1H, CH(CH3)2), 3.05 (br sept, 2H, CH(CH3)2), 2.80 (br sept,
solution at -30 ◦C over several days afforded 3 as yellow crystals
(0.501 g, 0.84 mmol, 45% yield).
3
1H, CH(CH3)2), 2.40 (br s, 12H, N(CH3)2), 1.40 (br d, 3H, JHH
3
1
=
H NMR (400.1 MHz, C6D6): d 8.84 (s, 1H, HC N), 8.57 (d,
4 t
5.8 Hz CH(CH3)2), 1.31 (br d, 3H, JHH 5.9 Hz CH(CH3)2),
3
3
1.11 (d, 12H, JHH 6.7 Hz CH(CH3)2), 1.00 (br d, 3H, JHH
1H, JHH 2.6 Hz, 6-C6H2), 7.55 (s, 2H, 3 + 5-C6H2 Bu3), 7.21 (d,
5.9 Hz CH(CH3)2), 0.88 (br d, 3H, JHH 5.6 Hz CH(CH3)2); 13C
1H, JHH 2.7 Hz, 4-C6H2), 2.04 (s, 6H, N(CH3)2), 1.46 (s, 18H,
3
4
NMR (100.6 MHz, C6D6): d 165.54 (HC=N), 162.45 (1/2/3/5-
C6H2), 158.94 (1/2/3/5-C6H2), 148.93 (1-C6H3), 144.91 (1-C6H3),
141.17 (2/6-C6H3), 140.77 (2/6-C6H3), 138.48 (2 coincident
resonances, 2/6-C6H3), 133.63 (4/6-C6H2), 133.03 (2 coincident
resonances, 4/6-C6H2), 132.83 (4/6-C6H2), 127.23 (3/4/5-C6H3),
125.48 (3/4/5-C6H3), 123.71 (3 coincident resonances, 3/4/5-
C6H3), 122.82 (3/4/5-C6H3), 121.78 (1/2/3/5-C6H2), 120.73
(1/2/3/5-C6H2), 41.22 (N(CH3)2), 28.48 (3 coincident reso-
nances, CH(CH3)2), 27.72 (CH(CH3)2), 25.44 (CH(CH3)2), 25.28
(CH(CH3)2), 24.10 (5 coincident resonances, CH(CH3)2), 23.88
(CH(CH3)2); 119Sn NMR (186.4 MHz, C6D6): d -664. (Found: C,
49.00; H, 4.99; N, 5.60. C21H26N2OCl2Sn requires C, 49.26; H,
5.12; N, 5.47%).
2 + 6-C(CH3)3), 1.34 (s, 9H, 4-C(CH3)3); 13C NMR (100.6 MHz,
t
C6D6): d 158.47 (2-C6H2), 157.68 (HC=N), 151.44 (1-C6H2 Bu3),
t
t
144.63 (4-C6H2 Bu3), 138.86 (2 + 6-C6H2 Bu3), 132.09 (4-C6H2),
126.83 (6-C6H2), 124.13 (3/5-C6H2), 123.32 (3/5-C6H2), 121.90
t
(3/5-C6H2 Bu3), 40.40 (N(CH3)2), 36.22 (2 + 6-C(CH3)3), 34.84
(4-C(CH3)2), 32.08 (2 + 6-C(CH3)3), 31.81 (4-C(CH3)3), 1-C6H2
was not found; 119Sn NMR (186.4 MHz, C6D6):d -107. (Found:
C, 54.56; H, 6.17; N, 4.60. C27H36N2OCl2Sn requires C, 54.58; H,
6.11; N, 4.71%).
[2,4-tBu2–6-{CH(NMe2)N-2,4,6-Br3C6H2}-C6H2O]Sn, 4
A 30 cm3 diethyl ether solution containing 0.800 g [tBuONTBP]H
(1.46 mmol) was added to a diethyl ether solution (20 cm3 of
Sn(NMe2)2 (0.318 g, 1.54 mmol) at -78 ◦C. After allowing to
stir for 2 h at room temperature the reaction was concentrated
under reduced pressure to afford a yellow solid. Analytically pure
4 was then obtained by recrystallising from a minimum amount
of diethyl ether stored at -30 ◦C for 18 h (0.599 g yellow crystals,
0.85 mmol, 58% yield). Crystals suitable for X-ray crystallography
were grown by allowing a saturated diethyl ether solution to stand
at room temperature for several days.
[IONDIPP]Sn(NMe2), 2
A diethyl ether solution (30 cm3) of [IONDIPP]H (1.1015 g,
1.91 mmol) was added dropwise to a solution of Sn(NMe2)2
(0.397 g, 1.92 mmol) in diethyl ether (20 cm3) chilled to -78 ◦C. The
mixture was then stirred for 2 h at room temperature, affording a
yellow precipitate. The volatile components were removed under
reduced pressure and yellow (X-ray diffraction quality) crystals of
2 were obtained by allowing a saturated toluene solution to cool
from 70 ◦C to room temperature (0.815 g, 1.17 mmol, 61% yield).
4
1H NMR (400.1 MHz, C6D6): d 7.53 (d, 1H, JHH 2.6 Hz, 4-
4
C6H2), 7.13 (s, 2H, 3 + 5-C6H2Br3), 6.73 (d, 1H, JHH 2.7 Hz,
6-C6H2), 6.62 (s, 1H, HC-N), 2.34 (s, 3H, N(CH3)2), 1.84
(s, 3H, N(CH3)2), 1.80 (s, 9H, 3-C(CH3)3), 1.20 (s, 9H, 5-
C(CH3)3); 13C NMR (100.6 MHz, C6D6): d 154.59 (2-C6H2),
146.17 (1-C6H2Br3), 138.53 (5-C6H2), 138.17 (3-C6H2), 135.20
(2/4/6 + 3+5-C6H2Br3), 125.24 (4-C6H2), 123.88 (6-C6H2),
118.98 (2/4/6-C6H2Br3), 109.76 (2/4/6-C6H2Br3), 88.44 (HC-
N), 43.90 (N(CH3)2), 40.68 (N(CH3)2), 35.54 (3-C(CH3)3), 34.02
(5-C(CH3)2), 31.80 (5-C(CH3)3), 30.28 (3-C(CH3)3); 119Sn NMR
(186.4 MHz, C6D6): d -194. (Found: C, 38.95; H, 4.06; N, 3.90.
C23H29N2OBr3Sn requires C, 39.02; H, 4.13; N, 3.96%).
1H NMR (400.1 MHz, C6D6): d 8.14 (d, 1H, 4JHH 2.3 Hz, C6H2),
4
=
8.04 (br, 1H, C6H2/HC N), 7.95 (d, 1H, JHH 2.3 Hz, C6H2), 7.38
4
=
(s, 1H, HC N), 7.27 (d, 1H, JHH 2.3 Hz, C6H2), 7.18–7.00 (m,
=
7H, C6H3+C6H2/HC N), 4.17 (br sept, 1H, CH(CH3)2), 3.04 (br
sept, 2H, CH(CH3)2), 2.69 (br sept, 1H, CH(CH3)2), 2.61 (br s,
3
12H, N(CH3)2), 1.39 (br d, 3H, JHH 5.6 Hz CH(CH3)2), 1.31
3
3
(br d, 3H, JHH 5.7 Hz CH(CH3)2), 1.12 (d, 12H, JHH 6.8 Hz
3
CH(CH3)2), 0.93 (br d, 3H, JHH 6.4 Hz CH(CH3)2), 0.89 (br d,
3H, 3JHH 6.2 Hz CH(CH3)2); 13C{ H} NMR (100.6 MHz, C6D6):
1
=
d 165.43 (HC N), 163.42 (1/2/3/5-C6H2), 162.70 (1/2/3/5-
C6H2), 150.71 (4/6-C6H2), 150.38 (4/6-C6H2), 144.94 (4/6-C6H2),
144.47 (1-C6H3), 141.20 (2/6-C6H3), 140.86 (2/6-C6H3), 138.78
(2 coincident resonances, 2/6-C6H3), 127.13 (2 coincident res-
onances, 3/4/5-C6H3), 125.60 (2 coincident resonances, 3/4/5-
C6H3), 123.75 (2 coincident resonances, 3/4/5-C6H3), 123.42
(1-C6H3/1-C6H2), 96.52 (1/2/3/5-C6H2), 96.14 (1/2/3/5-C6H2),
78.45 (1/2/3/5-C6H2), 76.72 (1/2/3/5-C6H2), 43.42 (N(CH3)2),
28.51 (3 coincident resonances, CH(CH3)2), 28.08 (CH(CH3)2),
26.08 (CH(CH3)2), 25.71 (CH(CH3)2), 24.17 (5 coincident reso-
nances, CH(CH3)2), 23.63 (CH(CH3)2); 119Sn NMR (186.4 MHz,
C6D6): d -639. (Found: C, 36.28; H, 3.81; N, 3.90. C21H26N2OI2Sn
requires C, 36.29; H, 3.77; N, 4.03%).
Crystal data for 2. C42H52I4N4O2Sn2, M = 1389.86, triclinic,
˚
space group P¯ı, a = 8.6381(5), b = 10.0747(6), c = 14.7661(8) A,
a = 71.3596(9), b = 85.7434(10), g = 79.4997(9)◦, U = 1197.07(12)
3
-1
˚
˚
A , T = 150(2) K, Z = 1, m(Mo-Ka) = 3.659 mm , l = 0.71073 A,
10669 reflections measured, 5538 unique (Rint = 0.0170) which
were used in all calculations. The final wR2 = 0.0556 (all data) and
R1 = 0.0247 (for 4588 data with F2 > 2s(F2)). CCDC 696308.
Crystal data for 4. C23H29Br3N2OSn, M = 707.90, triclinic,
space group P¯ı, a = 9.0297(2), b = 10.2931(3), c = 14.0540(4)
◦
˚
A, a = 78.4205(12), b = 88.3895(17), g = 80.8048(18) , U =
3
-1
˚
1263.19(6) A , T = 120(2) K, Z = 2, m(Mo-Ka) = 5.773 mm ,
˚
l = 0.71073 A, 22501 reflections measured, 5749 unique (Rint
=
0.0485). wR2 = 0.0734 (all data); R1 = 0.0301 (for 4961 data with
F2 > 2s(F2)). CCDC 696309.
[ClONTTBP]Sn(NMe2), 3
A 30 cm3 diethyl ether solution of [ClONTTBP]H (0.802 g, 1.85 mmol)
was added to Sn(NMe2)2 (0.385 g, 1.86 mmol, 20 cm3 diethyl
ether) at -78 ◦C. After allowing to warm to room temperature,
the reaction was stirred for 2 h and volatiles removed in vacuo to
give a yellow powder. Recrystallisation from a saturated toluene
Polymerisation procedure
In a N2 atmosphere glove box, 10 ml toluene was added to a solid
mixture of rac-LA (0.4036 g, 0.28 mmol) and the tin-based initiator
(0.0028 mmol), and a magnetic stirrer was added. This mixture
3714 | Dalton Trans., 2009, 3710–3715
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