J. Liu et al.
(–CH3). MS (ESI) m/z: calcd for [C33H44FeO5] 576.25; found (M + H)+
added V2O5 (0.01 mmol) dissolved in 30% H2O2 (1mmol) in an
ice bath for 10 h. This was then extracted with dichloromethane
and dried. After removal of solvent, the residue was subjected to
chromatography (10:90 ethyl acetate–petroleum ether) to afford
5a (0.12 g, 0.21 mmol, 21%) as an orange solid.
577.3, (M + Na)+ 599.3. M.p. 58.7-61.9°C
Synthesis of ethyl 3-(5-(16-ferrocene-16-oxohexadenoyl)furan-2-yl)propanoate
(4a)
Sulfoxide chloride (45 ml, 618 mol) was added dropwise to
hexadecanedioic acid (8.5g, 29.7mmol) and heated at 85 °C for
12 h. Sulfoxide chloride was removed in vacuum, and then 1,16-
hexadecanedioyl dichloride was obtained without further purifica-
tion. Ferrocene (5.53g, 29.7mmol) and 3-(furan-2-yl)propanoate
(5g, 29.7 mmol) were stirred well in dichloromethane (150ml).
The reaction flask was charged with 1,16-hexadecanedioyl
dichloride in dichloromethane (150 ml) and the stirred mixture
was added slowly in an ice bath. Anhydrous aluminium chloride
(7.92g, 59.4mmol) was added to this solution carefully over
30 min. After most of the solvent was removed under vacuum,
the crude mixture was diluted with hydrochloric acid (30 ml,
1 mol lꢀ1) and extracted with dichloromethane (3× 25 ml), then
dried over anhydrous Na2SO4. When the solvent was evaporated,
the residue was subjected to chromatography (10:90 ethyl
acetate–petroleum ether) to afford 4a (0.92g, 1.5 mmol, 5.12%) as
an orange solid.
Elemental analysis; found (%): C, 68.36; H, 7.97. Calculated for
C32H42FeO5 (%): C, 68.05; H, 7.51. 1H NMR (400 MHz, CDCl3, δ, ppm):
7.98 (d, J= 3.4 Hz, 1H, –O–C1¼C2–H), 6.90 (d, J= 3.4 Hz, 1H, –O–
C4¼C3–H), 4.79 (s, 2H, –Fe–Cp–H(α)), 4.50 (s, 2H, –Fe–Cp–H(β)), 4.20
(s, 5H, Cp–H), 3.88 (s, 3H, –COOCH3), 2.69 (t, J= 7.3 Hz, 2H, –C¼O–
CH2–), 1.79 (t, J= 6.7Hz, 2H, –C¼O–CH2–), 1.68–1.70 (m, 2H, –C¼O–
CH2–CH2–), 1.44–1.46 (m, 2H, –C¼O–CH2–CH2–), 1.26–1.33 (m, 20H,
–CH2–). 13C NMR (100 MHz, CDCl3, δ, ppm): 203.64 (–Fe–Cp–C¼O),
192.23 (–furan–C¼O), 172.32 (–COO–), 153.48 (–O–C1¼C2–H),
141.39 (–O–C4¼C3–H), 131.05 (–O–C1¼C2–H), 124.95 (–O–C4¼C3–
H), 78.23 (–Fe–C–C¼O), 71.08 (–Fe–Cp(α)), 68.72 (–Fe–Cp(β)), 68.33
(–Cp), 50.61 (–COO–CH3), 38.73 (–C¼O–CH2–), 37.97 (–C¼O–CH2–)
31.94 (–CH2–), 28.77 (–CH2–), 28.50 (–CH2–), 28.42 (–CH2–), 28.35 (–
CH2–), 28.31 (–CH2–), 25.33 (–CH2–), 23.90 (–CH2–), 23.60 (–CH2–).
MS (ESI) m/z: calcd for [C32H42FeO5] 564.76; found (M + H)+ 565.87.
Synthesis of tricarbonyl (3-(5-(10-cyclopentadienyl-10-oxodecanoyl)furan-2-yl)
propanoic acid) rhenium (CpTRe-10-oxo-FPA, 1b)
Elemental analysis; found (%): C, 68.48; H, 7.95. Calculated for
C35H48FeO5 (%): C, 69.53; H, 8.00. 1H NMR (400 MHz,CDCl3, δ,
ppm): 7.08 (d, J = 3.4 Hz, 1H, –O–C1¼C2–H), 6.20 (d, J = 3.4Hz, 1H,
–O–C4¼C3–H), 4.79 (s, 2H, –Fe–Cp–H(α)), 4.50 (s, 2H, –Fe–Cp–H(β)),
4.21 (s, 5H, Cp–H), 4.16 (q, J = 7.1Hz, 2H, –O–CH2–CH3), 3.04 (t, J =
7.4 Hz, 2H, –C¼O–CH2–), 2.67–2.76 (m, 6H, –C¼O–CH2–), 1.66–1.71
(m, 4H, –C¼O–CH2–CH2–), 1.23–1.34 (m, 23H, –CH2–, –CH3). 13C
NMR (100 MHz, CDCl3, δ, ppm): 204.78 (–Fe–Cp–C¼O), 189.27 (–fu-
ran–C¼O), 171.95 (–COO–), 159.21 (–O–C1¼C2–H), 151.75 (–O–
C4¼C3–H), 118.44 (–O–C1¼C2–H), 108.48 (–O–C4¼C3–H), 79.29
(–Fe–C–C¼O), 72.07 (–Fe–Cp(α)), 69.71 (–Fe–Cp(β)), 69.32 (–Cp),
60.72 (–O–CH2–), 39.80 (–C¼O–CH2–), 38.29, (–C¼O–CH2–) 32.13
(–CH2–), 29.62 (–CH2–), 29.59 (–CH2–), 29.56 (–CH2–), 29.52
(–CH2–), 29.47 (–CH2–), 29.40 (–CH2–), 29.35 (–CH2–), 24.63 (–fu-
ran–CH2–CH2–C¼O–), 24.60 (–furan–CH2–CH2–C¼O–), 23.73 (–
C¼O–CH2–), 14.19 (–CH3). MS (ESI) m/z: calcd for [C35H48FeO5]
604.29; found M+ 605.1, (M + H)+ 606.2. M.p. 62.7–66.3 °C.
Ester 1a (100 mg), NH4ReO4 (30 mg, 0.11 mmol), Cr(CO)6 (128 mg,
0.58 mmol) and CrCl3 (30mg, 0.19 mmol) with dry methanol
(0.8ml) were placed in
a high-pressure tank of poly-
tetrafluoroethylene, then heated at 180°C. After 3 h the mixture
was cooled for 30min in an ice bath. The residue was dissolved
in CH2Cl2, passed through a 0.2μm Millipore filter, and the sol-
vent was removed under vacuum. The residue was added to
3 ml of 0.3M NaOH and methanol (10 ml) and heated at 80 °C
for 40min. Methanol was removed under reduced pressure at
40°C, and the solution was acidified to pH = 7 with 0.1M HCl.
The reaction mixture was extracted with dichloromethane, and
the organic layer was dried over anhydrous Na2SO4 then concen-
trated. The crude products were purified by flash column chro-
matography (10:20 ethyl acetate–petroleum ether with 1%
acetic acid) to afford 1b (10.0 mg, 15.6 nmol, 8.2%) as a gray
solid.
Elemental analysis; found (%): C, 47.68; H, 4.47. Calculated for
Synthesis of methyl 5-(16-ferrocene-16-oxohexadenoyl)furan-2-carboxylate
(5a)
C25H ReO8 (%): C, 46.79; H, 4.24. 1H NMR (400 MHz, CDCl3, δ,
185
27
ppm): 7.08 (d, J= 3.4Hz, 1H, –O–C1¼C2–H), 6.02 (d, J= 3.4 Hz, 1H, –
A stirred mixture of 2-furaldehyde (5.71 g, 59.2mmol), ethylene
glycol (3.68 g, 59.4 mmol) and p-TsOH (1mol%) in toluene
(350 ml) was refluxed for 5 h with azeotropic removal of water;
the solvent was removed under vacuum. Sulfoxide chloride
(45 ml, 618mol) was added dropwise to hexadecanedioic acid
(8.5 g, 29.7mmol) and heated at 85 °C for 12 h. Sulfoxide chloride
was removed in vacuum, and then 1,16-hexadecanedioyl
dichloride was obtained without further purification. Ferrocene
(5.53g, 29.7mmol) was added to the mixture and stirred well in
dichloromethane (150 ml). The reaction flask was charged with
1,16-hexadecanedioyl dichloride in dichloromethane (150 ml)
and the stirred mixture was added slowly in an ice bath. Anhy-
drous aluminium chloride (7.92 g, 59.4mmol) was added to this
solution carefully over 30min. After most of the solvent was re-
moved under vacuum, the crude mixture was diluted with hydro-
chloric acid (30 ml, 1 mol lꢀ1) and extracted with dichloromethane
(3× 25 ml), then dried over anhydrous Na2SO4. When the solvent
was evaporated, the residue was subjected to chromatography
(10:90 ethyl acetate–petroleum ether) to afford 5. Compound 5
(0.56g, 1 mmol) was dissolved in methanol (5ml) to which was
O–C4¼C3–H), 5.99 (t, J= 2.3 Hz, 2H, –Re–Cp–H(α)), 5.39 (t, J=2.3Hz,
2H, –Re–Cp–H(β)), 3.06 (t, J= 7.4 Hz, 2H, –C¼O–CH2–), 2.73–2.79 (m,
4H), 2.58 (t, J= 7.2 Hz, 2H, –C¼O–CH2–), 1.67–1.69 (m, 4H, –C¼O–
CH2–CH2–), 1.33 (s, 8H, –CH2–); 13C NMR (100 MHz, CDCl3, δ, ppm):
194.44 (–Re–C¼O), 190.84 (–Re–C¼O), 188.39 (–furan–C¼O), 176.16
(–COO–), 157.81 (–O–C1¼C2–H), 150.79 (–O–C4¼C3–H), 117.56 (–O–
C1¼C2–H), 107.65 (–O–C4¼C3–H), 95.15 (–Re–C–C¼O), 86.92 (–Re–
Cp(α)), 84.16 (–Re–Cp(β)), 37.78 (–C¼O–CH2–), 37.22 (–C¼O–CH2–),
30.76 (–CH2–), 28.17 (–CH2–), 28.10 (–CH2–), 27.94 (–CH2–), 23.50 (–
CH2–), 22.44 (–furan–CH2–CH2–C¼O–), 23.34 (–furan–CH2–CH2–
C¼O–). MS (ESI) m/z: calcd for [C25H ReO8] 640.52; found (M + H+,
185
27
185 Re) 640.8, (M + H+, 187 Re) 642.8.
Synthesis of tricarbonyl (3-(5-(12-cyclopentadineyl-12-oxododecanoyl)furan-2-
yl)propanoic acid) rhenium (CpTRe-12-oxo-FPA, 2b)
Prepared analogously as described above, compound 2b as a gray
solid was obtained from 1b (13 mg, 19.4 nmol, 10.22%).
Elemental analysis; found (%): C, 47.78; H, 4.62. Calculated for
185
C27H ReO8 (%): C, 48.42; H, 4.67. 1H NMR (400 MHz,CDCl3, δ,
31
ppm): 7.08 (d, J = 3.4Hz, 1H, –O–C1¼C2–H), 6.02 (d, J = 3.4Hz, 1H,
wileyonlinelibrary.com/journal/aoc
Copyright © 2016 John Wiley & Sons, Ltd. Appl. Organometal. Chem. 2016, 30, 596–604