2198
C.-Y. Wu et al. / Journal of Organometallic Chemistry 689 (2004) 2192–2200
FTIR spectrophotometer. Elemental analyses were
performed using a Perkin–Elmer 2400, 2400II elemental
analyzer. Crystals for X-ray diffraction were obtained
from n-hexane (3), methanol/n-hexane (7), dichlorome-
thane/n-hexane (8), and acetonitrile (9). A single crystal
was mounted on a glass fiber and the X-ray diffraction
intensity data were measured on a Rigaku AFC7S dif-
fractometer (3) or a Bruker Smart 1000 CCD XRD (7,
mixture was filtered through Celite 545 and the solvent
was removed under reduced pressure. The residue was
chromatographed on a silica gel column with n-hexane
as eluent to separate the resulting red product 2 and
yellow product 3. The column was further treated with
n-hexane/ethyl acetate (5/1) as eluent to obtain another
yellow product 4.
Compound 2: 0.37 mmol, 23% yield; m.p. 108.6–
109.0 °C. IR (CHCl3) mmax (CO) 2041, 2014, 1993 cm 1.
Anal. Calc. for C9Fe3O9S2: C, 22.31; S, 13.22. Found:
C, 22.53; S, 13.06%.
ꢀ
8
, and 9).
3
.1. Synthesis of thienyl Schiff bases N-(5-methyl-2-
thienylmethylidene)-2-thiolethylamine (1) and N-(6-
methyl-2-pyridylmethylidene)-2-thiolethylamine (6)
Compound 3: 0.45 mmol, 14% yield; m.p. 101.5–
1
102.0 °C. H NMR (CDCl3): d 6.78 (d, JH–H ¼ 3.3 Hz,
1
H), 6.59 (d, J
¼ 3:3 Hz, 1H), 4.44 (s, 2H), 2.62 (t,
H–H
H–H
The synthesis of Schiff base employed the usual
approach of condensation in ethanol solution [14]. 37
mmol of 2-aminoethanethiol hydrochloride was
stirred with 50 mmol of sodium hydroxide in 50 ml
distilled water for 4 h. 2-Aminoethanethiol was ex-
tracted with dichloromethane five times. After the con-
centration, the extracted 2-aminoethanethiol was mixed
with 40 mmol of 5-methyl-2-thiophenecarboxaldehyde
or 6-methyl-2-pyridinecarboxaldehyde in 50 ml 95%
ethanol and the reaction mixture was heated at reflux for
JH–H ¼ 6:3 Hz, 2H), 2.47 (s, 3H), 2.36 (t, J
¼ 6:3 Hz,
1
3
2H) ppm. C NMR (CDCl ): d 207.4, 140.5, 138.9,
3
128.2, 124.4, 69.5, 62.4, 33.6, 15.5 ppm. IR (KBr film)
ꢀ
mmax (CN) 1631 cm 1; (CO) 2067, 2027, 1993, 1967
cm . MS (FAB): m/z 465 (M ), 437 (M –CO), 409
ꢀ
þ
1
þ
þ
þ
þ
þ
þ
(M –2CO), 381 (M –3CO), 353 (M –4CO), 325 (M –
þ
þ
5CO), 297 (M –6CO), 241 (M –6CO–Fe), 185 (L ).
Anal. Calc. for C H Fe NO S : C, 36.16; H, 2.37; N,
1
4
11
2
6 2
3.01; S, 13.79. Found: C, 36.18; H, 2.21; N, 2.99; S,
13.63%.
2
0 h. The reaction mixture was then filtered and the
Compound 4: 0.74 mmol, 23% yield; 1H NMR
(CDCl3): d 7.78 (d, JH–H ¼ 15:6 Hz, 1H), 7.30 (d, JH–H
¼ 3.6 Hz, 1H), 6.84 (d, JH–H ¼ 3:6 Hz, 1H), 6.80 (d,
solvent as well as unreacted starting material were re-
moved in vacuo over night to yield pure oily yellow
product 1 (29 mmol, 78% yield) or 6 (30 mmol, 81%
1
3
JH–H ¼ 15:6 Hz, 1H), 2.51 (s, 3H) ppm. C NMR
yield).
(CDCl3): d 145.1, 136.0, 132.7, 126.9, 123.4, 16.0 ppm.
1
ꢀ1
Compound 1. H NMR (CDCl ): d 8.26 (s, 1H), 7.09
IR (CHCl ) m
(CN) 1600 cm . MS (FAB): m/z 125
(M ). Anal. Calc. for C H NS: C, 57.56; H, 5.64; N,
3
3
max
þ
(
d, JH–H ¼ 3.5 Hz, 1H), 6.71 (d, JH–H ¼ 3:5 Hz, 1H),
6
7
3
2
1
.82 (t, JH–H ¼ 6:8 Hz, 2H), 3.00 (t, J
¼ 6:8 Hz, 2H),
11.20; S, 25.63. Found: C, 57.78; H, 5.82; N, 11.16; S,
25.37%.
H–H
13
.47 (s, 3H) ppm. C NMR (CDCl3): d 156.1, 144.5,
40.0, 131.4, 125.9, 59.9, 39.6, 15.9 ppm. IR (KBr film)
ꢀ
1
þ
mmax (CN) 1631 cm . MS (FAB): m/z 185 (M ). Anal.
Calc. for C8H11NS2: C, 51.89; H, 5.95; N, 7.57; S, 34.59.
Found: C, 51.76; H, 5.63; N, 7.75; S, 35.05%.
3.3. Reaction of 1 with Fe (CO) in acetonitrile at 45 °C
2
9
to yield N-(5-methyl-2-thienylmethyliden)amine (4), and
1
1
1
Compound 6. H NMR (CD COCD ): d 8.33 (s, 1H),
di-l-[N-(5-methyl-2-thienylmethylidene)-g (N);g (S)-
2-thiolethylamino]-l-carbonyl-tetracarbonyldiiron (5)
3
3
7
1
2
.85 (d, JH–H ¼ 7.8 Hz, 1H), 7.70 (t, J
¼ 7.8 Hz,
H–H
H), 7.25 (d, JH–H ¼ 7:8 Hz, 1H), 3.97 (t, J
¼ 6:6 Hz,
H–H
1
3
H), 3.13 (t, JH–H ¼ 6:6 Hz, 2H), 2.51 (s, 3H) ppm.
C
If the above mentioned reaction (Section 3.2) was
carried out at 45 °C, after an aluminum oxide (neu-
tral) column separation with n-hexane as eluent, only
reddish orange complex 5 and trace amount of 4 were
produced.
NMR (CD3COCD3): d 163.7, 158.0, 154.1, 136.6, 124.1,
1
1
17.6, 59.5, 39.3, 23.4 ppm. IR (KBr film) mmax (CN)
631 cm . MS (FAB): m/z 180 (M ). Anal. Calc. for
ꢀ
1
þ
C9H12N2S: C, 60.23; H, 6.40; N, 14.25; S, 14.53. Found:
C, 60.25; H, 6.59; N, 14.23; S, 14.51%.
Compound 5: 0.76 mmol, 48% yield; 1H NMR
(
CD3CN): d 8.29 (s, 2H), 7.15 (d, JH–H ¼ 3.3 Hz, 2H),
3
.2. Reaction of 1 with Fe (CO) in refluxing acetonitrile
9
6.77 (d, J
¼ 3:3 Hz, 2H), 3.70 (t, J
¼ 6:3 Hz, 4H),
2
H–H
H–H
to yield di-(l -thia)nonacarbonyltriiron (2), l-[N-(5-
2.73 (t, JH–H ¼ 6:3 Hz, 4H), 2.47 (s, 6H) ppm. IR
3
1
1
1
1
ꢀ1
þ
methyl-2-thienylmethyl)-g :g (N);g :g (S)-2-thiolatoe-
thylamido]hexacarbonyldiiron (3), and N-(5-methyl-2-
thienylmethylidene)amine (4)
(CH CN) m
(CO) 2068, 2031, 1983, 1732 cm ; (CN)
þ
3
max
ꢀ
1
1609 cm . MS (FAB): m/z 622 (M ), 594 (M –CO),
þ
þ
þ
566 (M –2CO), 538 (M –3CO), 510 (M –4CO), 482
þ
þ
þ
(M –5CO), 297 (M –5CO–L), 241 (M –5CO–Fe–L),
185 (L ). Anal. Calc. for C H Fe N O S : C, 40.53;
þ
3
.20 mmol of ligand 1 and 10.0 mmol of Fe (CO)
2
9
21 22
2
2
5 4
were heated at reflux in a 60 ml of anhydrous acetoni-
trile in the dark under nitrogen for 4 h. The reaction
H, 3.56; N, 4.50; S, 20.61. Found: C, 40.68; H, 3.70; N,
4.55; S, 20.52%.