M.S. Hill et al. / Polyhedron 20 (2001) 1995–2002
1997
1
(m, 12H, CH2(CH2)2CH3); 5.30 (s, 2H, CH2); 7.21–7.30
(m, 2H, 4,3%-C4H2S); 7.66 (d, 2H, [J=3.3 Hz], 3,4%-
C4H2S), 3J(3,4%-C41H2Sꢀ117,119Sn)=14.8 Hz (unre-
solved). 13C NMR (l ppm): 10.8 (CH3); 13.6
H, 7.88. Calc. for C15H24S2Si2: C, 55.6; H, 7.41%. H
NMR (l ppm): 0.48 (s, 18H, CH3); 4.58 (s, 2H, CH2);
7.09–7.13 (m, 2H, 4,3%-C4H2S); 7.26 (m, 2H, 3,4%-
C4H2S). 13C NMR (l ppm): −0.03 (CH3); 30.2 (CH2);
126.7 (4,3%-C4H2S); 126.8 (3,4%-C4H2S); 134.0 (2,5%-
C4H2S); 148.5 (5,2%-C4H2S). 29Si NMR (l ppm): −6.8.
IR (liq. film, cm−1): 2953, 2897, 1464, 1262, 1250, 1214,
1157, 1097, 1042, 1033, 993, 839, 805, 757, 705.
(CH2(CH2)2CH3);
27.2
(CH2(CH2)2CH3);
28.9
(CH2(CH2)2CH3); 30.1 (CH2); 127.8 (4,3%-C4H2S); 135.1
(3,4%-C4H2S); 135.2 (2,5%-C4H2S); 148.9 (5,2%-C4H2S);
2
1J(13Cꢀ117,119Sn)=344.5, 356.9 Hz; J(13Cꢀ117,119Sn)=
3
20.9 Hz (unresolved); J(13Cꢀ117,119Sn)=47.4 Hz (unre-
solved). 119Sn NMR (l ppm): −39.4. 119mSn
Mo¨ssbauer (mm s−1): I.S.=1.21; Q.S.=0.61. IR (liq.
film, cm−1): 2959, 2926, 2872, 1464,1418, 1377, 1340,
1211, 1074, 961, 939, 875, 769, 698, 594.
2.7. Synthesis of 2-triphenylsilyl-5-[(5-triphenyl-
silylthien-2-yl)methyl]thiophene (7)
Compound 1 (2 g, 11.1 mmol), stirred in diethyl ether
(150 ml) under nitrogen, was treated with 1.6 M BuLi
(15 ml, 24 mmol) at room temperature giving a dark
brown solution. After stirring for 1 h, triphenylsilyl
chloride (6.55 g, 22.1 mmol) in diethyl ether (75 ml) was
added dropwise giving a dark brown suspension. This
was stirred for a further 1 h before filtration and
evaporation of the solvent. The resulting brown tar was
chromatographed on silica gel using 40–60° petroleum
ether as eluant to give 7 as an off-white amorphous
solid (2.2 g, 30%). Anal. Found: C, 77.1; H, 5.17. Calc.
2.5. Synthesis of 2-triphenylstannyl-5-[(5-triphenyl-
stannylthien-2-yl)methyl]thiophene (5)
Compound 1 (2.0 g, 11.1 mmol) was stirred in diethyl
ether (80 ml) under nitrogen. BuLi (1.6 M) in hexanes
(15 ml, 24 mmol) was added at room temperature over
a period of 1 h resulting in a dark brown solution. To
this was then added triphenyltin chloride (8.5 g, 22.0
mmol) in diethyl ether (80 ml) giving a brown suspen-
sion which was stirred for a further 2 h. This was then
filtered and the solvent evaporated giving a sticky dark
brown mass. Flash chromatography on silica gel using
a gradient of hexane to CH2Cl2 yielded 5 as an amor-
phous, pale yellow solid (3.8 g, 40%). Anal. Found: C,
61.4; H, 4.35. Calc. for C45H36S2Sn2: C, 61.5; H, 4.15%.
1H NMR (l ppm): 4.35 (s, 2H, CH2); 7.23–7.60 (m,
34H, o,m,p-C6H5, 3,4%-C4H2S, 4,3%-C4H2S). 13C NMR
(l ppm): 30.2 (CH2); 128.6 (4,3%-C4H2S); 128.7 (m-
C6H5); 129.3 (p-C6H5); 131.5 (3,4%-C4H2S); 137.0 (o-
C6H5); 137.5 (i-C6H5); 137.6 (2,5%-C4H2S); 150.0
(5,2%-C4H2S); 2J(o-13C6H5ꢀ117,119Sn)=36.3 Hz (unre-
1
for C45H36S2Si2: C, 77.5; H, 5.17%. H NMR (l ppm):
4.31 (s, 2H, CH2); 7.23–7.50 (m, 34H, o,m,p-C6H5,
3,4%-C4H2S, 4,3%-C4H2S). 13C NMR (l ppm): 34.0
(CH2); 127.1 (4,3%-C4H2S); 127.9 (m-C6H5); 129.8 (p-
C6H5); 134.1 (i-C6H5); 135.0 (3,4%-C4H2S); 136.1 (o-
C6H5); 138.6 (2,5%-C4H2S); 150.3 (5,2%-C4H2S). 29Si
NMR (l ppm): −19.2.
2.8. Synthesis of 5-trimethylstannyl-1-[(5-trimethyl-
stannyl-1H-pyrazol-1-yl)methyl]-1H-pyrazole (8)
To 2 (1.0 g, 6.75 mmol) in THF (50 ml) under
nitrogen at −78°C was added 1.6 M BuLi in hexanes
(9 ml, 14.4 mmol) and the resulting yellow solution
stirred for 2 h. Trimethyltin chloride (2.7 g, 13.5 mmol)
in THF (20 ml) was then added at 0°C and the resulting
solution stirred for 2 h. In vacuo removal of the solvent
gave a sticky white solid which was extracted with
40–60° petrol/diethyl ether (1:1) and filtered to remove
LiCl. Evaporation of the filtrate gave a white solid and
two successive recrystallisations from 40–60° petrol/di-
ethyl ether (1:1) yielded 8 as a colourless crystalline
solid (1.58 g, 49%), m.p. 88°C. Anal. Found: C, 33.1; H,
5.21; N, 11.9. Calc. for C13H24N4Sn2: C, 33.0; H, 5.11;
3
solved); J(m-13C6H5ꢀ117,119Sn)=56.2 Hz (unresolved);
2J(3,4%-13C4H2Sꢀ117,119Sn)=39.6 Hz (unresolved). 119Sn
NMR (l ppm): −137.4. 119mSn Mo¨ssbauer (mm s−1):
I.S.=1.16; Q.S.=0.00. IR (KBr, cm−1): 3061, 1480,
1428, 1383, 1332, 1302, 1259, 1074, 1022, 997, 731, 698,
657, 455, 446.
2.6. Synthesis of 2-trimethylsilyl-5-[(5-trimethyl-
silylthien-2-yl)methyl]thiophene (6)
Compound 1 (2.0 g, 11.1 mmol) in diethyl ether (100
ml) was treated with 1.6 M BuLi (15 ml, 24 mmol) at
room temperature giving a dark brown solution which
was stirred for a further 1 h. Trimethylsilyl chloride (2.4
g, 22.1 mmol) was then added via a syringe and the
resulting cream-coloured precipitate stirred for 2 h.
Filtration under nitrogen and in vacuo removal of
solvent gave a brown oil which was vacuum distilled on
a Ku¨gelrohr apparatus to give 6 as a colourless oil (1.4
g, 39%), b.p. 180°C/0.5 mmHg. Anal. Found: C, 56.6;
1
N, 11.8%. H NMR (l ppm): 0.44 (s, 18H, CH3); 6.34
(d, 4H, CH2, [J=1.6 Hz], 4,4%-C3H2N2); 7.54 (d, 2H,
[J=1.8 Hz], 3,3%-C3H2N2); 2J(C1H3ꢀ117,119Sn)=55.7,
58.4 Hz. 13C NMR (l ppm): −7.7 (CH3); 67.3 (CH2);
115.9 (4,4%-C3H2N2); 139.7 (3,3%-C3H2N2); 142.9 (5,5%-
1
2
C3H2N2); J(13CH3ꢀ117,119Sn)=364.7, 382.3 Hz; J(4,4%-
13C3H2N2ꢀ117,119Sn)=50.6
3J(3,3%-13C3H2N2ꢀ117,119Sn)=44.0 Hz (unresolved).
Hz
(unresolved);