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85.2 mmol) in benzene (200 mL) over a period of 1 h during ultra-
sound treatment. The deep red to black reaction mixture was
stirred for another hour and the ultrasonic bath was removed. The
dark red solution was carefully separated from all precipitates
through filtration through a broad Celite pad and subsequently all
volatiles were removed in vacuum. The reddish brown residue was
washed with a small amount of hexane (5 mL) at À788C, dissolved
in benzene, and the insoluble precipitate was filtered off. After re-
moval of the solvent under vacuum, compound 1 was isolated as
a deep red solid. Additionally, compound 1 can be obtained as
deep red to black crystals from a concentrated hexane solution
after storing at À708C for one day. The combined solids gave
[Ti(h6-C6H6)2] (1) as reddish-brown solid (912 mg, 4.47 mmol, 21%).
1H NMR (C6D6, 500.1 MHz): d=4.92 ppm (s, 12H; CH); 13C{1H} NMR
(C6D6, 125.8 MHz): d=79.41 ppm (CH); UV/Vis (5) (hexane): lmax
(e)=233 (3724), 285 (sh), 345 (20561), 500 nm (248 LmolÀ1 cmÀ1).
(CbenzeneH), 87.11 ppm (Cbenzene); 29Si{1H} NMR (C6D6, 99.4 MHz): d=
À21.72; UV/Vis (hexane): lmax (e)=239 (11256), 330 (sh), 375
(18653), 529 nm (412 LmolÀ1 cmÀ1); elemental analysis. calcd (%)
for C16H22Si2Ti (318.52): C 60.27, H 7.00; found: C 59.39, H 6.75.
[Ti(h6-C6H5SntBu2)2] (5): A slurry of [Ti(h6-C6H5Li)2]·pmdta (3·pmdta)
(250 mg, 0.64 mmol) in pentane (10 mL) was cooled to À788C and
treated dropwise over a period of 1 h with a solution of Cl2Sn2tBu4
(362 mg, 0.67 mmol) in pentane (5 mL). After complete addition
the reaction mixture was stirred for another 2 h at À788C and sub-
sequently allowed to warm to room temperature. During this time
the color of the suspension changed from pale brown to deep red
and a black precipitate formed. After 12 h all volatiles were re-
moved and the solid was washed with pentane (310 mL) and fil-
tered off. The deep red solution was concentrated to about 5 mL
and cooled to À708C overnight. The red precipitate was washed
with cold pentane (35 mL, À788C) and then dissolved in pentane
(20 mL) at room temperature. After filtration and removal of the
solvent, compound 5 was obtained as a dark red solid (156 mg,
0.23 mmol, 36%). Crystals were grown from a saturated pentane
solution at À308C. 1H NMR (500.1 MHz, C6D6): d=1.49 (s,
J(119Sn,1HtBu)=66, J(117Sn,1HtBu)=63 Hz, 18H; tBu), 5.04–5.08 (m, 2H;
CHbenzene), 5.16–5.20 (m, 4H; CHbenzene), 5.52–5.54 ppm (m, 4H;
CHbenzene); 13C{1H} NMR (125.8 MHz, C6D6): d=32.51 (J(119Sn,13C)=53,
[Ti(h6-C6H6)2(IMe)] (2): To a solution of [Ti(h6-C6H6)2] (1) (20 mg,
98 mmol) in C6D6 (0.3 mL) a solution of IMe (10 mg, 98 mmol) in
C6D6 (2 mL) was added. An immediate color change from deep red
to brown was observed. After filtration and recrystallization from
a saturated benzene solution, [Ti(h6-C6H6)2(IMe)] (2) was obtained
1
as black crystals (29 mg, 97 mmol, 98%). H NMR (500.1 MHz, C6D6):
d=3.42 (s, 6H; NCH3), 4.75 (s, 12H; CHbenzene), 6.18 ppm (s, 2H;
CHNHC); 13C{1H} NMR (125.8 MHz, C6D6): d=37.89 (NCH3), 79.33
(CbenzeneH), 119.50 ppm (CNHCH); UV/Vis (benzene): lmax (e)=356
(37517), 497 nm (415 LmolÀ1 cmÀ1); elemental analysis calcd (%)
for C17H20N2Ti (304.00): C 67.97, H 6.72, N 9.33; found: C 66.39, H
6.53, N 9.47.
J(117Sn,13C)=50 Hz,
SnC(CH3)3),
33.38
(J(117/119Sn,13C)=40 Hz,
SnC(CH3)3), 81.45 (CbenzeneH), 83.77 (J(117/119Sn,13C)=26 Hz, CbenzeneH),
90.44 (J(117/119Sn,13C)=30 Hz, CbenzeneH), 93.74 ppm (Cbenzene);
119Sn{1H} NMR (186.5 MHz, C6D6): À31.20 ppm (J(Sn,117/119Sn)=
1437 Hz, J(Sn,13C)=264 Hz); UV/Vis (hexane): lmax (e)=255 (sh), 325
(sh), 367 (15011), 522 nm (408 LmolÀ1 cmÀ1); elemental analysis
calcd (%) for C28H46Sn2Ti (667.95): C 50.35, H 6.94; found: C 49.89,
H 6.83.
Synthesis of [Ti(h6-C6H5Li)2]·pmdta (3·pmdta): A suspension of
[Ti(h6-C6H6)2] (1) (340 mg, 1.67 mmol) in pentane (15 mL) was treat-
ed with BuLi (2.60 mL, 4.16 mmol) and pmdta (721 mg, 4.16 mmol)
at room temperature and heated to 408C over a period of 12 h.
The resulting brown precipitate was collected by filtration, washed
with pentane (310 mL), and subsequently dried in vacuum to
afford [Ti(h6-C6H5Li)2]·pmdta (3·pmdta) as a brown powder (600 mg,
1.54 mmol, 92%). 1H NMR (D8[THF], 500.1 MHz): d=2.14 (s, 24H;
N(CH3pmdta)), 2.20 (s, 6H; N(CH3pmdta)), 2.31 (t, 8H; CH2pmdta), 2.41 (t,
8H; CH2pmdta), 4.67–4.73 (m, 6H; CHbenzene), 4.89–4.93 ppm (m, 4H;
CHbenzene); 13C{1H} NMR (D8[THF], 125.8 MHz): d=43.71 (N(CpmdtaH3)),
46.18 (N(CpmdtaH3)2), 56.67 (CpmdtaH2), 58.68 (CpmdtaH2), 76.67
(CbenzeneH), 77.59 (CbenzeneH), 87.91 (CbenzeneH), 123.30 ppm (Cbenzene);
7Li NMR (D8[THF], 194.4 MHz): d=2.26 ppm; elemental analysis
calcd (%) for C21H33Li2N3Ti (389.25): C 64.74, H 8.54, N 10.79; found:
C 64.72, H 8.94, N 10.42.
Synthesis of [Ti(h6-C6H5)2SiMe2] (6):
A solution of Cl2SiMe2
(236 mg, 1.84 mmol) in pentane (10 mL) was added dropwise to
a slurry of [Ti(h6-C6H5Li)2]·pmdta (3·pmdta) (598 mg, 1.54 mmol) in
pentane (25 mL) at À788C over 30 min. After complete addition,
the reaction mixture was allowed to warm to room temperature
and stirred for 12 h during which the color changed to deep red.
All volatiles were removed and the black precipitate was washed
with pentane (310 mL) and filtered off. The dark red filtrate was
reduced to 5 mL, cooled to À708C for 24 h, and the orange precip-
itate washed with cold pentane (35 mL) at À788C. Compound 6
was obtained as an orange solid after dissolving in pentane, filtra-
tion, and removal of all volatiles in vacuum (128 mg, 0.48 mmol,
32%). 1H NMR (C6D6, 500.1 MHz): d=0.05 (s, 6H; Si(CH3)2), 4.06–
4.08 (m, 4H; CHbenzene), 5.51—5.53 (m, 4H; CHbenzene), 5.59—
5.60 ppm (m, 2H; CHbenzene); 13C{1H} NMR (C6D6, 125.8 MHz): d=
À8.70 (Si(CH3)2), 40.41 (Cbenzene), 73.84 (CbenzeneH), 90.91 (CbenzeneH),
93.81 ppm (CbenzeneH); 29Si{1H} NMR (C6D6, 99.4 MHz): d=7.38; UV/
Synthesis of [Ti(h6-C6H5SiMe2)2] (4):
A slurry of compound
3·pmdta (250 mg, 0.64 mmol) in pentane (10 mL) was cooled to
À788C and treated dropwise over a period of 1 h with a solution
of Cl2Si2Me4 (126 mg, 0.67 mmol) in pentane (5 mL). After complete
addition the reaction mixture was stirred for another 2 h at À788C
and subsequently allowed to warm to room temperature. During
this time the color of the suspension changed from pale brown to
deep red and a black precipitate formed. After 12 h all volatiles
were removed and the solid was washed with pentane (310 mL)
and filtered off. The deep red solution was concentrated to about
5 mL and cooled to À708C overnight. The red precipitate was
washed with cold pentane (35 mL, À788C) and dissolved in pen-
tane (20 mL) at room temperature. After filtration and removal of
the solvent, compound 4 was obtained as a red solid (103 mg,
0.30 mmol, 46%). Crystals were grown from a saturated pentane
solution at À308C. 1H NMR (C6D6, 500.1 MHz): d=0.29 (s, 12H;
Si(CH3)2), 5.12–5.15 (m, 4H; CHbenzene), 5.19–5.24 (m, 2H; CHbenzene),
5.39–5.41 ppm (m, 4H; CHbenzene); 13C{1H} NMR (C6D6, 125.8 MHz):
d=À2.71 (Si(CH3)2), 83.66 (CbenzeneH), 84.40 (CbenzeneH), 85.60
Vis
(hexane):
lmax
(e)=245
(sh),
287
(3650),
345
(12129 LmolÀ1 cmÀ1), 460 nm (sh); elemental analysis calcd (%) for
C14H16SiTi (260.05): C 64.60, H 6.20; found: C 64.13, H 6.20.
Synthesis of [Ti(h6-C6H5)2GeMe2] (7): Over a period of 30 min a so-
lution of Cl2GeMe2 (170 mg, 0.99 mmol) in pentane (10 mL) was
added to a slurry of [Ti(h6-C6H5Li)2]·pmdta (3·pmdta) (320 mg,
0.82 mmol) in pentane (20 mL) at À788C. The reaction mixture was
allowed to warm to room temperature and was stirred at room
temperature over a period of 12 h. All volatiles were removed in
vacuum and the black precipitate was washed with pentane (3
10 mL) and filtered off. Concentrating the red solution to approxi-
mately 5 mL and storing the mixture at À708C overnight gave an
orange precipitate, which was washed with cold pentane (3
5 mL), dissolved in warm pentane, and separated from all insoluble
material by filtration. The solvent was removed to yield [Ti(h6-
Chem. Eur. J. 2015, 21, 11056 – 11064
11062
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