advantages of available reagents, excellent regio- and stereo-
selectivity, and the simplicity of a ‘one pot’ procedure which
avoids the preparation of intermediate tellurenyl halides.
3.25 (3H, s), 3.85 (2H, d, J 5), 6.15 (1H, dt, J 17 and 5), 6.95
(1H, d, J 17), 7.02 (2H, d, J 8), 7.60 (2H, d, J 8); MS (EI) m/z
292 (47), 290 (46), 288 (27.8), 261 (13), 259 (12.5), 131 (42.4),
91 (29.2), 71 (100) (Found: C, 45.45; H, 4.91. C11H14OTe
requires C, 45.59; H, 4.87%).
Experimental
3f. Oil. ν (film)/cmϪ1 1575, 940; δH (60 MHz) 1.23 (3H, t, J 7),
3.46 (2H, q, J 7), 3.90 (2H, d, J 5), 6.21 (1H, dt, J 16 and 5), 6.9
(1H, d, J 16), 7.0–7.8 (5H, m); MS (EI) m/z 292 (45), 290 (49),
247 (17.7), 245 (17), 117 (42), 85 (100), 57 (63) (Found: C,
45.71; H, 4.93. C11H14OTe requires C, 45.59; H, 4.87%).
1H NMR spectra were recorded on a PMX-60 and AZ-300
spectrometers, using CDCl3 as the solvent with TMS as an
internal standard; J-values are given in Hz. IR spectra were
determined on a PE-683 spectrophotometer. Mass spectra were
obtained on an HP5989A spectrometer. Mps were measured on
a Büchi 535 melting point apparatus and are uncorrected.
Elemental analyses were conducted using a Yanaco MT-3CHN
elemental analyser. All reactions were carried out in pre-dried
glassware (150 ЊC; 4 h) and cooled under dry nitrogen. Tetra-
hydrofuran (THF) was distilled over sodium benzophenone
ketyl immediately before use.
Acknowledgements
Project 29772007 was supported by the National Nature
Science Foundation of China and this work was also supported
by The Laboratory of Organometallic Chemistry, Chinese
Academy of Science.
General procedure for the synthesis of E-alkenyltellurides
References
To a solution of cyclohexene (10 mmol) in THF (10 cm3) was
added a solution of diborane (5 mmol) in THF at 0 ЊC with
stirring; the precipitate thus formed [(c-Hex)2BH] was stirred
at 0 ЊC for 1 h. The reaction mixture was diluted with a solution
of a terminal acetylene 1 (5 mmol) added at Ϫ10 ЊC, and the
mixture was kept at 0 ЊC for 2 h. After the precipitate 2 had
dissolved, the resulting solution was treated with 3 M NaOH
(2 cm3), diorgano ditelluride (4 mmol), and 3% Pd(PPh3)4, then
was refluxed for 3 h under N2. After the reaction was complete,
normal work-up was performed. Vinyltellurides 3 were isolated
and purified by TLC with petroleum ether (distillation range
30–60 ЊC) as developer.
1 For a review, see: J. V. Comasseto, L. W. Ling, N. Petragnani and
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3a.4 Oil. ν (film)/cmϪ1 1570, 950; δH (300 MHz) 7.20 (1H, d,
J 16.6), 7.39 (8H, m), 7.64 (1H, d, J 16.6), 7.83 (2H, m).
3b. Mp 51–52 ЊC; ν (KBr)/cmϪ1 1574, 956; δH (300 MHz)
2.34 (3H, s), 6.8–7.8 (11H, m); MS (EI) m/z 324 (98.7), 322
(100), 195 (62), 179 (82), 91 (39) (Found: C, 55.87; H, 4.43.
C15H14Te requires C, 55.97; H, 4.38%).
3c.3 Oil. ν (film)/cmϪ1 1570, 930; δH (60 MHz) 0.91 (3H, m,
J 7), 1.1–2.1 (4H, m), 2.80 (2H, t, J 7), 6.98 (1H, d, J 16), 7.30
(5H, m), 7.48 (1H, d, J 16).
3d. Oil. ν (film)/cmϪ1 1580, 950; δH (60 MHz) 3.29 (3H, s),
3.95 (2H, d, J 5), 6.27 (1H, dt, J 16 and 5), 7.1 (1H, d, J 16), 7.2–
7.8 (5H, m); MS (EI) m/z 278 (30.5), 276 (30), 247 (7.5), 245
(6.2), 71 (100) (Found: C, 43.67; H, 4.23. C10H12OTe requires
C, 43.55; H, 4.17%).
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3e. Oil. ν (film)/cmϪ1 1580, 947; δH (60 MHz) 2.31 (3H, s),
Paper 9/03340H
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J. Chem. Soc., Perkin Trans. 1, 1999, 2625–2626