Sc(OTf)3-Catalysed ring-opening of aziridines with phenol derivatives under solvent-free conditions

Article abstract of DOI:10.3184/030823408X320610

Scandium(III) triflate-catalysed ring opening of aziridines with phenol derivatives affords various 2-amino ethers 3 (eg 4-methyl-N-(2-phenoxy-2- phenylethyl) benzenesulfonamide) with high regioselectivity and high yields under solvent-free conditions. Th

Full text of DOI:10.3184/030823408X320610

JOURNAL OF CHEMICAL RESEARCH 2008
MAY, 297–300
RESEARCH PAPER 297
Sc(OTf)3-Catalysed ring-opening of aziridines with phenol derivatives
under solvent-free conditions
Ren’er Chen, Ting Xie, Can Jin and Weike Su*
Key Laboratory of Pharmaceutical Engineering (Zhejiang University of Technology), Ministry of Education,
College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, P.R. China
Scandium(III) triflate-catalysed ring opening of aziridines with phenol derivatives affords various 2-amino ethers 3
(eg 4-methyl-N-(2-phenoxy-2-phenylethyl) benzenesulfonamide) with high regioselectivity and high yields under
solvent-free conditions. The unexpectedly rearranged product 4 (e.g. 4-methyl-N-(3-methyl-3-phenoxy butyl)
benzene sulfonamide) was obtained when 2-isopropyl-N-tosylaziridine was the substrate.
Keywords: VFDQGLXPꢀ,,,ꢁꢂWULÀDWHꢃꢂULQJꢂRSHQLQJꢃꢂD]LULGLQHVꢃꢂꢄꢅDPLQRꢂHWKHUVꢃꢂUHJLRVHOHFWLYLW\ꢃꢂVROYHQWꢅIUHH
Aziridines and epoxides are valuable building blocks in ring-
opening reactions.1-5ꢂ5HFHQWO\ꢃꢂZHꢂKDYHꢂUHSRUWHGꢂWKHꢂWKLRO\VLVꢂ
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to afford EꢅK\GUR[\ꢂVXO¿GHVꢂZLWKꢂKLJKꢂUHJLRVHOHFWLYLW\ꢂXQGHUꢂ
solvent-free conditions.7 Aziridines are nitrogen analogues
of epoxides and their corresponding ring-opening products
DUHꢂ YDOXDEOHꢂ LQWHUPHGLDWHVꢂ LQꢂ RUJDQLFꢂ V\QWKHVLVꢃ8-12 but
trisubstituted and tetrasubstituted aziridines exhibit diminished
UHDFWLYLW\ꢂ GXHꢂ WRꢂ LQFUHDVHGꢂ VWHULFꢂ KLQGUDQFHꢆꢂ 5LQJꢅRSHQLQJꢂ
RIꢂ D]LULGLQHVꢂ LVꢂ SULPDU\ꢂ DQGꢂ VHFRQGDU\ꢂ DOFRKROVꢂ LVꢂ IDFLOHꢃꢂ
TsHN
Ph
Ts
N
HO
+
Ph
O
3a
2a
1a
Scheme 1
Sc(OTf )3
TsHN
R1
Ts
(1 mol%)
N
+
HO Ar
Ar
13
FDWDO\VHGꢂE\ꢂ%)3·OEt2,13 Sn(OTf)2 or H3PMo12O40/SiO2,14
Solvent-free
50oC
R1
O
EXWꢂKLQGHUHGꢂDOFRKROVꢂDQGꢂSKHQROVꢂDIIRUGꢂSRRUꢂ\LHOGVꢂXQGHUꢂ
similar conditions.13 So far, ring opening reaction of aziridines
ZLWKꢂSKHQROVꢂKDYHꢂEHHQꢂLQYHVWLJDWHGꢃꢂSURPRWHGꢂE\ꢂn-Bu3P in
toluene15 or H2O,16ꢂRUꢂFDWDO\VHGꢂE\ꢂ&X2$Fꢇ'%8ꢆ17 The main
GLVDGYDQWDJHVꢂRIꢂWKHVHꢂPHWKRGVꢂDUHꢂSRRUꢂVWHUHRVHOHFWLYLW\15,16
RUꢂORZꢂ\LHOGVꢆ17ꢂ$VꢂZDWHUꢂWROHUDQWꢃꢂUHF\FODEOHꢂFDWDO\VWVꢃꢂUDUHꢂ
HDUWKꢂPHWDOꢂWULÀDWHVꢂKDYHꢂHI¿FLHQWO\ꢂSURPRWHGꢂVHYHUDOꢂFDUERQ±
carbon or carbon–heteroatom bond forming reactions.18-20
+HUHꢂZHꢂGHVFULEHꢂDꢂVLPSOHꢂDQGꢂSUDFWLFDOꢂPHWKRGꢂIRUꢂWKHꢂULQJꢂ
RSHQLQJꢂFDWDO\VHGꢂE\ꢂ6Fꢀ27Iꢁ3.
1
2
3
Scheme 2
ZLWKꢂKLJKꢂUHJLRVHOHFWLYLW\ꢆꢂ7KHꢂVWUXFWXUHꢂRIꢂ3ꢂZDVꢂFRQ¿UPHGꢂ
E\ꢂ 1H NMR, 13&ꢂ 105ꢃꢂ 06ꢂ DQGꢂ ,5ꢆꢂ (QFRXUDJHGꢂ E\ꢂ WKLVꢂ
H[FHOOHQWꢂUHVXOWꢃꢂZHꢂH[SORUHGꢂWKHꢂVFRSHꢂRIꢂWKHꢂUHDFWLRQꢂZLWKꢂ
various aziridines 1 and phenols 2 (Scheme 2) and the results
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ZLWKꢂ HOHFWURQꢅGRQDWLQJꢂ JURXSVꢂ UHDFWHGꢂ ZLWKꢂ D]LULGLQHVꢂ WRꢂ
DIIRUGꢂ WKHꢂ FRUUHVSRQGLQJꢂ SURGXFWVꢂ ZLWKꢂ JRRGꢂ \LHOGVꢃꢂ ZKLOHꢂ
WKRVHꢂZLWKꢂHOHFWURQꢅZLWKGUDZLQJꢂJURXSVꢂJDYHꢂUHODWLYHO\ꢂORZꢂ
\LHOGVꢂ ꢀHQWULHVꢂ ꢈ±ꢈꢈꢁꢆꢂ ,Qꢂ WKHꢂ FDVHꢂ RIꢂ ꢄꢅDFHWRSKHQROꢂ ꢀ2g), no
product 3ꢂ ZDVꢂ GHWHFWHGꢂ XQGHUꢂ VLPLODUꢂ FRQGLWLRQVꢂ GXHꢂ WRꢂ WKHꢂ
LQWUDPROHFXODUꢂ K\GURJHQꢂ ERQGLQJꢆꢂ $FFRUGLQJꢂ WRꢂ SUHYLRXVꢂ
literature,21 the full mechanistic scheme for the ring opening
of 2-substituted-NꢅWRV\OD]LULGLQHꢂ1ꢂZLWKꢂSKHQROVꢂvia an SN2-
OLNHꢂSDWKZD\ꢂLVꢂJLYHQꢂE\ꢂ6FKHPHꢂꢌꢆ
,QLWLDOO\ꢃꢂWKHꢂRSHQLQJꢂUHDFWLRQꢂRIꢂꢄꢅSKHQ\Oꢅ1ꢅWRV\OD]LULGLQHꢂ
1aꢂ ZLWKꢂ SKHQROꢂ 2aꢂ ZDVꢂ FDUULHGꢂ RXW in the presence of
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Zn(OTf)2, Yb(OTf)3, and Y(OTf)3ꢃꢂ ZHUHꢂ XVHGꢃꢂ EXWꢂ YHU\ꢂ
SRRUꢂ \LHOGVꢂ ZHUHꢂ REWDLQHGꢂ ꢀ7DEOHꢂ ꢈꢁꢆꢂ )RUWXQDWHO\ꢃꢂ FDWDO\VHGꢂ
E\ꢂ 6Fꢀ27Iꢁ3ꢃꢂ WKHꢂ UHDFWLRQꢂ SURFHHGHGꢂ VPRRWKO\ꢂ LQꢂ GLIIHUHQWꢂ
solvents such as CH3NO2 (6 h, 50%), THF (6 h, 70%), CH2Cl2
(2 h, 83%). Moreover, in the case of solvent-free conditions,
the product 3a could be obtained ZLWKꢂKLJKꢂUHJLRVHOHFWLYLW\ꢂ
in ꢉꢊꢋꢂ \LHOGꢂ ZKHQꢂ ꢈꢂ PROꢋꢂ 6Fꢀ27Iꢁ3 ZDVꢂ XVHGꢂ ꢀ7DEOHꢂ ꢈꢃꢂ
(QWU\ꢂꢉꢁꢆ
7RꢂRXUꢂVXUSULVHꢃꢂZKHQꢂꢄꢅLVRSURS\OꢅNꢅWRV\OD]LULGLQH 1dꢂZDVꢂ
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PDLQꢂ SURGXFWꢂ ZDVꢂ 4 instead of 3 ꢀ6FKHPHꢂ ꢎꢁꢆꢂ7KLVꢂ PD\ꢂ EHꢂ
,WꢂZDVꢂIRXQGꢂWKDWꢂSKHQROꢂ2a attacks at the more substituted
FDUERQꢂRIꢂWKHꢂD]LULGLQHꢃꢂZKLFKꢂDIIRUGVꢂWKHꢂGHVLUHGꢂSURGXFWꢂ3a
Table 1 The ring-opening of 1a with 2a under different conditions
Entry
Catalyst
Loading/mol%
Solvent
Temperature/°C
Time/h
Yield/%a
1
2
3
4
5
6
7
8
9
AlCl3
100
10
10
10
1
CH2Cl2
CH2Cl2
CH2Cl2
CH2Cl2
CH3NO2
THF
CH2Cl2
CH2Cl2
Solvent-free
Reflux
Reflux
Reflux
Reflux
25/50/reflux
25/50/reflux
25
12
12
12
12
6
ND
Zn(OTf)2
Yb(OTf)3
Y(OTf)3
Sc(OTf)3
Sc(OTf)3
Sc(OTf)3
Sc(OTf)3
Sc(OTf)3
10
30
35
ND/52/55b
ND/70/72b
ND
1
6
1
6
1
Reflux
50
2
83b
95
1
1
ND, not determined
aIsolated yields based on 1a.
bIsolated yields based on different temperature.
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298 JOURNAL OF CHEMICAL RESEARCH 2008
Table 2 The ring-opening reaction of aziridines 1 with phenol derivatives 2 in the presence of Sc(OTf)3
Entry
R1
Ar
Product
Time/h
Yield of 3/%a
1
2
Ph (1a)
C6H5 (2a)
3a
3b
3c
3d
3e
3f
3g
3h
3i
1
1
2
2
1
1
2
2
1
1
2
4
95
94
85
82
94
93
81
78
82
78
75
0
Ph (1a)
m-CH3C6H4 (2b)
p-ClC6H4 (2c)
p-NO2C6H4 (2d)
C6H5 (2a)
3
Ph (1a)
Ph (1a)
4
5
CH3 (1b)
CH3 (1b)
CH3 (1b)
CH3 (1b)
PhCH2 (1c)
PhCH2 (1c)
PhCH2 (1c)
Ph (1a)
6
m-CH3C6H4 (2b)
p-ClC6H4 (2c)
p-NO2C6H4 (2d)
C6H5 (2a)
m-CH3C6H4 (2b)
p-ClC6H4 (2c)
o-CH3COC6H4 (2g)
7
8
9
10
11
12
3j
3k
ꢀ
aIsolated yields based on 1, the regioselectivity was determined by NMR.
General procedure
T
Ts
N
Sc(OTf)3
OAr
7Rꢂ Dꢂ PL[WXUHꢂ RIꢂ ꢄꢅSKHQ\OꢅꢈꢅWRV\OD]LULGLQHꢂ 1a (1 mmol, 0.27 g)
and phenol 2aꢂꢀꢈꢆꢑꢊꢂPPROꢃꢂꢑꢆꢈꢑꢂJꢁꢃꢂVFDQGLXPꢂWULÀDWHꢂꢀꢑꢆꢑꢈꢂPPROꢃꢂ
ꢎꢆꢉꢂPJꢁꢂZDVꢂDGGHGꢆꢂ7KHꢂUHDFWLRQꢂPL[WXUHꢂZDVꢂVWLUUHGꢂDWꢂꢊꢑƒ&ꢂDQGꢂWKHꢂ
UHDFWLRQꢂPRQLWRUHGꢂE\ꢂ7/&ꢆꢂ$IWHUꢂFRPSOHWLRQꢂWKHꢂUHDFWLRQꢂPL[WXUHꢂ
ZDVꢂTXHQFKHGꢂZLWKꢂZDWHUꢂꢀꢈꢑꢂPOꢁꢂDQGꢂH[WUDFWHGꢂZLWKꢂ&+2Cl2 (10 ml).
7KHꢂ RUJDQLFꢂ SKDVHꢂ ZDVꢂ ZDVKHGꢂ ZLWKꢂ EULQHꢂ DQGꢂ GULHGꢂ RYHUꢂ VRGLXPꢂ
VXOIDWHꢆꢂ$IWHUꢂFRQFHQWUDWLRQꢂXQGHUꢂUHGXFHGꢂSUHVVXUHꢃꢂWKHꢂUHVLGXHꢂZDVꢂ
SXUL¿HGꢂE\ꢂVLOLFDꢂJHOꢂFROXPQꢂFKURPDWRJUDSK\ꢂXVLQJꢂSHWUROHXPꢂHWKHU±
HWK\OꢂDFHWDWHꢂꢀꢈꢑꢂꢐꢂꢈꢁꢂDVꢂHOXHQWꢂWRꢂDIIRUGꢂ3aꢂꢀꢑꢆꢌꢊꢂJꢃꢂ\LHOGꢐꢂꢉꢊꢋꢁꢆ
7KHꢂV\QWKHWLFꢂSURFHGXUHꢂIRUꢂ4a ZDVꢂWKHꢂVDPHꢂDVꢂIRUꢂSURGXFWꢂ3a.
N
Sc(OTf)3
NHTs
R
R
R
HOAr
2
1
3
Scheme 3
ascribed the formation of the more stable carbonium in BꢃꢂE\ꢂ
rearrangement of the species A. Phenols attack the more stable
cation to afford the unexpected product 4 LQꢂPRGHUDWHꢂ\LHOGꢆꢂ
2WKHUꢂ SKHQROVꢂ UHDFWHGꢂ ZLWKꢂ VXEVWUDWHꢂ 1d and similar results
ZHUHꢂREWDLQHGꢂꢀTable 3ꢁꢆꢂ,QꢂYLHZꢂRIꢂWKHVHꢂH[SHULPHQWDOꢂIDFWVꢃꢂ
a possible mechanism for the formation of 4 can be proposed
(Scheme 4).
,QꢂVXPPDU\ꢃꢂ6Fꢀ27Iꢁ3ꢅFDWDO\VHGꢂUHJLRVHOHFWLYHꢂULQJꢅRSHQLQJꢂ
RIꢂ D]LULGLQHVꢂ ZLWKꢂ SKHQROVꢂ LVꢂ GHVFULEHGꢃꢂ ZKLFKꢂ SURYLGHVꢂ Dꢂ
FRQYHQLHQWꢂ DSSURDFKꢂ WRꢂ WKHꢂ V\QWKHVLVꢂ RI WHUWLDU\ꢂ DON\O±DU\Oꢂ
ethers. Further investigations of the scope of the reaction are
FXUUHQWO\ꢂXQGHUZD\ꢆ
Spectroscopic data for obtained compounds (for 3c, 3g, 3k and 4c
M + is given for 35Cl)
4-methyl-N-(2-phenoxy-2-phenylethyl)benzenesulfonamide
(3a):
White solid; m.p. 108.5–109.5°C. [lit.(13): 145ꢀ146°C]. MS (ESI):
m/z(%)=367(M+,2),274(100).IR(KBr)Qmax:3145,1401,1321,1154,
1104 cm-1. 1H NMR (CDCl3ꢃꢂꢎꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢒꢆꢒꢄꢂꢀGꢃꢂꢄ+ꢃꢂJ = 8.0 Hz),
7.23ꢀ7.30 (m, 7H), 7.14 (t, 2H, J = 8.0 Hz), 6.88 (t, 1H, J = 7.2 Hz),
6.71 (d, 2H, J = 8.0 Hz), 5.11 (d, 1H, J = 6.0 Hz), 5.03 (d, 1H, J = 4.4
Hz), 3.38ꢀ3.45 (m, 1H), 3.22ꢀ3.28 (m, 1H), 2.40 (s, 3H), 13C NMR
(CDCl3ꢃꢂꢈꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢊꢒꢆꢄꢃꢂꢈꢎꢌꢆꢊꢃꢂꢈꢌꢒꢆꢉꢃꢂꢈꢌꢒꢆꢈꢃꢂꢈꢄꢉꢆꢓꢂꢀ&+ꢂîꢂꢄꢁꢃꢂ
129.3 (CH × 2), 128.8 (CH × 2), 128.4, 127.0 (CH × 2), 126.0 (CH ×
2), 121.4, 115.8 (CH × 2), 78.5, 49.5, 21.5.
4-methyl-N-(2-phenyl-2-(m-tolyloxy)ethyl)benzenesulfonamide
(3b): White solid; m.p. 95.5ꢀ97.5°C. MS (ESI): m/z (%) = 381 (M+, 3),
274 (100). Anal. Calcd for C22H23NO3S: C, 69.26; H, 6.08; N, 3.67;
Found: C, 69.15; H, 6.1; N, 3.55. IR (KBr) Qmax: 3145, 1400, 1320,
1157, 1091 cm-1. 1H NMR (CDCl3ꢃꢂ ꢎꢑꢑꢂ 0+]ꢁꢐꢂ įꢂ ꢂ ꢒꢆꢒꢄꢂ ꢀGꢃꢂ ꢄ+ꢃꢂ
J = 8.0 Hz), 7.25ꢀ7.32 (m, 7H), 7.01 (d, 1H, J = 8.0 Hz), 6.70 (d,
1H, J = 8.0 Hz), 6.56 (s, 1H), 6.49 (d, 1H, J = 8.0 Hz), 5.10 (dd,
1H, J = 3.6, 9.2 Hz), 5.02 (brs, 1H), 3.42 (ddd, 1H, J = 3.6, 8.8, 12.8
Hz), 3.23 (ddd, 1H, J = 3.6, 8.8, 12.8 Hz), 2.41 (s, 3H), 2.23 (s, 3H),
13C NMR (CDCl3ꢃꢂꢈꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢊꢒꢆꢄꢃꢂꢈꢎꢌꢆꢊꢃꢂꢈꢌꢉꢆꢎꢃꢂꢈꢌꢓꢆꢈꢃꢂꢈꢌꢒꢆꢄꢃꢂ
129.8 (CH × 2), 129.1, 128.8 (CH × 2), 128.3, 127.0 (CH × 2), 126.0
(CH × 2), 122.3, 116.7, 112.6, 78.4, 49.5, 21.5, 21.4.
Experimental
0HOWLQJꢂ SRLQWVꢂ ZHUHꢂ GHWHUPLQHGꢂ RQꢂ Dꢂ %FKLꢂ %ꢅꢊꢎꢑꢂ PHOWLQJꢂ
DSSDUDWXVꢂDQGꢂDUHꢂXQFRUUHFWHGꢆꢂ7KHꢂ105ꢂVSHFWUDꢂZHUHꢂPHDVXUHGꢂZLWKꢂ
Dꢂ %UXNHUꢂ$GYDQFHꢂ ,,,ꢂ ꢊꢑꢑꢂ RUꢂ 9DULDQꢂ 0HUFXU\ꢂ 3OXVꢅꢎꢑꢑꢂ LQVWUXPHQWꢂ
using CDCl3ꢂ DVꢂ WKHꢂ VROYHQWꢂ ZLWKꢂ 706ꢂ DVꢂ LQWHUQDOꢂ VWDQGDUGꢆꢂ ,5ꢂ
VSHFWUDꢂ ZHUHꢂ UHFRUGHGꢂ XVLQJꢂ .%Uꢂ SHOOHWVꢂ RQꢂ Dꢂ 1LFROHWꢂ$YLDWDUꢅꢌꢒꢑꢂ
LQVWUXPHQWꢆꢂ 0DVVꢂ VSHFWUDꢂ ZHUHꢂ PHDVXUHGꢂ ZLWKꢂ 7KHUPRꢂ )LQQLJDQꢂ
LCQ-Advantage instrument. (OHPHQWDOꢂ DQDO\VLVꢂ ZDVꢂ SHUIRUPHGꢂ
on a VarioEL-III instrument. High resolution mass spectrometric
ꢀ+506ꢁꢂ DQDO\VHVꢂ ZHUHꢂ PHDVXUHGꢂ RQꢂ DQꢂ $3(;ꢂ ꢀ%UXNHUꢁꢂ PDVVꢂ
,,,ꢂ VSHFWURPHWHUꢂ XVLQJꢂ (6,ꢂ ꢀHOHFWURVSUD\ꢂ LRQLVDWLRQꢁꢂ WHFKQLTXHVꢆꢂ
$OOꢂ VSHFWURVFRSLFꢂ GDWDꢂ RIꢂ WKHꢂ SURGXFWVꢂ ZHUHꢂ LGHQWLFDOꢂ WRꢂ WKRVHꢂ RIꢂ
authentic samples.
N-(2-(4-chlorophenoxy)-2-phenylethyl)-4-methylbenzene-sulfonamide
(3c): White solid; m.p. 129.5ꢀ130.5°C. MS (ESI): m/z (%) = 403 ([M
+ 2]+, 1), 401 (M+, 3), 274 (100). Anal. Calcd for C21H20ClNO3S: C,
Sc(OTf)3
Ts
OAr
OAr
N
(1mol%)
6 h
NHTs
NHTs
+
ArOH
+
2
1d
Sc(OTf)3
Sc(OTf)3
3 (trace)
4 (55%-75%)
Sc(OTf)3
TsN
TsN
H-shift
ArOH
A
B
Scheme 4

JOURNAL OF CHEMICAL RESEARCH 2008 299
4-methyl-N-(2-phenoxy-3-phenylpropyl)benzenesulfonamide (3i):
White solid; m.p. 94ꢀ96°C. MS (ESI): m/z (%) = 381 (M+, 23), 380
([M-1]+, 100), 286 (18). Anal. Calcd for C22H23NO3S: C, 69.26; H,
6.08; N, 3.67; Found: C, 69.2; H, 6.15; N, 3.6. IR (KBr) Qmax: 3272,
2925, 1598, 1494, 1150, 1086 cm-1. 1H NMR (CDCl3, 400 MHz):
įꢂ ꢂꢒꢆꢍꢎꢂꢀGꢃꢂꢄ+ꢃꢂJ = 8.0 Hz), 7.20ꢀ7.29 (m, 7H), 7.13 (t, 2H, J = 6.0 Hz),
6.95 (t, 1H, J = 6.0 Hz), 6.79 (d, 2H, J = 8.0 Hz), 4.87 (brs, 1H),
4.43 (d, 1H, J = 4.0 Hz), 3.19 (dd, 1H, J = 4.0, 8.0 Hz), 3.10 (dd, 1H,
J = 4.0, 12.0 Hz), 2.97 (dd, 1H, J = 4.0, 12.0 Hz), 2.84 (dd, 1H,
J = 8.0, 12.0 Hz), 2.41 (s, 3H), 13C NMR (CDCl3, 100 MHz):
įꢂ ꢂꢈꢊꢒꢆꢈꢃꢂꢈꢎꢌꢆꢊꢃꢂꢈꢌꢍꢆꢓꢃꢂꢈꢌꢍꢆꢊꢃꢂꢈꢄꢉꢆꢓꢂꢀ&+ꢂîꢂꢄꢁꢃꢂꢈꢄꢉꢆꢒꢂꢀ&+ꢂîꢂꢄꢁꢃꢂꢈꢄꢉꢆꢎꢂ
(CH × 2), 128.7 (CH × 2), 127.1 (CH × 2), 127.0, 121.8, 116.2 (CH ×
2), 77.3, 45.3, 37.5, 21.5.
Table 3 The reaction of 1d with 2
Entry
ArOH
Yield/%
1
2
3
4
C6H5 (2a)
55 (4a)
56 (4b)
70 (4c)
75 (4d)
m-CH3C6H4 (2b)
p-CIC6H4 (2c)
ß-C10H7 (2e)
62.76; H, 5.02; N, 3.49; Found: C, 62.6; H, 5.1; N, 3.4. IR (KBr) Qmax
:
3134, 1400, 1317, 1155, 1105 cm-1. 1H NMR (CDCl3, 400 MHz):
įꢂ ꢂꢒꢆꢒꢄꢂꢀGꢃꢂꢄ+ꢃꢂJ = 8.4 Hz), 7.23ꢀ7.34 (m, 7H), 7.09 (d, 2H, J = 9.2 Hz),
6.63 (d, 2H, J = 9.2 Hz), 5.06 (dd, 1H, J = 3.6, 9.2 Hz), 4.97ꢀ5.02
(m, 1H), 3.42 (ddd, 1H, J = 3.6, 8.8, 12.8 Hz), 3.26 (ddd, 1H, J = 3.6,
8.8, 12.8 Hz), 2.41 (s, 3H), 13C NMR (CDCl3ꢃꢂꢈꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢊꢒꢆꢄꢃꢂ
143.5, 137.9, 137.1, 129.8 (CH × 2), 129.3 (CH × 2), 128.8 (CH × 2),
128.4, 127.0 (CH × 2), 126.0 (CH × 2), 121.4, 115.8 (CH × 2), 78.5,
49.5, 21.5.
4-methyl-N-(3-phenyl-2-(m-tolyloxy)propyl)benzenesulfonamide
(3j): White solid; m.p. 86ꢀ88°C. MS (ESI): m/z (%) = 395 (M+, 21),
394 ([M-1]+, 100), 332 (68). Anal. Calcd for C23H25NO3S: C, 69.84;
H, 6.37; N, 3.54; Found: C, 69.75; H, 6.5; N, 3.3. IR (KBr) Qmax
:
1
3271, 2976, 2919, 1597, 1489, 1152, 1084 cm-1. H NMR (CDCl3,
ꢎꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢒꢆꢍꢎꢂꢀGꢃꢂꢄ+ꢃꢂJ = 8.0 Hz), 7.25ꢀ7.32 (m, 7H), 7.01 (d,
1H, J = 8.0 Hz), 6.77 (d, 1H, J = 8.0 Hz), 6.60 (s, 1H), 6.59 (d, 1H,
J = 8.0 Hz), 4.87 (brs, 1H), 4.40 (d, 1H, J = 4.0 Hz), 3.18 (dd, 1H,
J = 4.0, 8.0 Hz), 3.09 (dd, 1H, J = 4.0, 12.0 Hz), 2.98 (dd, 1H, J =
4.0, 12.0 Hz), 2.84 (dd, 1H, J = 8.0, 12.0 Hz), 2.41 (s, 3H), 2.30 (s,
3H), 13C NMR (CDCl3ꢃꢂꢈꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢊꢒꢆꢈꢃꢂꢈꢎꢌꢆꢊꢃꢂꢈꢌꢉꢆꢓꢃꢂꢈꢌꢍꢆꢓꢃꢂ
136.6, 129.8, 129.7 (CH × 2), 129.4 (CH × 2), 128.7 (CH × 2), 127.1
(CH × 2), 127.0, 122.6, 117.1, 113.0, 77.3, 45.3, 37.6, 21.5 (CH × 2).
N-(2-(4-chlorophenoxy)-3-phenylpropyl)-4-methylbenzene
sulfonamide (3k): White solid; m.p. 95ꢀ97°C. MS (ESI): m/z
(%) = 417 ([M + 2]+, 6), 415 (M+, 18), 414 (100). Anal. Calcd for
C22H22ClNO3S: C, 63.53; H, 5.33; N, 3.37; Found: C, 63.45; H, 5.6;
N, 3.2. IR (KBr) Qmax: 3264, 2922, 1596, 1490, 1149, 1092 cm-1.
1H NMR (CDCl3ꢃꢂꢎꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢒꢆꢍꢎꢂꢀGꢃꢂꢄ+ꢃꢂJ = 8.0 Hz), 7.19ꢀ7.28
(m, 5H), 7.15 (d, 2H, J = 8.0 Hz), 7.11 (d, 2H, J = 8.0 Hz), 6.68 (d,
2H, J = 8.0 Hz), 4.96 (brs, 1H), 4.39 (dd, 1H, J = 4.0 Hz), 3.18 (dd,
1H, J = 4.0, 8.0 Hz), 3.10 (dd, 1H, J = 4.0, 12.0 Hz), 2.94 (dd, 1H,
J = 4.0, 12.0 Hz), 2.84 (dd, 1H, J = 8.0, 12.0 Hz), 2.41 (s, 3H), 13C
NMR (CDCl3ꢃꢂꢈꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢊꢒꢆꢈꢃꢂꢈꢎꢌꢆꢍꢃꢂꢈꢌꢍꢆꢒꢃꢂꢈꢌꢍꢆꢄꢃꢂꢈꢄꢉꢆꢓꢂꢀ&+ꢂ
× 2), 129.7 (CH × 2), 129.4 (CH × 2), 128.8 (CH × 2), 127.1 (CH ×
2), 127.0, 126.5, 117.5 (CH × 2), 77.8, 45.3, 37.5, 21.5.
4-methyl-N-(2-(4-nitrophenoxy)-2-phenylethyl)benzenesulfonamide
(3d): White solid; m.p. 185.5ꢀ187.0°C. MS (ESI): m/z (%) = 412
(M+, 1), 367 (4), 274 (30), 155 (100). Anal. Calcd for C21H20N2O5S:
C, 61.15; H, 4.89; N, 6.79; Found: C, 60.9; H, 5.0; N, 6.7. IR (KBr)
Qmax: 3313, 2932, 1593, 1315, 1161, 1109 cm-1. 1H NMR (CDCl3,
ꢎꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢓꢆꢑꢊꢂꢀGꢃꢂꢄ+ꢃꢂJ = 9.2 Hz), 7.72 (d, 2H, J = 8.0 Hz),
7.31ꢀ7.37 (m, 3H), 7.25ꢀ7.29 (m, 4H), 6.79 (d, 2H, J = 9.2 Hz), 5.27
(dd, 1H, J = 3.6, 8.8 Hz), 5.06 (brs, 1H), 3.45 (ddd, 1H, J = 4.0,
8.8, 13.6 Hz), 3.34 (ddd, 1H, J = 4.8, 8.8, 13.6 Hz), 2.40 (s, 3H),
13C NMR (CDCl3ꢃꢂꢈꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢍꢄꢆꢄꢃꢂꢈꢎꢌꢆꢓꢃꢂꢈꢎꢈꢆꢓꢃꢂꢈꢌꢒꢆꢑꢃꢂꢈꢌꢍꢆꢎꢃꢂ
129.8 (CH × 2), 129.2 (CH × 2), 129.0, 127.0 (CH × 2), 126.0 (CH ×
2), 125.7 (CH × 2), 115.3 (CH × 2), 73.5, 47.8, 21.5.
4-methyl-N-(2-phenoxypropyl)benzenesulfonamide (3e): White
solid; m.p. 80.1ꢀ82.5°C. MS (ESI): m/z (%) = 305 (M+, 20), 212
(100). Anal. Calcd for C16H19NO3S: C, 62.93; H, 6.27; N, 4.59;
Found: C, 62.7; H, 6.35; N, 4.5. IR (KBr) Qmax: 3293, 2917, 1325,
1155, 1089 cm-1. 1H NMR (CDCl3ꢃꢂ ꢎꢑꢑꢂ 0+]ꢁꢐꢂ įꢂ ꢂ ꢒꢆꢒꢌꢂ ꢀGꢃꢂ ꢄ+ꢃꢂ
J = 7.6 Hz), 7.27 (d, 2H, J = 8.0 Hz), 7.23 (d, 2H, J = 8.0 Hz), 6.95
(t, 1H, J = 7.2 Hz), 6.78 (d, 2H, J = 8.4 Hz), 4.98 (dd, 1H, J = 4.4,
7.6 Hz), 4.39ꢀ4.43 (m, 1H), 3.26 (ddd, 1H, J = 3.6, 8.0, 12.4 Hz),
3.06 (ddd, 1H, J = 4.8, 7.6, 12.8 Hz), 2.42 (s, 3H), 1.22 (d, 3H,
J = 6.0 Hz), 13C NMR (CDCl3ꢃꢂꢈꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢊꢒꢆꢑꢃꢂꢈꢎꢌꢆꢊꢃꢂꢈꢌꢒꢆꢑꢃꢂ
129.8 (CH × 2), 129.6 (CH × 2), 127.0 (CH × 2), 121.5, 116.0 (CH ×
2), 72.4, 48.0, 21.5, 17.1.
4-methyl-N-(3-methyl-3-phenoxybutyl)benzenesulfonamide (4a):
/LJKWꢂ\HOORZꢂOLTXLGꢆꢂ06ꢂꢀ(6,ꢁꢐꢂm/z (%) = 334 ([M + 1]+, 13), 240
(92), 184 (100). HRMS (ESI) Calcd for C18H23NO3S (M + 1)+,
334.1471. Found: (M + 1)+, 334.1472. IR (KBr) Qmax: 3131, 2978,
1401, 1160, 1094 cm-1. 1H NMR (CDCl3ꢃꢂꢎꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢒꢆꢒꢒꢂꢀGꢃꢂꢄ+ꢃꢂ
J = 8.0 Hz), 7.31 (d, 2H, J = 8.0 Hz), 7.25 (t, 2H, J = 7.6 Hz), 7.10
(t, 1H, J = 7.6 Hz), 6.86 (d, 2H, J = 7.8 Hz), 5.29 (brs, 1H), 3.23 (dd,
2H, J = 6.4, 12.0 Hz), 2.44 (s, 3H), 1.84 (t, 2H, J = 6.8 Hz), 1.18 (s,
6H), 13C NMR (CDCl3ꢃꢂꢈꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢊꢎꢆꢈꢃꢂꢈꢎꢌꢆꢌꢃꢂꢈꢌꢍꢆꢉꢃꢂꢈꢄꢉꢆꢒꢂ
(CH × 2), 129.0 (CH × 2), 127.2 (CH × 2), 124.1 (CH × 2), 124.0,
80.4, 41.0, 39.6, 26.3 (CH × 2), 21.5.
4-methyl-N-(3-methyl-3-(m-tolyloxy)butyl)benzenesulfonamide
(4bꢁꢐꢂ/LJKWꢂ\HOORZꢂOLTXLGꢆꢂ06ꢂꢀ(6,ꢁꢐꢂm/z (%) = 370 ([M + Na]+, 100).
HRMS (ESI) Calcd for C19H25NO3S (M + 1)+, 348.1628. Found: (M
+ 1)+, 348.1624. IR (KBr) Qmax: 3285, 2977, 2928, 1600, 1485, 1160,
1094 cm-1. 1H NMR (CDCl3ꢃꢂꢊꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢒꢆꢒꢒꢂꢀGꢃꢂꢄ+ꢃꢂJ = 8.0 Hz),
7.31(d, 2H, J=8.0Hz), 7.12(t, 1H, J=7.5Hz), 6.91(d, 1H, J=7.5Hz),
6.67 (s, 1H), 6.66 (m, 1H, J = 8.0 Hz), 5.34 (d, 1H, J = 5.0 Hz),
3.22 (dd, 2H, J = 6.0, 12.0 Hz), 2.44 (s, 3H), 2.31 (s, 3H), 1.83 (t, 2H,
J = 6.5 Hz), 1.17 (s, 6H), 13C NMR (CDCl3ꢃꢂꢈꢄꢊꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢊꢎꢆꢈꢃꢂ
143.2, 139.0, 137.0, 129.7 (CH × 2), 128.7, 127.2 (CH × 2), 124.8,
124.7, 121.0, 80.3, 41.0, 39.6, 26.3 (CH × 2), 21.5, 21.4.
N-(3-(4-chlorophenoxy)-3-methylbutyl)-4-methylbenzene-
sulfonamide (4cꢁꢐꢂ /LJKWꢂ \HOORZꢂ OLTXLGꢆꢂ 06ꢂ ꢀ(6,ꢁꢐꢂ m/z (%) = 370
([M + 3]+, 33), 368 ([M + 1]+, 100). HRMS (ESI) Calcd for
C18H22ClNO3S (M + 1)+, 368.1082. Found: (M + 1)+, 368.1076. IR
(KBr)Qmax:3286,2977,2928,1488,1160,1093cm-1.1HNMR(CDCl3,
ꢊꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢒꢆꢒꢍꢂꢀGꢃꢂꢄ+ꢃꢂJ = 8.0 Hz), 7.32 (d, 2H, J = 8.0 Hz),
7.20 (dd, 2H, J = 2.0, 7.0 Hz), 6.79 (dd, 2H, J = 2.0, 7.0 Hz), 5.26
(t, 1H, J = 5.5 Hz), 3.20 (dd, 2H, J = 6.5, 12.5 Hz), 2.44 (s, 3H),
1.83 (t, 2H, J = 7.0 Hz), 1.16 (s, 6H), 13C NMR (CDCl3, 125 MHz):
įꢂ ꢂꢈꢊꢄꢆꢓꢃꢂꢈꢎꢌꢆꢎꢃꢂꢈꢌꢍꢆꢉꢃꢂꢈꢄꢉꢆꢒꢂꢀ&+ꢂîꢂꢄꢁꢃꢂꢈꢄꢉꢆꢄꢃꢂꢈꢄꢉꢆꢈꢂꢀ&+ꢂîꢂꢄꢁꢃꢂꢈꢄꢒꢆꢄꢂ
(CH × 2), 125.4 (CH × 2), 80.8, 41.0, 39.4, 26.3 (CH × 2), 21.6.
4-methyl-N-(3-methyl-3-(naphthalen-2-yloxy)butyl)benzenesulfon-
amide (4d): White solid; m.p. 95.0ꢀ96.7°C. MS (ESI): m/z (%) = 407
([M + Na]+, 100). Anal. Calcd for C22H25NO3S: C, 68.90; H, 6.57;
N, 3.65; Found: C, 68.85; H, 6.6; N, 3.6. IR (KBr) Qmax: 3246, 2972,
1401, 1151, 1095 cm-1. 1H NMR (CDCl3ꢃꢂꢊꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢒꢆꢓꢈꢂꢀGꢃꢂꢈ+ꢃꢂ
J = 8.0 Hz), 7.78 (d, 2H, J = 8.0 Hz), 7.72ꢀ7.75 (m, 2H), 7.47 (ddd,
1H, J = 1.0, 6.5, 8.0 Hz), 7.42 (ddd, 1H, J = 1.0, 6.5, 8.0 Hz), 7.32
4-methyl-N-(2-(m-tolyloxy)propyl)benzenesulfonamide
(3f):
White solid; m.p. 76.5ꢀ78.1°C. MS (ESI): m/z (%) = 319 (M+, 30),
212 (100). Anal. Calcd for C17H21NO3S: C, 63.92; H, 6.63; N, 4.39;
Found: C, 63.8; H, 6.7; N, 4.25. IR (KBr) Qmax: 3131, 2978, 2925,
1401, 1160, 1091 cm-1. 1H NMR (CDCl3ꢃꢂꢎꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢒꢆꢒꢄꢂꢀGꢃꢂꢄ+ꢃꢂ
J = 8.4 Hz), 7.27 (d, 2H, J = 8.0 Hz), 7.12 (t, 1H, J = 7.6 Hz), 6.77 (d,
1H, J = 7.6 Hz), 6.59 (s, 1H), 6.58 (d, 1H, J = 8.8 Hz), 4.93 (brs, 1H),
4.36ꢀ4.40 (m, 1H), 3.25 (ddd, 1H, J = 3.6, 8.0, 12.8 Hz), 3.05 (ddd,
1H, J = 4.4, 7.6, 12.4 Hz), 2.42 (s, 3H), 2.29 (s, 3H), 1.21 (d, 3H,
J = 6.0 Hz), 13C NMR (CDCl3ꢃꢂꢈꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢊꢒꢆꢑꢃꢂꢈꢎꢌꢆꢎꢃꢂꢈꢌꢉꢆꢍꢃꢂ
137.1, 129.7 (CH × 2), 129.3, 127.0 (CH × 2), 122.3, 116.9, 112.9,
72.4, 48.0, 21.5, 21.4, 14.1.
N-(2-(4-chlorophenoxy)propyl)-4-methylbenzenesulfonamide
(3g): White solid; m.p. 77.5ꢀ79.0°C. MS (ESI): m/z (%) = 341
([M + 2]+, 5), 339 (M+, 15), 212 (95), 155 (100). Anal. Calcd for
C16H18ClNO3S: C, 56.55; H, 5.34; N, 4.12; Found: C, 56.4; H, 5.4;
N, 4.0. IR (KBr) Qmax: 3266, 2924, 1320, 1150, 1086 cm-1. 1H NMR
(CDCl3ꢃꢂꢎꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢒꢆꢒꢄꢂꢀGꢃꢂꢄ+ꢃꢂJ = 8.0 Hz), 7.26 (d, 2H, J = 8.4
Hz), 7.17 (d, 2H, J = 8.8 Hz), 6.71 (d, 2H, J = 9.2 Hz), 5.02 (dd, 1H,
J = 4.4, 7.2 Hz), 4.32ꢀ4.37 (m, 1H), 3.24 (ddd, 1H, J = 3.6, 8.0, 12.4
Hz), 3.06 (ddd, 1H, J = 4.8, 7.2, 12.8 Hz), 2.42 (s, 3H), 1.21 (d, 3H,
J = 6.4 Hz), 13C NMR (CDCl3ꢃꢂꢈꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢊꢊꢆꢍꢃꢂꢈꢎꢌꢆꢍꢃꢂꢈꢌꢒꢆꢑꢃꢂ
129.8 (CH × 2), 129.7 (CH × 2), 127.0 (CH × 2), 126.4, 117.3 (CH ×
2), 73.0, 47.9, 21.5, 17.0.
4-methyl-N-(2-(4-nitrophenoxy)propyl)benzenesulfonamide (3h):
White solid; m.p. 126.2ꢀ128.1°C. MS (ESI): m/z (%) = 350 (M+, 10),
212 (40), 155 (100). Anal. Calcd for C16H18N2O5S: C, 54.85; H, 5.18;
N, 7.99; Found: C, 54.7; H, 5.3; N, 7.85. IR (KBr) Qmax: 3266, 1593,
1318, 1149, 1088 cm-1. 1H NMR (CDCl3ꢃꢂꢎꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢓꢆꢈꢍꢂꢀGꢃꢂ
2H, J = 9.2 Hz), 7.73 (d, 2H, J = 8.0 Hz), 7.28 (d, 2H, J = 8.4 Hz),
6.85 (d, 2H, J = 9.2 Hz), 4.90 (t, 1H, J = 6.0 Hz), 4.55ꢀ4.59 (dd, 1H,
J = 6.8, 10.4 Hz), 3.29 (ddd, 1H, J = 3.6, 8.0, 12.4 Hz), 3.14 (ddd,
1H, J = 4.0, 7.6, 12.8 Hz), 2.42 (s, 3H), 1.29 (d, 3H, J = 6.0 Hz), 13
C
NMR (CDCl3ꢃꢂꢈꢑꢑꢂ0+]ꢁꢐꢂįꢂ ꢂꢈꢍꢄꢆꢄꢃꢂꢈꢎꢌꢆꢓꢃꢂꢈꢎꢈꢆꢓꢃꢂꢈꢌꢒꢆꢈꢃꢂꢈꢄꢉꢆꢓꢂꢀ&+ꢂ
× 2), 127.0 (CH × 2), 126.0 (CH × 2), 115.3 (CH × 2), 73.5, 47.8,
21.5, 16.9.

300 JOURNAL OF CHEMICAL RESEARCH 2008
4
5
6
Y. Fukuta, T. Mita, N. Fukuda, M. Kanai and M. Shibasaki, J. Am. Chem.
Soc., 2006, 128, 6312.
(d, 2H, J = 8.0 Hz), 7.27 (d, 1H, J = 2.5 Hz), 7.05 (d, 1H, J = 2.5,
9.0 Hz), 5.28 (t, 1H, J = 5.5 Hz), 3.28 (dd, 2H, 6.5, 10.5 Hz), 2.45
(s, 3H), 1.91 (t, 2H, J = 6.5 Hz), 1.25 (s, 6H), 13C NMR (CDCl3, 125
0+]ꢁꢐꢂįꢂ ꢂꢈꢊꢈꢆꢉꢃꢂꢈꢎꢌꢆꢌꢃꢂꢈꢌꢍꢆꢉꢃꢂꢈꢌꢎꢆꢑꢃꢂꢈꢌꢑꢆꢊꢃꢂꢈꢄꢉꢆꢒꢂꢀ&+ꢂîꢂꢄꢁꢃꢂꢈꢄꢓꢆꢉꢂ
(CH × 2), 127.6, 127.2 (CH × 2), 126.3, 124.9, 124.5, 120.0, 81.0,
41.1, 39.6, 26.4 (CH × 2), 21.6.
S. Minakata, T. Hotta, Y. Oderaotoshi and M. Komatsu, J. Org. Chem.,
2006, 71, 7471.
J.X. Chen, H.Y. Wu, C. Jin, X.X. Zhang, Y.Y. Xie and W.K. Su, Green
Chem., 2006, 8, 330.
W.K. Su, J.X. Chen, H.Y. Wu and C. Jin, J. Org. Chem., 2007, 72, 4524.
D. Tanner, Angew. Chem. Inter. Ed. Engl., 1994, 33, 599.
M. Kasai and M. Kono, Synlett, 1992, 778.
7
8
9
We thank the National Natural Science Foundation of China
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>ꢄꢑꢑꢒ%$,ꢌꢎ%ꢑꢄ@ꢂIRUꢂ¿QDQFLDOꢂVXSSRUWꢆ
ꢂꢈꢑꢂ +ꢆ0ꢆ,ꢆꢂ2VERUQꢂDQGꢂ-ꢆꢂ6ZHHQH\ꢃꢂTetrahedron: Asymmetry, 1997, 8, 1693.
ꢂꢈꢈꢂ &ꢆ0ꢆꢂ5D\QHUꢃꢂSynlett, 1997, 11.
12 W. McCoull and F.A. Davis, Synthesis, 2000, 1347.
13 B.A.B. Prasad, R. Sanghi and V.K. Singh, Tetrahedron, 2002, 58, 7355.
14 K.G.D. Kumar and S. Baskaran, Synlett, 2004, 1719.
15 X.L. Hou, R.H. Fan and L.X. Dai, J. Org. Chem., 2002, 67, 5295.
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17 P. Li, E.M. Forbeck, C.D. Evans and M.M. Joullie, Org. Lett., 2006, 8,
5105.
Received 17 January 2008; accepted 27 April 2008
Paper 08/5043 doi: 10.3184/030823408X320610
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