4
724 J . Org. Chem., Vol. 63, No. 14, 1998
Baldwin et al.
a starting material and alternative transition structures
appear to be essential aspects of the mechanism.
1-Acetyl-7-en d o-p h en ylbicyclo[4.1.0]h ep ta n e (14-en d o)
was obtained by preparative gas chromatography (10% SE-
1
3
0, 125 °C). H NMR δ 0.71-0.85 (m, 1 H), 0.85-0.99 (m, 1
H), 1.05-1.26 (m, 2 H), 1.51-1.63 (m, 1 H), 1.82-2.03 (m, 3
Exp er im en ta l Section
13
H), 2.25 (s, 3 H), 7.18-7.24 (m, 3 H), 7.29-7.36 (m, 2 H);
C
NMR δ 20.1, 20.8, 20.9, 21.0, 25.6, 26.4, 34.1, 34.7, 126.5, 130.7,
Elemental analyses were done by E & R Microanalytical
Laboratory, Corona, NY 11368. The high-resolution mass
spectrum was secured through the University of Illinois School
+
1
(
36.3, 209.6; MS m/z (rel intensity) 214 (18, M ), 199 (21), 171
33), 129 (74), 115 (31), 91 (81), 43 (100). Anal. Calcd for
18O: C, 84.07; H, 8.47. Found: C, 84.14; H, 8.54.
1-Eth yn yl-7-exo-p h en ylbicyclo[4.1.0]h ep ta n e (15). To
1
15
C H
of Chemical Sciences, Urbana, IL 61801. The H NMR and
1
3
3
C NMR spectra were recorded for CDCl solutions. Deute-
an ice-cooled solution of 2.10 g (9.80 mmol) of ketones was
rium NMR spectra at 92 MHz were recorded at the University
of Akron, Akron, OH 44325. Other instrumentation and
standard procedures used in this work have been detailed
added 14 dissolved in 60 mL of dry benzene slowly with
stirring PCl
5
(2.45 g, 11.8 mmol).16 The reaction mixture was
8
,9,14
stirred 20 h at room temperature and then poured into ice cold
water. The hydrolyzed mixture was extracted with ether (3
elsewhere.
Ben zyl P h en yl Su lfoxid e. Benzyl phenyl sulfide (10.0 g,
0.0 mmol) was added to a mixture of NaIO (10.69 g, 50.0
mmol) and aqueous methanol (2:1 H O:MeOH, 100 mL) at 0
C. The reaction mixture was warmed to room temperature,
stirred for 48 h, and filtered. The filtrate was extracted with
CH Cl
(2 × 50 mL), and the salts were triturated and
extracted with CH Cl (75 mL); the combined organic extract
was dried over MgSO , filtered, and concentrated. Recrystal-
×
40 mL); the ethereal solution was washed with aq NaHCO
3
5
4
(
30 mL) and brine (30 mL), dried over MgSO , filtered, and
4
2
2
1
concentrated to give 3.48 g of a mixture of 1-(1′,1′-dichloro-
ethyl)- and 1-(1′-chloroethenyl)-7-phenylbicyclo[4.1.0]heptanes.
The crude mixture of chlorides was dissolved in 50 mL of dry
DMSO and placed in a flask equipped with a reflux condenser.
°
2
2
2
2
2
As NaNH (1.66 g, 38.2 mmol) was added, heat was evolved;
4
the reaction mixture was then stirred at 75 °C for 19 h. It
was then cooled to room temperature and treated with 50 mL
of ice cold brine; the hydrolyzed mixture was extracted with
lization of the crude product from methanol gave benzyl phenyl
sulfoxide (7.72 g, 35.7 mmol, 71.4%) as white crystals, mp 122-
2
2
1
24.5 °C (lit. mp 122-123 °C).
CH
2
Cl
2
(3 × 50 mL), and the organic extract was washed with
S-Ben zyl-S-ph en yl-N-(p-tolylsu lfon yl)su lfoxim ide.15 To
H
2
O (5 × 30 mL), dried over MgSO
4
, filtered, and concentrated
a 100-mL flask were added benzyl phenyl sulfoxide (5.02 g,
to give 1-ethynyl-7-exo-phenylbicyclo[4.1.0]heptane (15), a
single isomer by GC. Column chromatography (silica gel,
pentane) gave the product as a yellow oil (350 mg, 1.8 mmol,
2
3
2
5
1
3.2 mmol), freshly prepared tosyl azide (6.76 g, 34.3 mmol),
0 mL of anhydrous methanol, and 2 µm Cu power (0.99 g,
5.6 mmol; Allied Chemical). The reaction mixture was heated
1
8%). A small sample was further purified by preparative gas
to reflux for 16 h, cooled, and concentrated by rotary evapora-
tion. Saturated aqueous Na EDTA (50 mL) and CH Cl (75
1
chromatography (10% SE-30, 125 °C). H NMR δ 1.24-1.48
2
2
2
(
m, 4 H), 1.70-1.81 (m, 2 H), 1.82 (s, 1 H), 1.98-2.22 (m, 4
mL) were added to the concentrate with stirring, and the
mixture was filtered. The salts were washed with additional
1
3
H), 7.16-7.33 (m, 5 H); C NMR δ 20.0, 20.4, 21.0, 22.7, 26.9,
3
0.6, 35.2, 67.5, 89.5, 125.9, 127.7, 127.9, 138.8; MS m/z (rel
CH
2
Cl
2
(50 mL), and the CH
2
Cl
2
solution was extracted with
SO , filtered, and concen-
+
intensity) 196 (59, M ), 195 (37), 168 (55), 167 (100), 165 (54),
water (2 × 30 mL), dried over Na
2
4
1
3
53 (71), 141 (29), 128 (36), 115 (56), 91 (52), 77 (29), 51 (25),
9 (30). Anal. Calcd for C15 16: C, 91.78; H, 9.15. Found:
trated to give crude product. Recrystallization from ethanol
H
gave S-benzyl-S-phenyl-N-(p-tolylsulfonyl)sulfoximide (3.41 g,
C, 92.00; H, 8.45.
1
5
8
1
7
.84 mmol, 38.1%) as white crystals, 149-151 °C (lit. mp
1
-Eth en yl-7-exo-p h en ylbicyclo[4.1.0]h ep ta n e (1). The
1
48-149 °C). H NMR δ 2.4 (s, 3 H), 4.8 (q, J ) 7.4 Hz, 2 H),
.0 (d, J ) 9.7 Hz, 2 H), 7.25 (m, 6 H), 7.4 (m, 2 H), 7.6 (m, 2
bicyclic alkyne 15 (350 mg, 1.8 mmol) was dissolved in 35 mL
of freshly distilled pentane. Special care was taken to avoid
any contamination of the hydrocarbon solvent with ethereal
impurities. To the stirring solution was added 3.6 mL (3.6
H), 7.9 (d, J ) 8.2, 2 H).
1
-Acetyl-7-p h en ylbicyclo[4.1.0]h ep ta n es (14). A 60%
dispersion of NaH in mineral oil (1.18 g, 29.4 mmol) under
argon was washed with dry pentane (3 × 15 mL). The residual
pentane was removed with a stream of argon. Freshly distilled
DMSO (80 mL) and S-benzyl-S-phenyl-N-(p-tolyl-sulfonyl)-
1
1,14
mmol) of 1.0 M DIBAL in hexanes at room temperature.
The extent of reduction was monitored by GC, and after 100
min 20 mL of H O was added. The hydrolyzed mixture was
2
transferred to a separatory funnel with the aid of additional
pentane; the aqueous layer was separated and extracted with
pentane (3 × 25 mL). The aluminum salts were extracted with
pentane (2 × 25 mL). The combined organic material was
2 5
sulfoximide (8.10 g, 21.0 mmol, dried under vacuum over P O
for 24 h) was added. The mixture was stirred at room
temperature until all hydrogen evolution had ceased (2 h), and
then 1-acetyl-1-cyclohexene (2.32 g, 19.1 mmol) in 15 mL of
dry DMSO was added dropwise. The reaction mixture was
4
dried over MgSO , filtered, and concentrated to give the crude
bicyclic alkene 1. Column chromatography (silica gel, pentane)
gave the product as a clear oil (100 mg, 0.5 mmol, 28%). A
small sample of 1 was further purified by preparative gas
stirred for 19 h at room temperature, and then 40 mL of H
and 40 mL of ether were added. The organic phase was
washed with H , filtered, and
2
O
2
O (4 × 20 mL), dried over MgSO
4
1
chromatography (10% SE-30, 100 °C). H NMR δ 1.23-1.53
concentrated to give a mixture of the bicyclic ketones 14-en d o
and 14-exo in a 1:4 ratio (analytical GC). Column chroma-
tography (silica gel, hexanes:ethyl acetate, 10:1) gave this
mixture of ketones as a clear oil (2.10 g, 9.8 mmol, 51.5%).
(
1
m, 4 H), 1.62 (td, J ) 7.7, 1.5, 1 H), 1.70-1.81 (m, 1 H), 1.87-
.96 (m, 1 H), 1.99-2.18 (m, 3 H), 4.84 (dd, J ) 10.6, 1.5, 1
H), 4.97 (dd, J ) 17.3, 1.5, 1 H), 5.28 (dd, J ) 17.3, 10.6, 1 H),
7
2
.11-7.28 (m, 5 H); 13C NMR δ 21.0, 21.6, 23.3, 24.5, 26.9,
1
-Acetyl-7-exo-ph en ylbicyclo[4.1.0]h eptan e (14-exo) was
9.5, 35.3, 111.0, 125.6, 127.9, 128.8, 139.6, 143.5; MS m/z (rel
purified by preparative gas chromatography (10% SE-30, 125
+
intensity) 198 (23, M ), 183 (17), 169 (31), 155 (54), 141 (85),
1
°
C). H NMR δ 1.29-1.51 (m, 4 H), 1.78 (s, 3 H), 1.84 (t, J )
.8 Hz, 1 H), 1.96-2.09 (m, 1 H), 2.12-2.36 (m, 3 H), 2.43 (td,
1
29 (81), 115 (65), 91 (100), 79 (78), 39 (47). Anal. Calcd for
18: C, 90.85; H, 9.15. Found: C, 90.78; H, 9.21.
-(E-2′-d-Eth en yl)-7-exo-ph en ylbicyclo[4.1.0]h eptan e (E-
-d ). To a sample of the bicyclic alkyne 15 (100 mg, 0.51
6
15
C H
1
1
3
J ) 7.0, 1.6 Hz, 1 H), 7.08-7.24 (m, 5 H); C NMR δ 20.6,
2
2
1
1.6, 22.3, 22.7, 26.4, 28.0, 38.2, 40.6, 126.3, 128.1, 128.3, 137.2,
1
06.5; MS m/z (rel intensity) 214 (21, M+), 199 (15), 171 (31),
mmol) in 10 mL of freshly distilled dry pentane was added
with stirring 1.02 mL (1.02 mmol) of 1.0 M DIBALH in
hexanes at room temperature. The extent of reduction was
29 (55), 115 (23), 91 (58), 43 (100). Anal. Calcd for C15H18O:
C, 84.07; H, 8.47. Found: C, 83.86; H, 8.51.
2
monitored by GC, and after 12 h, 3 mL of D O was added.
(
21) Leonard, N. J .; J ohnson, C. R. J . Org. Chem. 1962, 27, 282-
The mixture was stirred for 4 h and then transferred to a
separatory funnel with the aid of additional pentane. The
biphasic mixture was diluted with brine and extracted. The
organic layer was separated, dried, filtered, and concentrated
to give crude olefin E-1-d . Purification by preparative GC on
2
1
5
84.
(
22) Shriner, R. L.; Struck, H. C.; J orison, W. J . J . Am. Chem. Soc.
930, 52, 2060-2069.
(
954-5956.
23) Doering, W. von E.; Depuy, C. H. J . Am. Chem. Soc. 1953, 75,