R. M. Gauvin, C. Lorber, R. Choukroun, B. Donnadieu, J. Kress
FULL PAPER
δ ϭ 4.39 and 3.68 coalesce into a broad singlet at δ ϭ 3.96 (2 H);
9 H, CH2NSiMe3). Ϫ 13C NMR (C6D6, 75 MHz): δ ϭ 151.23 (C2),
Tc ϭ 314 K. Ϫ 13C NMR (C6D6, 75 MHz): δ ϭ 157.26 (C2), 136.53 137.8 (C1), 129.10, 128.23, 123.53, 120.38 (C3ϪC6), 49.71 (CH2),
(C1), 131.60, 129.62, 125.83, 119.11 (C3ϪC6), 48.78 (CH2), 2.96 41.92 (NMe2), 1.43 (SiMe3), 0.95 (SiMe3).
(SiMe3), 0.60 (SiMe3). Ϫ IR (nujol mull): No absorptions above
Zr[(SiMePh2)2-ABA](NMe2)2 (4b): This compound was prepared
3000 cmϪ1
.
from 1b according to the procedure described for 4a. It consists of
a very viscous orange oil (96% yield). Ϫ 1H NMR (C6D6,
300 MHz): δ ϭ 7.70 (m, 4 H, Ho SiMePh2), 7.62 (m, 4 H, Ho Si-
MePh2), 7.20 (m, 12 H, Hm ϩ Hp SiMePh2), 7.08, 6.97 (d, 1 H, H3
and H6), 6.95, (t, 1 H, H4 or H5), 6.70 (t, 1 H, H4 or H5), 4.61 (s,
2 H, CH2), 2.45 (s, 12 H, NMe2), 0.74 (s, 3 H, SiMePh2), 0.65 (s,
3 H, SiMePh2). Ϫ 13C NMR (CD2Cl2, 75 MHz): δ ϭ 151.56 (C2),
139.13, 137.16, 136.67 (C2 and Cipso SiMePh2), 135.77, 135.13 (Co
SiMePh2), 130.30, 129.46 (Cp SiMePh'2), 128.96 (Ar), 128.20,
128.04 (Cm SiMePh2), 127.79, 124.01, 119.88 (Ar), 50.42 (CH2),
41.60 (NMe2), Ϫ1.12 (SiMePh2), Ϫ1.61 (SiMePh2). The C1 signal
could not be detected.
[(SiMePh2)2-ABA]Li2 (2b): This compound was prepared from 1b
according to the procedure described for 2a. After 48 h of stirring
at room temperature, the product was directly filtered as a white
powder that was dried in vacuo (34% yield). Ϫ 1H NMR (C6D6,
300 MHz): δ ϭ 7.46 (m, broad, 20 H, SiMePh2), 6.70 (m, 2 H, Ar),
6.67, 6.17 (m, 1 H, Ar), 4.02 (s, broad, 2 H, CH2), 0.40 (s, 3 H,
ArNSiMePh2), 0.13 (s, 3 H, CH2NSiMePh2). Ϫ IR (nujol mull):
No absorptions above 3000 cmϪ1
.
[(SiMe2tBu)2-ABA]Li2 (2c): This compound was prepared from 1c
according to the procedure described for 2a. After 24 h of stirring
at room temperature, the product was obtained as a thick brown
oil after concentration to dryness, that eventually solidified as an
off-white solid (80% yield). Ϫ 1H NMR (C6D6, 200 MHz): δ ϭ
7.20 (s, 1 H, H4 or H5), 7.05 (m, 2 H, H3 and H6), 6.56 (t, 1 H, H4
or H5), 4.37 (s, 2 H, CH2), 1.16 (s, 9 H, tBu), 1.15 (s, 9 H, tBu),
0.33 (s, 6 H, ArNSiMe2tBu), 0.19 (s, 6 H, CH2NSiMe2tBu).
Zr[(SiMe2tBu)2-ABA](NMe2)2 (4c): This compound was prepared
from 1c according to the procedure described for 4a, along with 5
d of stirring at room temperature in pentane, or 4 h in refluxing
toluene. The product was further purified by extraction with pent-
ane (orange oil, 99% yield). Ϫ 1H NMR (C6D6, 250 MHz): δ ϭ
7.20Ϫ7.09 (m, 3 H, Ar), 6.82 (t, 1 H, H4 or H5), 4.60 (s, broad, 2
H, CH2), 2.80 (s, 12 H, NMe2), 1.04 (s, 9 H, tBu), 1.03 (s, 9 H,
tBu), 0.29 (s, 6 H, ArNSiMe2tBu), 0.16 (s, 6 H, CH2NSiMe2tBu).
Ϫ C23H48N4Si2Zr (436.8): calcd. C 52.32, H 9.16, N 10.61; found
C 52.29, H 9.77, N 10.73.
[(SiiPr3)2-ABA]Li2 (2d): This compound was prepared as a viscous
brown oil from 1d according to the procedure described for 2c (95%
1
yield). Ϫ H NMR (C6D6, 300 MHz): δ ϭ 7.10 (m, 2 H, Ar), 6.97
(d, 1 H, H3 or H6), 6.70 (t, 1 H, H4 or H5), 4.23 (s, broad, 2 H,
CH2), 1.15 (m, 42 H, Si-iPr3).
Zr[(SiMePh2)(SiMe3)-ABA](NMe2)2 (4g): This compound was pre-
pared from 1g according to the procedure described for 4a. It con-
sists of a yellow oil (98% yield). Ϫ 1H NMR (C6D6, 300 MHz):
δ ϭ 7.65 (m, 4 H, Ho SiMePh2), 7.14 (m, 7 H, Hm ϩ Hp SiMePh2
and H3 or H6), 7.06 (d, 1 H, H3 or H6), 6.89, 6.73 (dt, 1 H, H4
and H5), 4.52 (s, 2 H, CH2), 2.63 (s, 12 H, NMe2), 0.79 (s, 3 H,
ArNSiMePh2), 0.14 (s, 9 H, CH2NSiMe3). Ϫ 13C NMR (C6D6,
75 MHz): δ ϭ 152.18 (C2), 136.96 (Cipso SiMePh2), 136.10, 135.96
(C1 and Co SiMePh2), 130.27 (Cp SiMePh2), 128.61 (Ar), 128.14
(Cm SiMePh2), 127.85, 122.90, 119.74 (Ar), 49.14 (CH2), 41.88
(NMe2), 1.22 (CH2NSiMe3), Ϫ1.21 (ArNSiMePh2). Ϫ 13C NMR
(CD2Cl2, 75 MHz): δ ϭ 152.80 (C2), 136.59, 136.38 (C1 and Cipso
SiMePh2), 135.91 (Co SiMePh2), 130.48 (Cp SiMePh2), 128.32 (Ar),
128.25 (Cm SiMePh2), 127.30, 122.23, 119.98 (Ar), 48.67 (CH2),
41.95 (NMe2), 1.04 (CH2NSiMe3), Ϫ1.36 (ArNSiMePh2).
[(SiMePh2)(SiMe3)-ABA]Li2 (2g): This compound was obtained as
a white powder from 1g according to the procedure described for
1
2b (45% yield). Ϫ H NMR (C6D6, 300 MHz, 286 K): δ ϭ 7.69 (d,
2 H, Ho SiMePhPhЈ), 7.48 (d, 2 H, Ho SiMePhPhЈ), 7.23 (m, 6 H,
H
m ϩ Hp SiMePh2), 6.77 (dt, 1 H, H4 or H5), 6.60 (dd, 1 H, H3 or
H6), 6.50 (dt, 1 H, H4 or H5), 6.12 (d, 1 H, H3 or H6), 4.56 (d,
2J ϭ 11.9 Hz, 1 H, CHHЈ), 3.60 (d, 2J ϭ 11.9 Hz, 1 H, CHHЈ),
0.48 (s, 3 H, ArNSiMePh2), 0.01 (s, 9 H, CH2NSiMe3). Ϫ IR (nujol
mull): No absorptions above 3000 cmϪ1
.
Zr[(SiMe2tBu)2-ABA]2 (3c): This compound was obtained from 2c
according to the procedure described for 3g (52% yield). Ϫ 1H
NMR (C6D6, 200 MHz): δ ϭ 7.16Ϫ7.00 (m, 6 H, Ar), 6.88 (d, 2
H, H3 or H6), 4.80 (s, broad, 2 H, CHHЈ), 4.05 (s, broad, 2 H,
CHHЈ), 1.08 (s, 18 H, tBu), 0.82 (s, 18 H, tBu), 0.44 (s, 12 H,
ArNSiMe2tBu), 0.15 (s, 12 H, CH2NSiMe2tBu).
Zr[(SiMe3)2-ABA]Cl2 (5a): To
a solution of 830 mg of 4a
(1.9 mmol) in 40 mL of pentane at Ϫ50 °C, 2.4 mL of chlorotrime-
thylsilane (19 mmol) was added. After room temperature had been
reached, the reaction mixture was vigorously stirred overnight.
After filtration, washing of the precipitate with cold pentane
(20 mL) and drying in vacuo, one obtained 622 mg of a pale yellow
solid (78%). Ϫ 1H NMR (C6D6, 300 MHz): δ ϭ 7.00 (m, 2 H, Ar),
6.77 (m, 2 H, Ar), 4.72 (s, 2 H, CH2), 0.43 (s, 9 H, ArNSiMe3),
0.15 (s, 9 H, CH2NSiMe3). Ϫ 13C NMR (C6D6, 75 MHz): δ ϭ
149.81 (C2), 132.22 (C1), 128.72, 128.72, 122.47, 120.24 (C3ϪC6),
Zr[(SiMePh2)(SiMe3)-ABA]2 (3g): A mixture of 25 mg of ZrCl4
(0.11 mmol) and 86 mg of 2g (0.22 mmol) in 15 mL of toluene was
stirred at 80 °C for 48 h. After cooling to room temperature, the
mixture was centrifuged and the clear yellow solution was concen-
trated to dryness to yield 71 mg of a yellow solid (76%). Ϫ 1H
NMR (CD2Cl2, 300 MHz): δ ϭ 7.25 (m, 22 H, SiMePh2 ϩ Ar),
2
6.99 (m, 4 H, Ar), 6.55 (m, 2 H, Ar), 4.89 (d, J ϭ 13.4 Hz, 2 H,
2
CHHЈ), 3.93 (d, J ϭ 13.4 Hz, 2 H, CHHЈ), 0.53 (s, 6 H, ArNSi-
MePh2), 0.09 (s, 18 H, CH2NSiMe3).
˜
49.50 (CH2), 0.56 (SiMe3), 0.45 (SiMe3). Ϫ IR (nujol mull): ν ϭ
313 (f), 289 (m) and 254 (F, broad) cmϪ1, (νZrϪCl).
Zr[(SiMe3)2-ABA](NMe2)2 (4a): To
a solution of 497 mg of
Zr(NMe2)4 (1.86 mmol) in 25 mL of pentane at Ϫ70 °C, a solution
Zr[(SiMe2tBu)2-ABA]Cl2 (5c): This compound was prepared from
of 497 mg of 1a (1.86 mmol) in 10 mL of pentane was added. After 4c according to the procedure described for 5a and a slightly differ-
room temperature had been reached, the reaction mixture was ent workup. The reaction mixture was first concentrated to dryness
stirred for one night. After evaporation of all volatiles under prim-
ary, and then secondary vacuum, 798 mg of a pale yellow oil (96%)
and the solid residue extracted with small amounts of toluene. Re-
moval of toluene and other volatiles under vacuum afforded a solid
was obtained. Ϫ 1H NMR (C6D6, 300 MHz): δ ϭ 7.14 (m, 2 H, that was washed again with 2ϫ1 mL of cold pentane and dried
Ar), 6.99 (d, 1 H, H3 or H6), 6.79 (dt, 2 H, H4 or H5), 4.42 (s, 2 under vacuum (55% yield). Ϫ 1H NMR (C6D6, 250 MHz): δ ϭ
H, CH2), 2.84 (s, 12 H, NMe2), 0.32 (s, 9 H, ArNSiMe3), 0.13 (s, 7.20 (m, 2 H, Ar), 7.00Ϫ6.96 (m, 2 H, Ar), 4.59 (s, 2 H, CH2), 1.02
2344
Eur. J. Inorg. Chem. 2001, 2337Ϫ2346