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S.-J. Jong et al. / Journal of Organometallic Chemistry 590 (1999) 42–45
3. Experimental
3.1. General methods
elution with EtOAc. Further purification by silica gel
column (3:97 EtOAc–hexane) afforded 4a (140 mg,
70%).
Melting points are uncorrected. Chemical shifts are
reported relative to CHCl3 [lH 7.26, lC (central line of
t) 77.0]. All reactions requiring anhydrous conditions
were conducted in flame-dried apparatus under an at-
mosphere of nitrogen. Syringes and needles for the
transfer of reagents were dried at 120°C and allowed to
cool in a desiccator over P2O5 before use. THF was
distilled from sodium benzophenone ketyl.
3.3.1. Methylferrocene [6f], 4a
13C-NMR (CDCl3, 50 MHz) l 14.8, 67.1 (2 C), 68.5
(5 C), 69.1 (2 C), 83.9. Anal. Calc. for C11H12Fe: C,
66.04; H, 6.05. Found: C, 65.85; H, 6.12.
3.3.2. Ethylferrocene [6f], 4b
According to the representative procedure (Section
3.3), acetylferrocene (228 mg, 1 mmol) was treated with
SmI2 in refluxing THF for 48 h to give 4b (182 mg,
85%) after chromatography on a silica gel column (3:97
EtOAc–hexane).
3.2. Representati6e procedure for reduction of
acylferrocenes
Compound 4b was also prepared from the alcohol 3b
by the following procedure. A mixture of 3b (230 mg, 1
mmol) and water (98 mg, 5.5 mmol) in THF (10 ml)
was added to a THF solution (40 ml) of SmI2 (3.6
mmol). The mixture was heated under reflux for 50
min, cooled, and filtered through a pad of silica gel by
elution with EtOAc–hexane (1:1) to give a practically
A deep blue SmI2 solution (0.1 M, 1.8 mmol) was
prepared by treatment of Sm (330 mg, 2.2 mmol) with
1,2-diiodoethane (500 mg, 1.8 mmol) in anhydrous
THF (18 ml) for 1.5 h at room temperature (r.t.). After
addition of H2O (135 mg, 7.5 mmol), the mixture was
cooled in an ice bath, and a solution of 1b (160 mg, 0.7
mmol) in THF (5 ml) was added. After stirring for 10
min at 0°C, the reaction was quenched by ice water (2
ml). The mixture was filtered through a pad of silica gel
column, and the filtrate was concentrated to give a
practically pure product of 3b (148 mg, 92%).
1
pure sample of 4b (211 mg, 99%) as shown by H- and
13C-NMR analyses. 13C-NMR (CDCl3, 50 MHz) l
14.6, 22.2, 66.8 (2 C), 67.4 (2 C), 68.3 (5 C), 91.0. Anal.
Calc. for C12H14Fe: C, 67.30; H, 6.59. Found: C, 67.05;
H, 6.50.
3.2.1. Ferrocenylmethanol [4b], 3a
3.3.3. Benzylferrocene [6f], 4c
According to the representative procedure (Section
3.2), ferrocenecarbaldehyde (150 mg, 0.7 mmol) was
treated with SmI2 in THF at 0°C for 10 min to give 3a
According to the representative procedure (Section
3.3), benzoylferrocene (290 mg, 1 mmol) was treated
with SmI2 in refluxing THF for 16 h to give 4c (122 mg,
44%) after chromatography on a silica gel column (3:97
EtOAc–hexane). 13C-NMR (CDCl3, 50 MHz) l 36.0,
67.5 (2 C), 68.6 (7 C), 87.9, 125.8, 128.2 (2 C), 128.3 (2
C), 141.5. FAB-MS m/z 276 (M+).
1
(141 mg, 93%). H-NMR (CDCl3, 200 MHz) l 4.30 (2
H, s), 4.21 (2 H, m), 4.15 (5 H, s), 4.14 (2 H, m), 1.89
(1 H, s). 13C-NMR (CDCl3, 50 MHz) l 60.6, 67.9 (2 C),
68.2 (7 C), 88.1.
3.2.2. 1-Ferrocenylethanol [4a], 3b
3.3.4. 1,1%-Diethylferrocene [6f], 5
1H-NMR (CDCl3, 300 MHz) l 4.56 (1 H, q, J=6.3
Hz), 4.17–4.06 (9 H, m), 2.19 (1 H, s), 1.41 (3 H, d,
J=6.3 Hz). 13C-NMR (CDCl3, 50 MHz) l 23.5, 65.3,
65.8, 66.1, 67.6, 67.7, 68.1 (5 C), 94.3.
According to the representative procedure (Section
3.3), 1,1%-diacetylferrocene (270 mg, 1 mmol) was
treated with SmI2 in refluxing THF for 16 h to give 5
(162 mg, 67%) after chromatography on a silica gel
column by elution with hexane and EtOAc–hexane
(3:97). 13C-NMR (CDCl3, 50 MHz) l 15.4 (2 C), 22.7
(2 C), 68.1 (4 C), 68.5 (4 C), 91.6 (2 C). FAB-MS m/z
242 (M+).
3.3. Representati6e procedure for deoxygenation of
acylferrocenes
A deep blue SmI2 solution (0.11 M, 8.0 mmol) was
prepared by treatment of Sm (1.20 g, 8.0 mmol) with
1,2-diiodoethane (2.25 g, 8.0 mmol) in anhydrous THF
(70 ml) for 1.5 h at r.t. After addition of H2O (360 mg,
20 mmol), a solution of 1a (214 mg, 1.0 mmol) in THF
(10 ml) was added in one portion. The mixture was
heated under reflux for 4 h. The serum cap was re-
moved, and hexane (20 ml) was added. The resulting
precipitates were removed by passing through a pad of
silica gel, and the crude product was obtained by
3.4. 1,2-Diferrocenyl-1,2-ethanediol [11], 6
Ferrocenecarbaldehyde (214 mg, 1 mmol) was treated
with SmI2 (8 mmol) in anhydrous THF under reflux for
48 h. After addition of ice water (50 ml), the mixture
was extracted with CHCl3 (30 ml×10). The extracts
were combined, washed with water, concentrated, and
crystallized from MeOHꢀH2O to give the pinacols 6 (90
mg, 42%) as a mixture of two stereomers (1:1). 1H-