3
332 J . Org. Chem., Vol. 65, No. 11, 2000
Imai et al.
CDCl
3
) major: δ 3.63 (m, 2H), 3.75 (m, 2H), 4.91 (m, 2H), 6.90-
presence of triethylamine (8.0 mL, 57.4 mmol) in dry dichlo-
7
.62 (m, 20H); minor: δ 3.57 (m, 4H), 5.00 (m, 2H), 6.90-7.62
romethane (70 mL) afforded 1d (5.2 g, 11.0 mmol, 85% yield)
-
1
1
(m, 20H). IR (KBr, cm ) 1539, 1633. MS (CI) m/z 481 ([M +
as a colorless viscous liquid. The H NMR of 1a showed two
+
sets of signals: major/minor (70:30). 1H NMR (400 MHz,
1
] ).
,2′-Bis[N-(1′S)-(1′-ben zyl-2′-h yd r oxyeth yl)ca r boxa m -
2
3
CDCl ) major: δ 2.62 (q, 2H, J 8.4, 13.8 Hz), 2.96 (dd, 2H, J
id o]-1,1′-bip h en yl (4d ). Following a procedure identical to
that described for the preparation of 4a , the reaction of (S)-
phenylalaninol (6.3 g, 41.7 mmol) with 3 (5.0 g, 17.9 mmol) in
the presence of triethylamine (8.0 mL, 57.4 mmol) in dry
dichloromethane (70 mL) afforded 4d (6.6 g, 13.0 mmol, 73%
5.4, 13.8 Hz), 3.81 (t, 2H, J 7.8 Hz), 4.11 (t, 2H, J 9.0 Hz),
4.37 (m, 2H), 7.13-7.47 (m, 16H), 7.80 (d, 2H, J 7.8 Hz).
minor: δ 2.56 (q, 2H, J 9.0, 13.8 Hz), 3.07 (dd, 2H, J 5.4, 13.8
Hz), 3.87 (t, 2H, J 7.8 Hz), 3.98 (t, 2H, J 9.0 Hz), 4.37 (m, 2H),
-
1
7.13-7.47 (m, 16H), 7.87 (d, 2H, J 7.8 Hz). IR (neat, cm
)
1
26
yield) as a yellow solid. The H NMR of 4d also showed two
1649. [R]
D
) -208.2 (c 0.50, CHCl
472.2152, found 472.2144. Anal. Calcd for
O: C, 78.06; H, 6.18; N, 5.69. Found: C,
3
). HRMS (EI) calcd for
1
sets of signals. Major/minor (52:48). H NMR (400 MHz,
C
C
32
H
H
28
N
N
2 2
O :
CDCl
3
) major: δ 2.39 (m, 2H), 2.64 (m, 2H), 3.19-4.00 (m,
32
28
2
O
2
‚0.1H
2
6
2
2
1
H), 6.75-7.31 (m, 20H), 7.36 (m, 2H); minor: δ 2.39 (m, 2H),
77.81; H, 5.95; N, 5.54.
.64 (m, 2H), 3.19-4.00 (m, 6H), 6.75-7.31 (m, 20H), 7.42 (m,
2,2′-Bis[(4′S)-isopr opyloxazolin -2′-yl]-1,1′-biph en yl Cop-
p er (I) Tr ifla te Com p lex (6a , M ) Cu (OTf)). To a solution
-
1
H). IR (KBr, cm ) 1539, 1651, 3244. MS (CI) m/z 509 ([M +
+
] ).
of ligand 1a (3.8 mg, 10.1 µmol) in dichloromethane-d
2
was
6 6
H )0.5] (2.6 mg, 10.3 µmol), and
2
,2′-Bis[(4′S)-isopr opyloxazolin -2′-yl]-1,1′-biph en yl (1a).
added 1 equiv of [Cu(I)OTf(C
A solution of methanesulfonyl chloride (2.5 mL, 32.3 mmol)
in dry dichloromethane (5 mL) was added dropwise for 1 h to
a solution of crude 4a (5.7 g, 13.8 mmol) in the presence of
triethylamine (8.0 mL, 57.4 mmol) in dry dichloromethane (50
mL) with stirring at -5 °C. After being stirred for 4 h at room
temperature, the resulting mixture was washed with water
and then brine, dried over magnesium sulfate, and then
concentrated in vacuo. The residue was purified by silica gel
column chromatography with ethyl acetate as an eluent to give
the suspension was stirred at room temperature under argon
atmosphere until complete dissolution. The 1H NMR of this
solution showed only one set of signals. (S,aS,S)-6a (M ) Cu-
(OTf)): 1H NMR (400 MHz, CD
Cl ) δ 0.42 (d, 6H, J 6.8 Hz),
2 2
0.47 (d, 6H, J 6.8 Hz), 1.47 (m, 2H), 4.03 (m, 2H), 4.31 (m,
2H), 4.54 (t, 2H, J 9.4 Hz), 7.06 (m, 2H), 7.41 (m, 4H), 7.60
+
(m, 2H). MS (FAB) m/z 439 ([M - OTf] ).
2,2′-Bis[(4′S)-ter t-bu tyloxazolin -2′-yl]-1,1′-biph en yl Cop-
1
p er (I) Tr ifla te Com p lex (6b, M ) Cu (OTf)). The H NMR
1
a (4.3 g, 11.4 mmol, 83% yield) as a colorless viscous liquid.
of 6b showed only one set of signals. (S,aS,S)-6b (M ) Cu-
1
(OTf)): 1H NMR (400 MHz, CD
2H), 4.43 (m, 2H), 4.53 (t, 2H, J 9.6 Hz), 7.05 (m, 2H), 7.41
(m, 4H), 7.67 (m, 2H). MS (FAB) m/z 467 ([M - OTf] ).
2,2′-Bis[(4′S)-p h en yloxa zolin -2′-yl]-1,1′-bip h en yl Cop -
The H NMR of 1a showed two sets of signals. major/minor
2 2
Cl ) δ 0.53 (s, 18H), 4.04 (m,
1
(
1
71:29). H NMR (600 MHz, CDCl
.69 (m, 2H), 3.74 (t, 2H, J 7.8 Hz), 3.85 (m, 2H), 4.13 (t, 2H,
J 9.3 Hz), 7.32 (d, 2H, J 7.2 Hz), 7.37 (m, 2H), 7.47 (t, 2H, J
3
) major: δ 0.81(m, 12H),
+
1
7
6
.2 Hz), 7.80 (d, 2H, J 7.8 Hz); minor: δ 0.81 (m, 6H), 0.87 (d,
H, J 6.6 Hz), 1.64 (m, 2H), 3.85 (m, 4H), 4.01 (t, 2H, J 7.2
p er (I) Tr ifla te Com p lex (6c, M ) Cu (OTf)). The H NMR
of 6c showed only one set of signals. (S,aS,S)-6c (M ) Cu-
1
Hz), 7.23 (d, 2H, J 7.2 Hz), 7.37 (m, 2H), 7.40 (t, 2H, J 7.2
(OTf)): H NMR (400 MHz, CDCl
3
) δ 4.36 (q, 2H, J 7.4, 9.0
-
1
26
Hz), 7.86 (d, 2H, J 7.2 Hz). IR (neat, cm ) 1657. [R]
141.5 (c 0.50, CHCl ). HRMS (EI) calcd for C24
76.2152, found 376.2156. Anal. Calcd for
.5H O: C, 74.78; H, 7.58; N, 7.27. Found: C, 74.98; H, 7.53;
D
)
2
Hz), 4.82 (q, 2H, J 9.0, 10.2 Hz), 5.27 (q, 2H, J 7.4, 10.2 Hz),
6.58 (m, 4H), 7.01 (m, 4H), 7.08 (m, 2H), 7.16 (m, 2H), 7.43-
7.51 (m, 4H), 7.57 (dd, 2H, J 1.6, 7.6 Hz). MS (FAB) m/z 507
-
3
0
3
H
28
N
2
O
:
C
24
H
28
N
2
O
2
+
2
([M - OTf] ).
N, 7.17.
2,2′-Bis[(4′S)-ben zyloxa zolin -2′-yl]-1,1′-bip h en yl Cop -
1
2
,2′-Bis[(4′S)-ter t-bu tyloxazolin -2′-yl]-1,1′-biph en yl (1b).
p er (I) Tr ifla te Com p lex (6d , M ) Cu (OTf)). The H NMR
Following a procedure identical to that described for the
preparation of 1a , the reaction of crude 4b (1.1 g, 2.5 mmol)
with methanesulfonyl chloride (0.5 mL, 6.5 mmol) in the
presence of triethylamine (1.5 mL, 10.8 mmol) in dry dichlo-
romethane (25 mL) afforded 1b (0.9 g, 2.2 mmol, 89% yield)
of 6d showed only one set of signals. (S,aS,S)-6d (M ) Cu-
(OTf)): 1H NMR (400 MHz, CDCl
) δ 1.93 (dd, 2H, J 5.4, 13.4
3
Hz), 2.50 (dd, 2H, J 5.4, 13.4 Hz), 4.30 (m, 2H), 4.44 (m, 4H),
6.83 (m, 4H), 7.08-7.14 (m, 8H), 7.42-7.51 (m, 4H), 7.59 (m,
+
2H). MS (FAB) m/z 535 ([M - OTf] ).
1
as a colorless viscous liquid. The H NMR of 1b showed two
Typ ica l P r oced u r e for Cop p er (I)-Ca ta lyzed Asym -
1
sets of signals: major/minor (68:32). H NMR (600 MHz,
m etr ic Cyclop r op a n a tion of Styr en e. To a copper(I) triflate
CDCl
3
) major: δ 0.79 (s, 18H), 3.78 (t, 2H, J 8.6 Hz), 3.83 (m,
6 6
benzene complex [Cu(I)OTf(C H )0.5] (2.6 mg, 10.3 µmol) was
2
H), 4.07 (t, 2H, J 8.6 Hz), 7.27 (m, 2H), 7.37 (m, 2H), 7.44
added a solution of ligand 1 (11.0 µmol) in dichloromethane
(1.0 mL), and then the suspension was stirred at room
temperature for 2 h under argon atmosphere. The resulting
solution was filtered through a membrane filter. After addition
of styrene (104.2 mg, 1.0 mmol), a solution of ethyl or l-menthyl
diazoacetate (1.3 mmol) in dichloromethane (1.0 mL) was
slowly added over a period of 4 h, and then the reaction
solution was stirred at room temperature for additional 24 h.
The reaction mixture was filtered through an alumina short
column, and the filtrate was concentrated in vacuo to give an
oil which was chromatographed on a silica gel column with
hexane/ethyl acetate (9:1) to separate trans- and cis-cycropro-
pane carboxylates 11a -c. The ratio of the trans- and cis-
products was determined by GC with DB-1 of the oil before
chromatography. The enantiomeric excess of 11a -c was
determined by GC with Chiraldex G-TA and DB-1. Absolute
configuration of trans- and cis-11a was determined by com-
(
m, 2H), 7.84 (d, 2H, J 7.8 Hz); minor: δ 0.79 (s, 18H), 3.83
(m, 2H), 3.94 (m, 4H), 7.21 (d, 2H, J 7.2 Hz), 7.37 (m, 4H),
.88 (d, 2H, J 7.8 Hz). IR (neat, cm-1) 1655. [R]
.50, CHCl
26
) -101.4 (c
7
0
D
3
). HRMS (EI) calcd for C26
H
32
N
2
O
2
:
404.2466,
found 404.2474. Anal. Calcd for C26
H
32
N
2
O
2
0.5H
2
O: C, 75.51;
H, 8.04; N, 6.77. Found: C, 75.35; H, 7.89; N, 6.44.
,2′-Bis[(4′S)-p h en yloxa zolin -2′-yl]-1,1′-bip h en yl (1c).
2
Following a procedure identical to that described for the
preparation of 1a , the reaction of crude 4c (6.2 g, 12.9 mmol)
with methanesulfonyl chloride (2.5 mL, 32.3 mmol) in the
presence of triethylamine (8.0 mL, 57.4 mmol) in dry dichlo-
romethane (55 mL) afforded 1c (5.0 g, 11.3 mmol, 87% yield)
1
as a colorless viscous liquid. The H NMR of 1a showed two
sets of signals. major/minor (69:31). H NMR (400 MHz, CDCl
1
3
)
major: δ 3.89 (t, 2H, J 8.4 Hz), 4.51 (q, 2H, J 8.4, 10.1 Hz),
.22 (m, 2H), 7.14-7.98 (m, 18H); minor: δ 4.00 (t, 2H, J 8.4
Hz), 4.41 (q, 2H, J 8.4, 10.2 Hz), 5.22 (m, 2H), 7.14-7.98 (m,
5
1
3
parison of their specific rotation with the reported one. The
absolute configuration of trans- and cis-11b,c was determined
after the transesterification of trans- and cis-11b,c to trans-
and cis-11a , respectively, in the presence of a sulfuric acid
catalyst.
8H). IR (neat, cm-1) 1645. [R]
HRMS (EI) calcd for C30
Anal. Calcd for C30
26
1
D
3
) -194.6 (c, 0.50, CHCl ).
H
24
N
2
O
2
: 444.1839, found 444.1845.
O: C, 79.13; H, 5.58; N, 6.15.
H
24
N
2
O
2
0.6H
2
Found: C, 79.40; H, 5.64; N, 6.00.
,2′-Bis[(4′S)-ben zyloxa zolin -2′-yl]-1,1′-bip h en yl (1d ).
2
Typ ica l P r oced u r e for th e Zin c(II)-Ca ta lyzed Asym -
m etr ic Allyla tion of Ald eh yd e. To a stirred solution of
ligand 1 (0.1 mmol) in dichloromethane (5 mL) was added zinc-
(II) salt (0.1 mmol), and the resulting mixture was stirred for
Following a procedure identical to that described for the
preparation of 1a , the reaction of crude 4d (6.6 g, 13.0 mmol)
with methanesulfonyl chloride (2.5 mL, 32.3 mmol) in the