L.-C. Song et al. / Journal of Organometallic Chemistry 648 (2002) 119–125
123
dures. 1H-NMR spectra were recorded on a Bruker
AC-P200 spectrometer, while IR spectra were recorded
on either a Bio-Rad FTS 135 or a Nicolet 560 E.S.P.
spectrometer. Elemental analyses and cyclic voltammet-
ric measurements were performed on a Elmentar Vario
EL analyzer and a BAS-100B electrochemical analyzer,
respectively. M.p. were determined on a Yanaco MP-
500 micromelting points apparatus.
was added 146 mg (1.0 mmol) of diallyl disulfide.
Similarly, 157 mg (48%) of 2 as a purple solid was
obtained. M.p. 55–56 °C. Anal. Found: C, 59.20; H,
5.94. Calc. for C16H20S2Ti: C, 59.25; H, 6.22%. IR (KBr
disk, cm−1): 3096w, 3009w, 2977w, 2930w, 2898w,
1629m, 1446m, 1427m, 1403m, 1367m, 1213m, 1020w,
1010w, 990m, 911s, 848s, 816s, 745w. 1H-NMR
(CHCl3-d): l=3.63(d, J=7.2 Hz, 4H, 2CH2), 4.87–
5.06 (m, 4H, 2CꢀCH2), 5.69–5.93 (m, 2H, 2CH), 6.13
(s, 10H, 2C5H5). When the ‘Cp2Ti’ solution prepared
through Method (i) was used, 160 mg (49%) of 2 was
obtained.
3.1. Two standard methods for preparation of
intermediate ‘Cp2Ti’
Method (i ): A 100 ml three-necked flask equipped
with a magnetic stir-bar, a serum cap and an Ar inlet
tube, was charged with 25 mg (1.0 mmol) of freshly
crushed Mg powders, 6 ml of THF and 249 mg (1.0
mmol) of bis(h5-cyclopentadienyl)dichlorotitanium.
The mixture was stirred at room temperature (r.t.) for
1–2 h until most of Mg disappeared to give a brown-
green solution of the intermediate bis(h5- cyclopentadi-
enyl)titanium ‘Cp2Ti’.
Method (ii ): The same equipped flask as in Method
(i) was charged with 50 mg (2.0 mmol) of fine Mg
turnings, 6 ml of THF and 0.085 ml (1.0 mmol) of
1,2-C2H4Br2. The reaction mixture was heated gently
with stirring until gas ceased emitting in about 5 min
and then 249 mg (1.0 mmol) of bis(h5-cyclopentadienyl)
dichlorotitanium was added. The mixture was stirred at
r.t. for about 0.5 h, at which time most of the activated
Mg disappeared to give a THF solution of the ‘Cp2Ti’
intermediate. The THF solution of the ‘Cp2Ti’ gener-
ated by either Method (i) or Method (ii) was employed
immediately in the following preparations and showed
no obviously different chemical behavior.
3.1.3. Preparation of (n-C5H11S)2TiCp2 (3)
To the ‘Cp2Ti’ solution prepared through Method (i)
was added 206 mg (1.0 mmol) of di-n-pentyl disulfide.
After similar workup 256 mg (67%) of 3 as a purple
solid was obtained. M.p. 54–55 °C. Anal. Found: C,
62.46; H, 8.44. Calc. for C20H32S2Ti: C, 62.48; H,
8.39%. IR (KBr disk, cm−1): 3074w, 2957w, 2926m,
2856w, 1463w, 1447w, 1428w, 1361w, 1027w, 1011w,
1
816s. H-NMR (CHCl3-d): l=0.83 (t, J=7.2 Hz, 6H,
2CH3), 1.16–1.59 (m, 12H, 6CH2), 3.01 (t, J=7.2 Hz,
4H, 2SCH2), 6.09 (s, 10H, 2C5H5).
3.1.4. Preparation of (MeO2CCH2S)2TiCp2 (4)
To the ‘Cp2Ti’ solution prepared through Method (i)
was added 210 mg (1.0 mmol) of (MeO2CCH2)2S2.
Similarly, after removal of solvent, the residue was
dissolved in CH2Cl2–Et2O (v/v=1:1), which was
filtered through a column packed with alumina. From
the filtrate 163 mg (42%) of 4 as a dark-purple solid
was obtained. M.p. 170–172 °C. Anal. Found: C,
49.20; H, 5.21. Calc. for C16H20O4S2Ti: C, 49.49; H,
5.19%. IR (KBr disk, cm−1): 3104w, 2946w, 1740m,
1712s(wCꢀO), 1442m, 1427m, 1292s 1268s 1149m, 1113m,
1006m, 820s. 1H-NMR (CHCl3-d): l=3.64 (s, 6H,
2CH3), 3.68 (s, 4H, 2CH2), 6.14 (s, 10H, 2C5H5).
3.1.1. Preparation of (1-C10H7S)2TiCp2 (1)
To the freshly prepared solution of ‘Cp2Ti’ through
Method (ii) was added 3 19 mg (1.0 mmol) of di-1-
naphthyl disulfide. The mixture turned purple immedi-
ately and was stirred at r.t. for an additional 2 h. The
solvent was removed under vacuum and the residue was
dissolved in CH2Cl2, which was filtered through a
column packed with alumina. Removal of solvent af-
forded 483 mg (93%) of 1 as a purple solid, which was
further purified by recrystallization from CH2Cl2ꢁ
C6H14. M.p. 85–86 °C. Anal. Found: C, 72.59; H, 4.75.
Calc. for C30H24S2Ti: C, 72.57; H, 4.87%. IR (KBr disk,
cm−1): 3115m, 3080m, 3050m, 1582w, 1555w, 1499m,
1441m, 1375s, 1320w, 1252w, 1194w, 1135w, 1057w,
1021m, 972s, 864m, 835vs, 796vs, 722vs, 664vs, 549m.
1H-NMR (CH3COCH3-d6): l=6.13 (s, 10H, 2C5H5),
7.10–8.45 (m, 14H, 2C10H7).
3.1.5. Preparation of (EtO2CCH2S)2TiCp2 (5)
To the ‘Cp2Ti’ solution prepared through Method (i)
was added 238 mg (1.0 mmol) of (EtO2CCH2)2S2. Sim-
ilarly, after removal of solvent, the residue was dis-
solved in Et2O, which was filtered through a column
packed with alumina. From the filtrate 247 mg (59%) of
5 as a red-purple solid was obtained. M.p. 144–145 °C.
Anal. Found: C, 51.80; H, 5.92. Calc. for
C18H24O4S2Ti: C, 51.92; H, 5.81%. IR (KBr disk,
cm−1): 3125w, 3078m, 2999w, 2936w, 1720s(wCꢀO),
1464m, 1436m, 1412m, 1389m, 1361m, 1278s 1196m,
1
1117s 1034s, 1015m, 845m, 822s. H-NMR (CHCl3-d):
l=1.26 (t, J=7.4 Hz, 6H, 2CH3), 3.73 (s, 4H,
2SCH2), 4.14 (q, J=7.4 Hz 4H, 20CH2), 6.21 (s, 10H,
2C5H5).
3.1.2. Preparation of (CH2=CHCH2S)2TiCp2 (2)
To the ‘Cp2Ti’ solution prepared through Method (ii)
Song, Li-Cheng
