1
145.1 and 153.6 (C6H4, C6H5, NC5H4, C6H5CH3). 29Si{ H} NMR
138.2*, 141.4, 143.1, 144.0, 144.4 and 153.7 (C6H4, C6H5, NC5H4,
1
C6H5CH3, NCO). 29Si{ H} NMR (59.6 MHz, CD2Cl2): d -87.9.
(59.6 MHz, CD2Cl2): d -81.7. 13C VACP/MAS NMR: d 23.7
(C6H5CH3), 46.0–49.3 (m (13C,14N coupling), NCH2C), 110.4,
112.0, 119.7, 120.8–124.1 (m, 4 C), 125.7, 126.7, 128.1 (2 C),
129.6 (2 C), 130.8 (2 C), 132.0–135.6 (m, 2 C), 138.8, 139.7, 142.2
(2 C), 147.3 and 152.8 (C6H4, C6H5, NC5H4, C6H5CH3). 15N
VACP/MAS NMR: d -300.0 (NCH2C), -294.2 (SiNNN), -194.8
(SiNNN), -137.8 (SiNNN), -131.5 (NC5H4). 29Si VACP/MAS
NMR: d -85 (br.). Anal. Calcd for C21.5H19N5SSi (407.57): C,
63.36; H, 4.70; N, 17.18; S, 7.87. Found: C, 63.4; H, 4.7; N, 16.9;
S, 8.1.
13C VACP/MAS NMR: d 21.9 (C6H5CH3), 45.3–48.8 (m (13C,14N
coupling), NCH2C), 110.3, 111.5, 118.7, 119.2, 120.2, 121.2, 121.4,
123.0 (3 C), 124.2, 124.5, 125.2, 127.9, 128.9, 129.7 (2 C), 136.0,
139.0, 141.2, 142.3 (2 C), 143.9 and 152.8 (C6H4, C6H5, NC5H4,
C6H5CH3, NCO). 15N VACP/MAS NMR: d -300.4 (NCH2C),
-178.4 (NCO), -126.1 (NC5H4). 29Si VACP/MAS NMR: d -89
(br.). Anal. Calcd for C22.5H19N3OSSi (407.57): C, 66.31; H, 4.70;
N, 10.31; S, 7.87. Found: C, 66.1; H, 4.7; N, 10.3; S, 7.6.
Pentacoordinate silicon(IV) complex 4. Trimethyl(thiocyanato-
N)silane (262 mg, 2.00 mmol) was added at 20 ◦C in a single
portion to a stirred solution of 1·0.5C7H8 (800 mg, 1.99 mmol)
in acetonitrile (20 ml), and the reaction mixture was stirred at
20 ◦C for 2 h. The volatile components were removed in vacuo,
and acetonitrile (20 ml) was added to the residue. The resulting
suspension was heated until a clear solution was obtained, which
was then cooled slowly to 20 ◦C and kept undisturbed at this
temperature for 1 d. The resulting yellow crystalline solid was
isolated by filtration, washed with n-pentane (5 ml) and dried in
vacuo (20 ◦C, 4 h, 0.01 mbar). Yield: 670 mg (1.77 mmol, 89%). Mp:
236 ◦C (dec.). 1H NMR (300.1 MHz, CD2Cl2): d 4.79 and 4.87 (AB
system, 2J(1H,1H) = 18.1 Hz, 2 H, NCH2C), 6.58–6.85, 6.92–7.08,
7.18–7.29, 7.29–7.37, 7.42–7.55, 7.66–7.73, 7.98–8.09 and 8.29–
Pentacoordinate silicon(IV) complex 6·0.5C7H8. Trifluoro-
methanesulfonatotrimethylsilane (442 mg, 1.99 mmol) was added
at 20 ◦C in a single portion to a stirred solution of 1·0.5C7H8
(800 mg, 1.99 mmol) in acetonitrile (20 ml), and the reaction
mixture was stirred at 20 ◦C for 2 h. The volatile components
were removed in vacuo, and toluene (20 ml) was added to the
residue. The resulting suspension was heated until a clear solution
was obtained, which was then cooled slowly to 20 ◦C and kept
undisturbed at this temperature for 1 d. The resulting yellow
crystalline solid was isolated by filtration, washed with n-pentane
◦
(5 ml) and dried in vacuo (20 C, 6 h, 0.01 mbar). Yield: 560 mg
◦
1
(1.09 mmol, 55%). Mp: 137 C (dec.). H NMR (300.1 MHz,
CD2Cl2): d 2.35 (s, 1.5 H, C6H5CH3), 4.88 and 4.96 (AB system,
2J(1H,1H) = 20.0 Hz, 2 H, NCH2C), 6.80–6.93, 7.03–7.39, 7.42–
7.52, 7.72–7.83 and 8.08–8.21 (m, 15.5 H, C6H4, C6H5, NC5H4,
1
8.35 (m, 13 H, C6H4, C6H5, NC5H4). 13C{ H} NMR (75.5 MHz,
CD2Cl2): d 48.8 (NCH2C), 111.4, 120.3, 122.8, 123.8, 125.0, 126.5,
1
128.4 (2 C), 128.9, 129.7, 130.3, 130.8 (2 C), 141.8, 142.5, 143.3,
C6H5CH3). 13C{ H} NMR (75.5 MHz, CD2Cl2; the resonance
1
143.8 and 153.8 (C6H4, C6H5, NC5H4, NCS). 29Si{ H} NMR
signals marked with an asterisk refer to the toluene molecule): d
21.5* (C6H5CH3), 48.5 (NCH2C), 111.8, 120.7, 122.9, 124.1, 124.9,
125.6*, 126.6, 128.5 (2 C), 128.6* (2 C), 129.3, 129.4* (2 C), 129.6,
131.0 (2 C), 138.3*, 141.9, 142.0, 142.5, 144.4 and 154.3 (C6H4,
(59.6 MHz, CD2Cl2): d -89.3. 13C VACP/MAS NMR: d 43.8–46.5
(m (13C,14N coupling), NCH2C), 47.1–49.4 (m (13C,14N coupling),
NCH2C), 110.9, 112.3, 120.9 (2 C), 121.6, 122.1, 123.0, 124.8 (3
C), 125.5 (2 C), 127.4, 128.2 (3 C), 128.7–130.3 (m, 6 C), 130.8
(2 C), 133.9, 138.8, 139.6, 140.3, 140.7–142.4 (4 C), 143.1, 143.9,
150.4 and 152.3 (C6H4, C6H5, NC5H4, NCS). 15N VACP/MAS
NMR: d -304.0 (NCH2C), -302.8 (NCH2C), -135.0 (NC5H4),
-123.1 (NC5H4), NCS not detected. 29Si VACP/MAS NMR:6 d
-90 (br.). Anal. Calcd for C19H15N3S2Si (377.57): C, 60.44; H, 4.00;
N, 11.13; S, 16.99. Found: C, 60.3; H, 4.1; N, 11.1; S, 17.0.
1
C6H5, NC5H4, C6H5CH3). 29Si{ H} NMR (59.6 MHz, CD2Cl2):
d -74.2. 13C VACP/MAS NMR: d 21.5 (C6H5CH3), 47.5–49.2 (m
(13C,14N coupling), NCH2C), 110.5, 111.8, 120.0, 121.2–124.5 (4
C), 125.4, 126.0, 126.8, 127.3, 128.2, 129.5 (3 C), 130.9, 132.3,
141.5, 142.1, 143.3 (2 C), 144.0 and 152.0 (C6H4, C6H5, NC5H4,
C6H5CH3), CF3 not detected. 15N VACP/MAS NMR: d -300.2
(NCH2C), -134.3 (NC5H4). 29Si VACP/MAS NMR: d -82 (br.).
Anal. Calcd for C22.5H19F3N2O3S2Si (514.62): C, 52.51; H, 3.72; N,
5.44; S, 12.46. Found: C, 52.1; H, 3.8; N, 5.5; S, 12.2.
Pentacoordinate silicon(IV) complex 5·0.5C7H8. Azido-
trimethylsilane (227 mg, 1.97 mmol) was added at 20 ◦C in
a single portion to a stirred solution of 1·0.5C7H8 (700 mg,
1.75 mmol) in toluene (50 ml), and the reaction mixture was
stirred at 20 ◦C for 2.5 h. The volatile components were removed in
vacuo, and toluene (30 ml) was added to the residue. The resulting
suspension was heated until a clear solution was obtained, which
was then cooled slowly to 20 ◦C and kept undisturbed at -20 ◦C
for 16 h. The resulting yellow crystalline solid was isolated by
filtration, washed with n-pentane (5 ml) and dried in vacuo
(20 ◦◦C, 5 h, 0.01 mbar). Yield: 354 mg (867 mmol, 50%). Mp:
Pentacoordinate silicon(IV) complex 7. Trichloromethylsilane
(2.63 g, 17.6 mmol) was added dropwise at 20 ◦C within 1 min to a
stirred solution of 14 (3.80 g, 17.6 mmol) and triethylamine (3.55
g, 35.1 mmol) in tetrahydrofuran (75 ml), and the reaction mixture
was stirred at 20 ◦C for 2 h. The resulting precipitate was filtered
off, washed with tetrahydrofuran (10 ml) and discarded. The
solvent of the filtrate (including the wash solution) was removed
in vacuo, followed by the addition of acetonitrile (14 ml). The re-
sulting suspension was heated until a ◦clear solution was obtained,
which was then cooled slowly to 20 C and kept undisturbed at
this temperature for 1 d. The resulting yellow crystalline solid
was isolated by filtration, washed with n-pentane (2 ¥ 5 ml) and
dried in vacuo (◦40 ◦C, 6 h, 0.01 mbar). Yield: 2.60 g (8.88 mmol,
50%). Mp: 208 C (dec.). 1H NMR (300.1 MHz, CD2Cl2): d 1.04
1
192 C (dec.). H NMR (300.1 MHz, CD2Cl2): d 2.35 (s, 1.5 H,
C6H5CH3), 4.79 and 4.87 (AB system, 2J(1H,1H) = 17.9 Hz, 2 H,
NCH2C), 6.74–6.85, 7.01–7.08, 7.12–7.29, 7.30–7.42, 7.60–7.66,
7.83–7.95, 8.27–8.33 and 8.39–8.47 (m, 15.5 H, C6H4, C6H5,
1
NC5H4, C6H5CH3). 13C{ H} NMR (75.5 MHz, CD2Cl2; the
2
resonance signals marked with an asterisk refer to the toluene
molecule): d 21.5* (C6H5CH3), 48.8 (NCH2C), 111.2, 119.9,
122.4, 123.7, 124.4, 125.6*, 126.9, 128.3 (2 C), 128.48, 128.51* (2
C), 129.3* (2 C), 130.0, 130.1 (2 C), 138.3*, 141.4, 143.4, 144.5,
(s, 3 H, CH3), 4.69 and 4.72 (AB system, J(1H,1H) = 17.8 Hz,
2 H, NCH2C), 6.34–6.44, 6.61–6.78, 6.93–7.09, 7.19–7.26, 7.38–
8.09, 8.25–8.40, 8.62–8.69 and 8.77–8.81 (m, 8 H, C6H4, NC5H4).
1
13C{ H} NMR (75.5 MHz, CD2Cl2): d 16.1 (CH3), 48.6 (NCH2C),
2150 | Dalton Trans., 2012, 41, 2148–2162
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