J. CHEM. RESEARCH (S), 1997 299
mined by a Finigan 8230 mass spectrometer. IR spectra were
obtained in heat capillary cells on a Shimadzu IR-408 spectro-
meter. Elemental analyses were conducted using a Perkin-Elmer
240B elemental analyser. Silica gel 50 GF254 was used for analytical
and preparative TLC. Silica gel columns were prepared using silica
gel Q/BKUS 3–91 (100–200 Å mesh). The reactions were carried
out under a stream of dry nitrogen. All solvents were dried, de-
oxygenated and redistilled before use.
General Procedure for the Synthesis of (E)- or (Z)-1-Alkylselanyl-
2-alkylethenes 1 or 2.sTo a stirred mixture of the haloalkylselanyl-
ethene (2 mmol) and Pd(PPh3)4 (0.06 mmol, 3 mol%) at ꢀ78 °C in
THF (10 ml), the organozinc reagent (2 mmol) in THF (5 ml) was
slowly added and the resulting mixture stirred for 1 h. The reaction
temperature was warmed to ꢀ30 °C and then stirred for a further
3 h, followed by stirring for 9 h at room temperature. The reaction
was then quenched by pouring the mixture in to saturated aqueous
NH4Cl (10 ml) in a separatory funnel. Extraction with pentane
(2Å10 ml), washing the combined extracts with saturated aqueous
NH4Cl (10 ml), drying with anhydrous MgSO4 followed by filtra-
tion, concentration in vacuo and flash chromatography (silica gel,
light petroleum (bp 60–90 °C)–EtOAc, 98:2) yielded the pure
product 1 or 2 as an oil. (E)-4-Ethylselanyl-1-phenylbut-3-en-1-yne
1a. dH (CDCl3) 7.05–7.56 (5 H, m), 6.97 (1 H, d, J 16 Hz), 6.35 (1 H,
J 7.9 Hz). vmax/cmꢀ1 1631, 1591, 1552 and 695. m/z 212 (Mǹ ǹ1,
12), 211 (Mǹ, 10), 183 (55) and 104 (100). (Found: Mǹ, 211.1691,
C10H12Se requires Mr, 211.1648). (Z)-1-Methylselanylpenta-
1,4-diene 2b. dH (CDCl3) 6.69 (1 H, d, J 9.7 Hz), 6.18 (1 H, dt, J 9.7,
7.1 Hz), 5.75 (1 H, m), 5.0 (2 H, m), 3.05 (2 H, m), and 2.21 (3 H,
s). vmax/cmꢀ1 1607 and 693. (Found: Mǹ, 161.1017. C6H10Se
requires Mr, 161.1050). (Z)-4-Ethylselanyl-1-trimethylsilylbut-
3-en-1-yne 2c. dH (CDCl3) 6.71 (1 H, d, J 9.5 Hz), 6.06 (1 H, d, J 9.5
Hz), 2.78 (2 H, q, J 7.7 Hz), 1.70 (3 H, t, J 7.7 Hz), 0.31 (9 H, s). vmax/
cmꢀ1 2209, 1618 and 705. (Found: Mǹ, 231.2683. C9H16SiSe
requires Mr, 231.2714). (Z)-3-Ethoxy-1-methylselanylbuta-1,3-diene
2d. dH (CDCl3) 6.41 (1 H, d, J 9.5 Hz), 5.81 (1 H, d, J 9.5 Hz), 4.6
(2 H, s), 3.41 (2 H, q, J 6.5 Hz), 2.20 (3 H, s), 1.25 (3 H, t, J 6.5 Hz).
v
max/cmꢀ1 1611, 910 and 707. (Found: Mǹ, 191.1279, C7H12OSe
requires Mr 191.1312).
We thank the National Natural Science Foundation of
China.
Received, 22nd April 1997; Accepted, 30th April 1997
Paper E/7/02748F
d, J 16 Hz), 2.75 (2 H, q, J 7.7 Hz) and 1.74 (3 H, t, J 7.7 Hz). vmax
/
cmꢀ1 2230, 1615, 1594, 1560, 1548 and 955. m/z 236 (Mǹ ǹ1, 14),
235 (Mǹ, 13), 207 (67) and 127 (100). (Found: Mǹ, 235.1833.
C12H12Se requires Mr 235.1868). (E)-1-Pentylselanyloct-1-ene-3-yne
1c. dH (CDCl3) 6.69 (1 H, d, J 15 Hz), 6.07 (1 H, d, J 15 Hz), 2.77
(2 H, t, J 7.5 Hz), 2.44 (2 H, t, J 5.8 Hz), 1.68 (2 H, m), 1.05–1.60
(8 H, m), 0.91 (3 H, t, J 6.5 Hz) and 0.77 (3 H, t, J 6.3 Hz). vmax/cmꢀ1
2217, 1624 and 945. (Found: Mǹ, 255 and 1149. C13H20Se requires
Mr 255.1188). (E)-4-Pentylselanyl-1-trimethylsilylbut-3-en-1-yne 1d.
References
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d
H (CDCl3) 6.78 (1 H, d, J 15 Hz), 6.14 (1 H, d, J 15 Hz), 2.75 (2 H,
t, J 7.5 Hz), 1.65 (2 H, m), 1.10–1.49 (4 H, m), 0.93 (3 H, t, J 6.6 Hz)
and 0.31 (9 H, s). vmax/cmꢀ1 2205, 1613 and 949. (Found: Mǹ,
273.3551. C12H22SiSe requires Mr, 273.3518). (E)-3-Ethoxy-1-ethyl-
selanylbuta-1,3-diene 1e. dH (CDCl3) 6.37 (1 H, d, J 14.5 Hz), 5.75
(1 H, d, J 14.5 Hz), 4.85 (2 H, s), 3.36 (2 H, q, J 6.7 Hz), 2.21 (3 H,
s) and 1.23 (3 H, t, J 6.7 Hz). vmax/cmꢀ1 1607, 941 and 901. (Found:
M+, 191,1282. C7H12OSe requires Mr 191.1312). (Z)-1-Ethylselanyl-
2-phenylethene 2a. dH (CDCl3) 7.0–7.6 (5 H, m), 6.75 (1 H, d, J 10
Hz), 6.24 (1 H, d, J 10 Hz), 2.95 (2 H, q, J 7.9 Hz) and 1.71 (3 H, t,
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7 E. N. Deryagina, M. G. Voronkov and N. A. Korchevin, Russ.
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