C. Chen et al. / Journal of Fluorine Chemistry 101 (2000) 285±290
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J 20.1 Hz, 1H), 6.90 (m, 2H), 7.06 (m, 3H), 7.44 (t,
J 7.2 Hz, 1H), 7.53 (m, 3H), 7.93 (t, J 9.0 Hz, 2H),
8.08 (m, 1H); 19F NMR (CDCl3) ꢀ: 84.8 (d, J 18.3 Hz);
provide (Z)-6f as a colorless oil (75 mg, 80%). H NMR
(CDCl3) ꢀ: 6.25 (d, J 40.2 Hz, 1H), 6.48 (m, 1H), 6.60±
6.62 (m, 1H), 7.22±7.28 (m, 1H), 7.33±7.39 (m, 2H), 7.44±
7.46 (m, 1H), 7.57±7.61 (m, 2H); 19F NMR (CDCl3) ꢀ:
GCMS (EI): m/e 248 (M ); HRMS for C18H13F (M ),
calcd. 248.1003; found 248.1012.
120.82 (d, J 39.9 Hz); GCMS (EI): m/e 188 (M ) at
tr 4.91 min; HRMS: m/e for C12H9FO [M H ] calcd.
189.0716; found 189.0723.
(Z)-1,4-Diphenyl-2-¯uoro-1-buten-3-yne (Z-6g) Color-
3.3. Palladium catalyzed cross-coupling reaction of 1-
fluorovinyl chloride (E, Z mixture) with arylboronic acids.
1
less oil, 75% yield; H NMR: 6.15 (d, J 35.1 Hz, 1H),
6.48 (m, 1H), 7.25±7.39 (m, 6H), 7.50±7.57 (m, 4H); 19F
(E)- and (Z)-1-¯uoro-1-(4-methoxyphenyl)-2-pheny-
lethene (7) A mixture of (E, Z)-1-chloro-1-¯uoro-2-(4-
methoxyphenyl)ethene (E/Z 44 : 56, 93 mg, 0.5 mmol),
phenylboronic acid (74 mg, 0.6 mmol), potassium carbo-
nate (210 mg, 1.5 mmol) in benzene (8 ml), ethanol (1.5 ml)
and water (1.5 ml) was treated with tetrakis(triphenylpho-
sphine)palladium(0) (30 mg, 0.025 mmol) under nitrogen
and heated at re¯ux for 8 h. This mixture was diluted with
ethyl acetate (100 ml), dried over MgSO4, ®ltrated and
concentrated in vacuo. GC-MS analysis of the crude pro-
ducts showed a mixture of (E)- and (Z)-7 with a ratio of
47 : 53 (Z/E). Attempts to separate these two isomers on
silica gel failed, and the product was obtained, after chro-
matography, as a colorless oil (80% yield). 1H NMR
(CDCl3) ꢀ: (Z-7) 3.82 (s, 3H), 6.26 (d, J 40.2 Hz, 1H),
6.91 (d, J 9.0 Hz, 2H), 6.30±6.46 (m, 3H), 7.60 (m, 4H);
(E-7) 3.77 (s, 3H), 6.40 (d, J 21.9 Hz, 1H), 6.76 (d,
J 8.7 Hz, 2H), 7.08 (d, J 8.7 Hz, 2H), 6.30±6.46 (m,
NMR (CDCl3) ꢀ: 100.63 (d, J 35.0 Hz); GCMS: m/e
222 (M ) at tr 6.31 min; HRMS: m/e for C16H11F
[M H ] calcd. 223.0923; found 223.0931.
(Z)-1-Fluoro-1-(2-thienyl)-2-phenylethene (Z-6h) Color-
1
less oil, 78% yield; H NMR: 6.15 (d, J 39.3 Hz, 1H),
7.03±7.07 (m, 1H), 7.22±7.39 (m, 5H), 7.57±7.61 (m, 2H);
19F NMR: 104.19 (d, J 38.8 Hz); GCMS: m/e 204 (M )
at tr 5.65 min; HRMS: m/e for C12H9FS [M H ] calcd.
205.0487; found 205.0494.
(Z)-2-Fluoro-3-ethoxy-1-phenyl-1,3-butadiene (11) Col-
orless oil, 9% yield: 1H NMR: (CDCl3) ꢀ: 1.41 (t,
J 7.0 Hz, 3H), 3.89 (q, J 7.0 Hz, 2H), 4.32 (m, 1H),
4.74 (dd, J 39.5 Hz, 1H), 6.23 (m, 1H), 7.25±7.42 (m,
3H), 7.53±7.59 (m, 2H); 19F NMR (CDCl3) ꢀ: -120.04 (d,
J 39.2 Hz); GCMS: m/e 192 (M ).
3.5. Palladium catalyzed cross-coupling reaction of (Z)-b-
bromo-b-fluorostyrene with organostannanes.
5H); 19F NMR (CDCl3) ꢀ:
117.7 (Z-isomer, d,
J 39.8 Hz);
98.6 (E-isomer, d, J 21.5 Hz); MS
(E)-1-Fluoro-1,2-diphenylethene (E-6a) A solution of
(Z)-1-bromo-1-¯uoro-2-phenylethene (100 mg, 0.5 mmol),
tributylphenyltin (240 mg, 0.65 mmol) in dioxane was trea-
ted with tetrakis(triphenylphosphine)palladium(0) (30 mg,
0.025 mmol) under nitrogen and heated at re¯ux for 16 h.
Chromatography of the reaction mixture on silica gel with
hexanes gave E-6a in 94% isolated yield.
(EI): m/e 228 (M ); HRMS for C15H13FO (M ), calcd.
228.0950; found 228.0970.
(E)-1-Fluoro-1,4-diphenylbutene and (Z)-1-Fluoro-1,4-
diphenylbutene (8) GC-MS analysis of the crude products
shown a mixture of Z/E 45 : 55. The two isomers were
1
not separated by silica gel. Colorless oil, 83% yield; H
NMR (CDCl3) ꢀ: (Z-isomer) 2.60 (m, 2H), 2.78 (m, 2H),
5.48 (dt, J 37.2, 7.5 Hz, 1H), 7.15±7.50 (m,10H); 19F
NMR (CDCl3) ꢀ: 120.5 (Z-isomer, d, J 36.7 Hz);
(E)-1-Fluoro-1-(2-furfuryl)-2-phenylethene (E-6f) Color-
less oil, 81% yield; 1H NMR (CDCl3) ꢀ: 6.40 (m, 1H), 6.41
(d, J 24.0 Hz, 1H), 7.23 (m, 1H), 7.51 (m, 5H); GCMS
101.74 (d, J 23.0 Hz); MS (EI): m/e 226 (M );
(EI): m/e188 (M ).
HRMS for C16H15F (M ): calcd. 226.1258; found
226.1263.
(Z)-3-Fluoro-4-phenyl-3-buten-2-one (12) A mixture of
(E)-b-bromo-b-¯uorostyrene (100 mg, 0.50 mmol), 1-(tri-
butylstannyl)vinyl ethyl ether (10) (200 mg, 0.55 mmol),
tetrakis(triphenylphosphine)palladium(0) (32 mg, 0.025,
5 mol%) in dioxane (5 ml) was re¯uxed under nitrogen
overnight. The 19F NMR was performed on a sample of
the reaction mixture to determine yield (95%, D2O insert for
signal lock-on; C6F6 as external standard). The reaction
mixture was concentrated in vacuo, dissolved in ether,
washed with KF solution and brine. The ether was
concentrated, puri®ed by preparative TLC plates to provide
Z-12 [20] in 14% yield. 1H NMR: 2.42 (d, J 1.8 Hz, 3H),
6.63 (d, J 36.6 Hz, 1H), 7.38±7.44 (m, 3H), 7.64±7.72
3.4. Palladium catalyzed cross-coupling reaction of (E)-b-
bromo-b-fluorostyrene with organostannanes.
(Z) 1-Fluoro-1-(2-furanyl)-2-phenylethene (Z-6f) A mix-
ture of (E)-1-¯uoro-1-bromo2-phenylethene (100 mg,
0.50 mmol), 2-(tributylstannyl)furan (195 mg, 0.55 mmol),
tetrakis(triphenylphosphine)palladium(0) (32 mg, 0.025,
5 mol%) in dioxane (5 ml) was re¯uxed under nitrogen
overnight. The 19F NMR was performed on a sample of
the reaction mixture to determine yield (97%, D2O insert for
signal lock-on; C6F6 as external standard). The reaction
mixture was concentrated in vacuo and puri®ed by ¯ash
chromatography on silica gel (eluted with hexane, Rf0.5) to
(m, 2H); GCMS: m/e 164 (M ) at tr 4.31 min; HRMS:
m/e for C16H11F [M H ] calcd. 165.0716; found
165.0722.