꢀC for 30 h in the capped vial
COR2
R1
R2
R1
2) SnCl4, H2O, 1 h, rt
NHTs
ꢀ
without argon protection. The 4 A molecular sieves and other solid
(+/-)
precipitates were filtered off and washed with EtOAc (3ꢂ15 mL).
The organic solution was directly concentrated without quenching
and then purified via TLC plate (petroleum ether/EtOAc¼5:1) to
give 1-p-toluenesulfonyl-2-dichloromethyl-imidazoline 2ael.
Entry
Substrates
R1
R2
Producta (ꢁ)
3a
3c
3h
3k
Yieldb (%)
1
2
3
4
1a
1c
1h
1k
Ph
Ph
Ph
4-FePh
Ph
74
60
51
45
4-BrePh
OMe
OMe
4.2.1. Compound 2a. Compound 2a was isolated as white solid. Mp
a
144e145 ꢀC. 1H NMR (300 MHz, CDCl3)
d 7.67e7.81 (m, 4H),
Regio- and stereoselectivity >95:1 for all these reactions, and estimated by
crude 1H NMR.
7.62e7.67 (m, 1H), 7.45e7.50 (m, 2H), 7.25e7.33 (m, 6H), 6.90 (d,
J¼6.77 Hz, 2H), 5.57 (d, J¼4.87 Hz, 1H), 5.02 (d, J¼4.79 Hz, 1H), 2.46
b
Isolated yields.
(s, 3H); 13C NMR (75 MHz, CDCl3)
d 193.7, 157.1, 146.1, 139.0, 134.7,
134.7, 133.8, 130.5, 129.5, 129.4, 129.2, 129.1, 128.3, 126.9, 72.6, 72.2,
61.8, 22.0; IR (KBr): 1691; MS (ESI): calcd for [C24H20Cl2N2O3S]
([MþH]þ): 487.06, found: 487.00. Anal. Calcd for C24H20Cl2N2O3S: C
59.14, H 4.14, N 5.75 Found: C 59.28, H 4.08, N 5.86.
4.2.2. Compound 2b. Compound 2b isolated as white solid. Mp
124e125 ꢀC.1H NMR (300 MHz, CDCl3)
d
7.80 (d, J¼8.32 Hz, 2H), 7.69
(d, J¼8.57 Hz, 2H), 7.44 (d, J¼8.53 Hz, 2H), 7.22e7.34 (m, 6H), 6.90 (d,
J¼6.76 Hz, 2H), 5.49 (d, J¼5.11 Hz, 1H), 5.02 (d, J¼5.07 Hz, 1H), 2.47
(s, 3H); 13C NMR (75 MHz, CDCl3)
d 192.7, 157.1, 146.2, 141.4, 138.9,
134.6, 132.1, 130.5, 129.7, 129.5, 129.3, 129.2, 128.3, 126.9, 72.7, 72.3,
61.7, 22.1; IR (KBr): 1698; MS (ESI): calcd for [C24H19Cl3N2O3S]
([MþH]þ): 521.02, found: 520.95. Anal. Calcd for C24H19Cl3N2O3S: C
55.24, H 3.67, N 5.37. Found: C 55.25, H 3.52, N 5.25.
4.2.3. Compound 2c. Compound 2c was isolated as white solid. Mp
132e133 ꢀC. 1H NMR (300 MHz, CDCl3)
d
7.77 (d, J¼8.29 Hz, 2H),
Figure 1. ORTEP diagram showing 3c.

4558
H. Wu et al. / Tetrahedron 66 (2010) 4555e4559
7.62 (s, 4H), 7.22e7.34 (m, 6H), 6.89 (d, J¼6.87 Hz, 2H), 5.49 (d,
J¼5.10 Hz, 1H), 5.02 (d, J¼5.05 Hz, 1H), 2.47 (s, 3H); 13C NMR
([MþH]þ): 455.05, found: 454.97. Anal. Calcd for C20H20Cl2N2O4S: C
52.75, H 4.43, N 6.15. Found: C 52.84, H 4.32, N 6.02.
(75 MHz, CDCl3) d 192.9, 157.1,146.3, 138.9, 134.6, 132.7,132.5, 130.6,
130.5, 130.2, 129.5, 129.2, 128.3, 126.9, 72.6, 72.3, 61.7, 22.1; IR (KBr):
1700; MS (ESI): calcd for [C24H19BrCl2N2O3S] ([MþH]þ): 564.97,
found: 564.93. Anal. Calcd for C24H19BrCl2N2O3S: C 50.90, H 3.38, N
4.95. Found: C 50.83, H 3.30, N 5.05.
4.2.10. Compound 2j. Compound 2j was isolated as white solid. Mp
118e119 ꢀC. 1H NMR (300 MHz, CDCl3)
d
7.78 (d, J¼8.34 Hz, 2H),
7.40e7.42 (m, 2H), 7.24e7.31 (m, 7H), 7.14 (dd, J¼1.14, 8.68 Hz, 2H),
6.99 (dd, J¼1.67, 7.76 Hz, 2H), 5.42 (d, J¼4.48 Hz, 1H), 4.79 (d,
J¼4.55 Hz, 1H), 2.43 (s, 3H); 13C NMR (75 MHz, CDCl3)
d 168.3, 157.1,
4.2.4. Compound 2d. Compound 2d was isolated as white solid.
150.5, 146.3, 139.4, 134.2, 130.6, 129.9, 129.3, 128.7, 128.2, 126.9,
126.3, 121.4, 72.7, 69.7, 61.8, 22.0; IR (KBr): 1759; MS (ESI): calcd for
[C24H20Cl2N2O4S] ([MþH]þ): 503.05, found: 502.99. Anal. Calcd for
C24H20Cl2N2O4S: C 57.26, H 4.00, N 5.56. Found: C 57.12, H 4.05, N
5.48.
Mp 159e161 ꢀC. 1H NMR (300 MHz, CDCl3)
d
7.78 (d, J¼8.37 Hz,
2H), 7.66 (d, J¼8.15 Hz, 2H), 7.24e7.34 (m, 8H), 6.91 (d, J¼6.81 Hz,
2H), 5.55 (d, J¼4.84 Hz, 1H), 5.02 (d, J¼4.78 Hz, 1H), 2.46 (s, 3H),
2.45 (s, 3H); 13C NMR (75 MHz, CDCl3)
d 193.1, 157.1, 146.1, 145.9,
139.1, 134.8, 131.2, 130.5, 130.1, 129.4, 129.3, 129.0, 128.3, 127.0,
72.7, 72.1, 61.8, 22.2, 22.1; IR (KBr): 1697; MS (ESI): calcd for
[C25H22Cl2N2O3S] ([MþH]þ): 501.07, found: 501.02. Anal. Calcd for
C25H22Cl2N2O3S: C 59.88, H 4.42, N 5.59. Found: C 59.83, H 4.56, N
5.61.
4.2.11. Compound 2k. Compound 2k was isolated as white solid.
Mp 123e124 ꢀC. 1H NMR (300 MHz, CDCl3)
d
7.69 (d, J¼8.32 Hz, 2H),
7.25 (d, J¼8.08 Hz, 2H), 7.20 (s, 1H), 6.88 (d, J¼6.88 Hz, 4H), 5.22 (d,
J¼4.23 Hz, 1H), 4.52 (d, J¼4.28 Hz, 1H), 3.82 (s, 3H), 2.44 (s, 3H); 13C
NMR (75 MHz, CDCl3) d 170.0, 164.4, 161.1, 157.4, 146.3, 135.6, 134.1,
4.2.5. Compound 2e. Compound 2e was isolated as white solid. Mp
130.5, 128.0, 127.9, 116.2, 115.9, 71.6, 69.5, 61.7, 53.5, 21.9; IR (KBr):
1762; MS (ESI): calcd for [C19H17Cl2FN2O4S] ([MþH]þ): 459.03,
found: 458.93. Anal. Calcd for C19H17Cl2FN2O4S: C 49.68, H 3.73, N
6.10. Found: C 49.66, H 3.74, N 6.29.
124e125 ꢀC. 1H NMR (300 MHz, CDCl3)
d 7.74e7.78 (m, 4H),
7.64e7.68 (m, 1H), 7.46e7.51 (m, 2H), 7.23e7.32 (m, 5H), 6.84 (d,
J¼8.41 Hz, 2H), 5.50 (d, J¼4.87 Hz, 1H), 5.02 (d, J¼4.85 Hz, 1H), 2.46
(s, 3H); 13C NMR (75 MHz, CDCl3)
d 193.5, 157.6, 146.3, 137.7, 135.0,
134.8, 134.6, 133.8, 130.5, 129.6, 129.4, 129.1, 128.2, 72.0, 71.9, 61.7,
22.0; IR (KBr): 1693; MS (ESI): calcd for [C24H19Cl3N2O3S]
([MþH]þ): 521.02, found: 520.96. Anal. Calcd for C24H19Cl3N2O3S: C
55.24, H 3.67, N 5.37. Found: C 55.28, H 3.66, N 5.25.
4.2.12. Compound 2l. Compound 2l was isolated as white solid. Mp
105e106 ꢀC. 1H NMR (300 MHz, CDCl3)
d
7.65 (d, J¼8.37 Hz, 2H),
7.14e7.27 (m, 5H), 6.83 (d, J¼8.33 Hz, 2H), 5.20 (d, J¼4.07 Hz, 1H),
4.50 (d, J¼4.16 Hz, 1H), 3.82 (s, 3H), 2.44 (s, 3H); 13C NMR (75 MHz,
CDCl3)
d 169.9, 157.6, 146.4, 138.3, 134.4, 134.0, 130.4, 129.3, 127.9,
4.2.6. Compound 2f. Compound 2f was isolated as white solid. 1H
127.5, 71.5, 69.5, 61.7, 53.6, 22.0; IR (KBr): 1759; MS (ESI): calcd for
[C19H17Cl3N2O4S] ([MþH]þ): 475.00, found: 474.99. Anal. Calcd for
C19H17Cl3N2O4S: C 47.96, H 3.60, N 5.89. Found: C 47.92, H 3.63, N
5.92.
NMR (300 MHz, CDCl3)
d
7.80 (d, J¼7.46 Hz, 2H), 7.71 (d, J¼7.46 Hz,
2H), 7.60e7.65 (m, 1H), 7.43e7.48 (m, 2H), 7.23e7.28 (m, 5H),
7.13e7.17 (m, 1H), 6.84 (d, J¼7.53 Hz, 1H), 5.61 (d, J¼5.18 Hz, 1H),
5.53 (d, J¼5.18 Hz, 1H), 2.42 (s, 3H); 13C NMR (75 MHz, CDCl3)
d
194.8, 157.9, 146.1, 136.9, 134.5, 132.7, 130.4, 130.1, 130.0, 129.2,
4.3. General procedure for the one-pot synthesis of vicinal
diamines
129.1, 128.7, 128.2, 127.8, 69.9, 69.6, 61.8, 22.0; IR (KBr): 1684; MS
(ESI): calcd for [C24H19Cl3N2O3S] ([MþH]þ): 521.02, found: 520.96.
Anal. Calcd for C24H19Cl3N2O3S: C 55.24, H 3.67, N 5.37. Found: C
55.31, H 3.50, N 5.47.
Into
0.2 mmol), 4 A molecular sieves (0.5 g) and freshly distilled aceto-
nitrile (6 mL). Then -unsaturated ketone or carboxylic ester
a dry vial was added triphenylphosphine (5.2 mg,
ꢀ
a,b
4.2.7. Compound 2g. Compound 2g was isolated as white solid. Mp
(1 mmol) was added to the stirred mixture. TsNCl2 (0.72 g, 3 mmol)
was added as solid for 5 min, shortly after TsNCl2 was added. The
resulting slurry was stirred at room temperature for 30 h in the
capped vial without argon protection. Then, H2O (5.0 mL) and
SnCl4$5H2O (1.75 g, 5.0 mmol) were added with strong stirring.
95e97 ꢀC. 1H NMR (300 MHz, CDCl3)
d
7.74 (d, J¼8.25 Hz, 2H), 7.40
(d, J¼8.04 Hz, 2H), 7.21 (s, 1H), 4.00 (s, 1H), 2.48 (s, 3H), 2.23 (s, 3H),
1.22 (s, 3H), 0.90 (s, 3H); 13C NMR (75 MHz, CDCl3)
206.0, 153.9,
d
146.5, 133.5, 130.8, 128.0, 76.9, 70.8, 62.1, 31.1, 28.2, 23.6, 22.1; IR
(KBr): 1718; MS (ESI): calcd for [C15H18Cl2N2O3S] ([MþH]þ): 377.04,
found: 376.96. Anal. Calcd for C15H18Cl2N2O3S: C 47.75, H 4.81, N
7.42. Found: C 47.60, H 4.92, N 7.31.
ꢀ
After 1 h, the 4 A molecular sieves and other solid precipitates were
filtered off and washed with EtOAc (10 mL). The aqueous layer was
extracted with EtOAc (3ꢂ30 mL), and the combined organic solu-
tion was concentrated and then purified via TLC plate (petroleum
ether/EtOAc¼2.5:1) to give products 3.
4.2.8. Compound 2h. Compound 2h was isolated as white solid. Mp
125e126 ꢀC. 1H NMR (300 MHz, CDCl3)
d
7.69 (d, J¼8.28 Hz, 2H),
7.18e7.27 (m, 6H), 6.89 (d, J¼7.19 Hz, 2H), 5.22 (d, J¼4.31 Hz, 1H),
4.3.1. Compound 3a. Compound 3a was isolated as white solid. Mp
4.57 (d, J¼4.38 Hz, 1H), 3.82 (s, 3H), 2.43 (s, 3H); 13C NMR (75 MHz,
157e159 ꢀC. 1H NMR (300 MHz, CDCl3)
d 7.50e7.58 (m, 5H),
CDCl3)
d
170.1, 157.0, 146.1, 139.6, 134.1, 130.5, 129.1, 128.4, 128.0,
7.25e7.36 (m, 8H), 7.04 (d, J¼8.00 Hz, 2H), 6.03 (d, J¼8.93 Hz, 1H),
126.2, 72.4, 69.5, 61.8, 53.5, 22.0; IR (KBr): 1758; MS (ESI): calcd for
[C19H18Cl2N2O4S] ([MþH]þ): 441.04, found: 440.97. Anal. Calcd for
C19H18Cl2N2O4S: C 51.71, H 4.11, N 6.35. Found: C 51.57, H 4.08, N
6.42.
5.91 (s, 1H), 5.20e5.31 (m, 2H), 2.25 (s, 3H); 13C NMR (75 MHz,
CDCl3)
d 196.5, 164.3, 144.3, 136.6, 136.5, 134.7, 134.5, 130.0, 129.4,
129.0, 128.6, 127.4, 127.3, 66.5, 60.7, 56.1, 21.7; IR (KBr) 3367, 3269,
3064, 1677, 1342, 1165; MS (ESMS/[MþH]þ) calcd for
C24H22Cl2N2O4SH: 505.1, found: 504.8. C24H22Cl2N2O4S: calcd C
57.03, H 4.39, N 5.54, found C 57.23, H 4.33, N 5.45.
4.2.9. Compound 2i. Compound 2i was isolated as white solid. Mp
99e101 ꢀC. 1H NMR (300 MHz, CDCl3)
d
7.70 (d, J¼8.33 Hz, 2H),
7.18e7.27 (m, 6H), 6.90 (d, J¼6.47 Hz, 2H), 5.22 (d, J¼4.24 Hz, 1H),
4.3.2. Compound 3c. Compound 3c was isolated as white solid. Mp
4.57 (d, J¼4.31 Hz, 1H), 4.25 (q, J¼7.13 Hz, 2H), 2.43 (s, 3H), 1.31 (t,
144e146 ꢀC. 1H NMR (300 MHz, CDCl3)
d
7.55 (d, J¼8.00 Hz, 2H),
J¼7.13 Hz, 3H); 13C NMR (75 MHz, CDCl3)
d
169.6, 157.0, 146.1, 139.6,
7.44 (d, J¼8.36 Hz, 2H), 7.28e7.36 (m, 8H), 7.06 (d, J¼7.87 Hz, 2H),
134.3, 130.4, 129.2, 128.4, 128.0, 126.2, 72.5, 69.6, 62.7, 61.8, 22.0,
14.4; IR (KBr): 1751; MS (ESI): calcd for [C20H20Cl2N2O4S]
6.01 (d, J¼9.16 Hz, 1H), 5.92 (s, 1H), 5.24e5.29 (m, 1H), 5.12e5.15
(m, 1H), 2.28 (s, 3H); 13C NMR (75 MHz, CDCl3)
d 195.8, 164.5, 144.5,

H. Wu et al. / Tetrahedron 66 (2010) 4555e4559
2. (a) Ojima, I. In The Organic Chemistry of
4559
b
-Lactams; Georg, G. I., Ed.; VCH:
136.5, 136.4, 133.5, 132.3, 130.0, 130.0, 129.8, 129.4, 129.1, 127.4,
127.4, 66.5, 60.6, 56.0, 21.8; IR (KBr): 3313, 3267, 3032, 1680, 1343,
1072; MS (ESMS/[MþH]þ) calcd for C24H21BrCl2N2O4SH: 582.9,
found: 583.0. C24H21BrCl2N2O4S: calcd C 49.33, H 3.62, N 4.79,
New York, NY, 1992; pp 197e255; (b) Ojima, I. Acc. Chem. Res. 1995, 28,
383e389.
3. (a) Thierry Le Gall, D. L.; Mioskowski, C. Angew. Chem., Int. Ed. 1998, 37,
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63, 2045e2047.
6. (a) Becker, P. N.; White, M. A.; Bergman, R. G. J. Am. Chem. Soc. 1980, 102,
5676e5677; (b) Becker, P. N.; Bergman, R. G. Organometallics 1983, 2, 787e796;
(c) Ghomi, S.; Orr, D. E. Chem. Ind. 1983, 928; (d) Fristad, W. E.; Brandvold, T. A.;
Peterson, J. R.; Thompson, S. R. J. Org. Chem. 1985, 50, 3647e3649; (e) Muñiz, K.;
Iesato, A.; Nieger, M. Chem.dEur. J. 2003, 9, 5581e5596; (f) Booker-Milburn, K.
I.; Guly, D. J.; Cox, B.; Procopiou, P. A. Org. Lett. 2003, 5, 3313e3315.
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found
C 49.19, H 3.42, N 4.92; crystal data for 3c: 3
(C24H21BrCl2N2O4S), H2O; formula weight, 1770.91; monoclinic,
ꢀ
space group P2(1)/c; a¼20.8165(19), b¼17.2483(16), c¼21.723(2) A;
3
ꢀ
b
¼97.026(2); V¼7741.1(12) A ; Z¼4; Dcalcd¼1.520 g cmꢃ3; F(000)¼
3592; crystal size¼0.32ꢂ0.26ꢂ0.24 mm; 2qmax¼52.0ꢀ; reflections
collected,15,171; reflections used, 10,507; R1¼0.0586; wR2¼0.1181;
GOF¼1.02. CCDC number, 627034.
4.3.3. Compound 3h. Compound 3h was isolated as white solid. Mp
168e170 ꢀC. 1H NMR (300 MHz, CDCl3)
d
7.65 (d, J¼8.22 Hz, 2H),
7.46 (d, J¼8.07 Hz, 1H), 7.24e7.35 (m, 7H), 5.92 (s, 1H), 5.42 (d,
J¼9.33 Hz, 1H), 5.27e5.32 (m, 1H), 4.34e4.39 (m, 1H), 3.49 (s, 3H),
2.42 (s, 3H); 13C NMR (75 MHz, CDCl3)
d 169.7, 164.2, 144.4, 136.6,
135.9, 130.1, 129.3, 129.1, 127.5, 127.2, 66.5, 59.7, 55.9, 53.3, 21.9; IR
(KBr): 3320, 3264, 3066,1744,1672,1345,1162; MS (ESMS/[MþH]þ)
calcd for C19H20Cl2N2O5SH: 459.0, found: 458.8. C19H20Cl2N2O5S:
calcd C 49.68, H 4.39, N 6.10, found C 49.60, H 4.52, N 6.31.
8. (a) Bar, G. L. J.; Lloyd-Jones, G. C.; Booker-Milburn, K. I. J. Am. Chem. Soc. 2005,
€
127, 7308e7309; (b) Streuff, J.; Hovelmann, C. H.; Nieger, M.; Muñiz, K. J. Am.
€
Chem. Soc. 2005, 127, 14586e14587; (c) Muñiz, K.; Hovelmann, C. H.; Streuff, J.
J. Am. Chem. Soc. 2008, 130, 763e773; (d) Brice, J. L.; Harang, J. E.; Timokhin, V. I.;
Anastasi, N. R.; Stahl, S. S. J. Am. Chem. Soc. 2005, 127, 2868e2869; (e) Muñiz, K.;
4.3.4. Compound 3k. Compound 3k was isolated as white solid. Mp
172e174 ꢀC. 1H NMR (300 MHz, CDCl3)
d
7.64 (d, J¼8.26 Hz, 2H),
€
Streuff, J.; Hovelmann, C. H.; Núñez, A. Angew. Chem. 2007, 119, 7255e7258; (f)
€
Muñiz, K.; Hovelmann, C. H.; Campos-Gómez, E.; Barluenga, J.; González, J. M.;
7.44 (d, J¼8.25 Hz, 1H), 7.22e7.29 (m, 4H), 6.99e7.05 (m, 2H), 5.93
Streuff, J.; Nieger, M. Chem.dAsian J. 2008, 3, 776e788; (g) Muñiz, K.; Streuff, J.;
€
(s, 1H), 5.46e5.49 (m, 1H), 5.28e5.33 (m, 1H), 4.29e4.34 (m, 1H),
Chávez, P.; Hovelmann, C. H. Chem.dAsian J. 2008, 3, 1248e1255; (h) Muñiz, K.
3.51 (s, 3H), 2.43 (s, 3H); 13C NMR (75 MHz, DMSO-d6)
d 169.9,
€
J. Am. Chem. Soc. 2007, 129, 14542e14543; (i) Hovelmann, C. H.; Streuff, J.;
Brelot, L.; Muñiz, K. Chem. Commun. 2008, 2334e2336.
164.2, 160.8, 143.4, 138.4, 134.1, 130.1, 129.8, 129.6, 127.1, 116.0, 115.7,
67.6, 60.6, 54.7, 52.8, 21.7; IR (KBr) 3325, 3203, 1745, 1655, 1345,
1145; MS (ESMS/[MþNa]þ) calcd for C19H19Cl2FN2O5SNa: 499.0,
found: 498.8. C19H19Cl2FN2O5S: calcd C 47.81, H 4.01, N 5.87, found C
47.76, H 4.12, N 5.68.
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Acknowledgements
The research funds for Y. Pan from Kua-Shi-Ji program of Edu-
cation Ministry of China, National Natural Science Foundation of
China (Grant No. 20772056 and 20932004) and Jiangsu 333 pro-
gram (for Pan) are acknowledged.
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Supplementary data
12. (a) Brooker-Milburn, K. I.; Guly, D. J.; Cox, B.; Procopiou, P. A. Org. Lett. 2003, 5,
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Supplementary data associated with this article can be found in
online version at doi:10.1016/j.tet.2010.04.054. These data include
MOL files and InChIKeys of the most important compounds de-
scribed in this article.
References and notes
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