7
684 J . Org. Chem., Vol. 65, No. 22, 2000
Notes
which then reacted with (PhSe)
process to give the three-component coupling product (8d )
2
and 7a via the radical
Gen er a l P r oced u r e for th e Th r ee-Com p on en t Cou p lin g
of Alk yn es, Vin ylcyclop r op a n es, a n d Dip h en yl Dise-
len id e: Eth yl 2-[(P h en ylselen o)m eth ylen yl]-4-p h en yl-7-
(
(
entry 3). The reaction of 3e with 7a in the absence of
PhSe) in the dark gave rise to 3f in high yield (eq 4).
(
)
p h en ylselen o)-4-h ep ten oa te (8b). In a Pyrex glass tube (φ
5 mm, length ) 18 cm) under argon atmosphere were placed
2
This suggests that the formation of 3f may proceed via
ionic process.
ethyl propiolate (0.6 mmol, 58.9 mg), 1-cyclopropylstyrene (2.4
mmol, 346.1 mg), and diphenyl diselenide (0.2 mmol, 62.4 mg).
The mixture was irradiated with a tungsten lamp (500 W) at
4
0 °C for 14 h. Additionally, diphenyl diselenide (0.2 mmol, 62.4
mg) was added two times to the mixture, when the yellow color
of the mixture turned pale yellow. After the reaction was
complete, unreacted materials were evaporated, and the puri-
fication of the products was performed on a recycling prepara-
tive HPLC (J apan Analytical Industry Co. Ltd., Model LC-908),
equipped with J AIGEL-1H and -2H columns (GPC) using
The three-component coupling of cyclopropyl-substi-
tuted enol silyl ether (7b) with ethyl propiolate (3a ) and
PhSe) afforded the desired 1,7-bis(phenylseleno)-2-
2
ethoxycarbonyl-4-(tert-butyldimethylsiloxy)-1,4-hepatdi-
ene (8e) in good yield (entry 4). On the other hand, the
three-component coupling of ethoxycarbonyl-substituted
vinylcyclopropane (7c) gave a mixture of the desired
CHCl
ylseleno)methylenyl]-4-phenyl-7-(phenylseleno)-4-heptenoate
8b) obtained as a stereoisomeric mixture (4E/4Z ) 82/18): a
3
as an eluent, yielding 239.5 mg (72%) of ethyl 2-[(phen-
(
(
1
3
pale yellow oil; H NMR (600 MHz, CDCl ): (4E)-isomer: δ 1.35
(
J ) 7.3 Hz, 2 H), 3.48 (s, 2 H), 4.28 (q, J ) 7.2 Hz, 2 H), 5.87
(t, J ) 7.3 Hz, 1 H), 7.20-7.30 (m, 14 H), 7.44-7.46 (m, 2 H).
t, J ) 7.2 Hz, 3 H), 2.57 (q like, J ) 7.3 Hz, 2 H), 2.95 (t,
(
4Z)-isomer: δ 1.32 (t, J ) 7.2 Hz, 3 H), 2.39 (q like, J ) 7.3
2
coupling product (8f) and the (PhSe) -adducts of 3a (6a )
Hz, 2 H), 2.89 (t, J ) 7.3 Hz, 2 H), 3.48 (s, 2 H), 4.25 (q, J ) 7.2
Hz, 2 H), 5.60 (t, J ) 7.3 Hz, 1 H), 7.20-7.30 (m, 14 H), 7.44-
7
and 7c (11), as illustrated in eq 5.
.46 (m, 2 H). The stereochemistry of the products were
1
3
determined by NOE experiments: C NMR (100 MHz, CDCl
3
):
(4E)-isomer: δ 14.3, 27,0, 29.3, 32.9, 60.9, 125.0, 126.1, 126.7,
1
1
6
1
1
26.9, 127.5, 128.2, 128.9, 129.0, 129.9, 132.4, 132.5, 133.4,
37.2, 141.9, 143.8, 167.1. (4Z)-isomer: δ 14.1, 27.4, 30.0, 32.9,
0.7, 125.0, 126.2, 126.6, 126.7, 127.4, 127.7, 128.1, 128.8, 129.3,
30.3, 132.9, 133.0, 140.7, 142.1, 143.8, 167.1; IR (NaCl) 3055,
-
1
+
688, 1578, 758, 737, 692 cm ; MS (EI), m/z ) 556 (M , 13.6);
Se : 556.0419, found: 556.0415; Anal.
: C, 60.66; H, 5.09. Found: C, 60.85; H,
HRMS calcd for C28
Calcd for C28 Se
.16.
,7-B is (p h e n y ls e le n o )-2,4-d ip h e n y l-1,4-h e p t a d ie n e
8a ): a pale yellow oil (obtained as a stereoisomeric mixture (4E/
H
28
O
2
2
H
28
O
2
2
5
1
(
1
We already reported that the attempted three-compo-
nent coupling of ethyl propiolate with 1-hexyne using
3
4Z ) 93/7)); H NMR (400 MHz, CDCl ): (4E)-isomer: δ 2.52 (q
like, J ) 7.3 Hz, 2 H), 2.85 (t, J ) 7.3 Hz, 2 H), 3.59 (s, 2 H),
1
3
5
.88 (t, J ) 7.3 Hz, 1 H), 6.36 (s, 1 H), 7.15-7.48 (m, 20 H);
C
(
PhTe)
only the (PhTe)
carbon radical capturing ability of (PhTe)
2
instead of (PhSe)
2
resulted in the formation of
5
3
NMR (100 MHz, CDCl ): (4E)-isomer: δ 26.9, 29.7, 39.6, 118.9,
2
-adduct to 1-hexyne, due to the excessive
1
1
26.4, 126.5, 126.8, 127.0, 127.5, 127.6, 128.3, 129.0, 129.1, 129.1,
29.9, 130.1, 131.2, 132.0, 132.7, 137.3, 141.2, 141.3, 142.3; IR
4
a
2
.
In the case
of 1-cyclopropylstyrene (7a ), however, the corresponding
three-component coupling product (12b) was obtained in
-1
(NaCl) 3054, 3020, 2925, 1578, 999, 805, 759, 736, 691, 670 cm
;
:
+
MS (EI), m/z ) 560 (M , 36.8); HRMS calcd for C31H28Se
2
560.0521, found: 560.0510. Anal. Calcd for C31
H, 5.05. Found: C, 66.62; H, 5.14.
3
(
2% yield together with 44% of the (PhTe)
entry 5).
In conclusion, a novel, three-component coupling of
2
-adduct to 3a 13
2
H28Se : C, 66.67;
1
,7-Bis(p h en ylselen o)-2-m et h ylca r b on yl-4-p h en yl-1,4-
h ep ta d ien e (8c): a pale yellow oil (obtained as a stereoisomeric
): (4E)-
alkynes, vinylcyclopropanes, and diphenyl diselenide (or
ditelluride) under visible-light irradiation has been de-
veloped. The fast rearrangement process of cyclopropyl-
carbinyl radical intermediates contributes to the ef-
ficiency in the desired three-component coupling reaction,
providing the corresponding ring-opened products. We
are currently examining applicability of this methodology
to a variety of different classes of substrates.
mixture (4E/4Z ) 94/6)); 1H NMR (400 MHz, CDCl
3
isomer: δ 2.28 (s, 3 H), 2.53 (q like, J ) 7.3 Hz, 2 H), 2.93 (t, J
) 7.3 Hz, 2 H), 3.50 (s, 2 H), 5.90 (t, J ) 7.3 Hz, 1 H), 7.39 (s,
1 H), 7.15-7.47 (m, 15 H); 13C NMR (100 MHz, CDCl
): (4E)-
3
isomer: δ 26.8, 27.5, 29.4, 34.3, 126.1, 126.9, 127.2, 127.6, 128.4,
29.0, 130.1, 130.9, 132.3, 132.6, 135.0, 137.1, 141.8, 145.4, 198.0;
1
-
1
IR (NaCl) 3055, 1652, 1578, 1531, 739, 692, 669 cm ; MS (EI),
+
m/z ) 526 (M , 16.6); HRMS calcd for C27
found: 526.0327. Anal. Calcd for C27
Found: C, 61.77; H, 5.03.
H
26OSe
2
: 526.0313,
H26OSe : C, 61.84; H, 5.00.
2
4
-P h en yl-3-p en t en yl 2-[(P h en ylselen o)m et h ylen yl]-4-
Exp er im en ta l Section
p h en yl-7-(p h en ylselen o)-4-h ep ten oa te (8d ): a pale yellow
oil (obtained as a stereoisomeric mixture (the ratio was 82/9/6/
3); the major isomer bears (E)-structure concerning the unsatur-
ated bond at 4-position and (Z)-structure concerning the (phen-
Gen er a l Com m en ts.14 Unless otherwise noted, alkynes were
used commercially and were purified by distillation. Vinylcy-
1
5
clopropanes were synthesized according to the literature.
Diphenyl diselenide16 and diphenyl ditelluride were prepared
17
ylseleno)methylenyl group); 1H NMR (400 MHz, CDCl
3
): the
major isomer: δ 2.08 (s, 3 H), 2.55 (q like, J ) 7.3 Hz, 2 H), 2.63
q like, J ) 6.8 Hz, 2 H), 2.93 (t, J ) 7.3 Hz, 2 H), 3.48 (s, 2 H),
.33 (t, J ) 6.8 Hz, 2 H), 5.79 (t, J ) 6.8 Hz, 1 H), 5.87 (t, J )
according to the literature and were recrystallized from hexane.
(
4
(
13) (a) Ogawa, A.; Yokoyama, K.; Yokoyama, H.; Obayashi, R.;
Kambe, N.; Sonoda, N. J . Chem. Soc., Chem. Commun. 1991, 1748.
b) Ogawa, A.; Yokoyama, K.; Obayashi, R.; Han, L.-B.; Kambe, N.;
Sonoda, N. Tetrahedron 1993, 49, 1177.
14) Ogawa, A.; Tanaka, H.; Yokoyama, H.; Obayashi, R.; Yokoyama,
K.; Sonoda, N. J . Org. Chem. 1992, 57, 111.
15) Teragi, T. J . Chem. Soc., C 1971, 3252.
16) Reich, H. J .; Renga, J . M.; Reich, I. L. J . Am. Chem. Soc. 1975,
7, 5434.
17) Haller, W. S.; Irgolic, K. J . J . Organomet. Chem. 1972, 38, 97.
1
3
7.3 Hz, 1 H), 7.20-7.54 (m, 21 H); C NMR (100 MHz, CDCl
the major isomer: δ 16.1, 27.1, 28.4, 29.4, 33.0, 64.3, 122.9, 125.0,
25.7, 126.2, 126.8, 126.9, 127.1, 127.7, 128.2, 128.3, 129.0, 129.2,
30.2, 132.6, 132.7, 133.5, 137.2, 137.7, 142.0, 143.5, 144.3, 167.3;
IR (NaCl) 3054, 2952, 1694, 1577, 758, 737, 692 cm ; MS (EI),
m/z ) 672 (M , 3.96); HRMS calcd for C37
found: 672.1048. Anal. Calcd for C37
Found: C, 65.98; H, 5.41.
3
):
(
1
1
(
-
1
(
(
+
H
36
O
2
Se
2
: 672.1045,
9
36 2 2
H O Se : C, 66.27; H, 5.41.
(