178
P. Jutzi, L.O. Schebaum / Journal of Organometallic Chemistry 654 (2002) 176ꢂ179
/
500.1 MHz; 13C{1H} 125.8 MHz; 71Ga{1H} 91.5 MHz).
Chemical shifts are reported in ppm and were referenced
to the solvent resonances as internal standard. IR data
were collected using a Bruker Vektor 22-FT spectro-
meter. Mass spectrometry was performed using a VG
Autospec spectrometer. Only characteristic fragments
and isotopes of the highest abundance are listed.
benzene was sonicated for 12 h at 50 8C. To the
resulting pale green ‘GaI’ an equimolar amount of the
corresponding potassium cyclopentadienide (Cp*K:
5.00 g, 28 mmol; Cp?K: 5.40 g, 28 mmol) was added.
The reaction suspension was then stirred for 48 h.
During this time the color of the benzene solution
turned to yellow, while a light grey precipitate was
formed. After filtration and extraction of the remaining
grayish solid with 20 ml of benzene, the solvent was
removed from the combined yellow solutions. The
remaining oil was distilled at 80 8C (8 Torr) to give
the corresponding gallium cyclopentadienide (Cp*Ga 1:
3.53 g, 17 mmol; Cp?Ga 2: 3.72 g, 17 mmol) as a light
yellow liquid in about 60% yield.
3.2. Preparation of Cp*Ga in toluene
A mixture of (2.00 g, 28 mmol) Ga particles (dia-
meter: 1 mm) and I2 (3.64 g, 14 mmol) in 40 ml of
toluene was sonicated for 12 h at 50 8C. To the resulting
pale green ‘GaI’ an equimolar amount of Cp*K (5.00 g,
28 mmol) was added. The reaction suspension was then
stirred for 48 h. During this time the color of the toluene
solution turned to yellow, while a light grey precipitate
was formed. After filtration and extraction of the
remaining grayish solid with 20 ml of toluene, the
solvent was removed from the combined yellow solu-
tions. The remaining oily reaction product contains
(benzyl)pentamethylcyclopentadiene (0.43 g, 2 mmol)
and Cp*Ga. Distillation at 80 8C (8 Torr) gives 3.06 g
Cp*Ga (15 mmol) as a light yellow liquid in 52% yield.
Analytical data for 1 correspond to those reported in
the literature [3]. Data for (benzyl)pentamethylcyclo-
pentadiene [18]: 1H-NMR (C6D6): d 0.98 (s, 3H,
C6H5CH2(C5Me5)), 1.55 (s, 6 H, C6H5CH2(C5Me5)),
1.75 (s, 6 H, C6H5CH2(C5Me5)), 2.64 (s, 2 H,
C6H5CH2(C5Me5)), 7.03 (m, 5 H, C6H5CH2(C5Me5)).
13C-NMR (C6D6): d 10.51, 10.93, 22.03, 41.72, 57.10,
126.05, 127.50, 128.87, 134.85, 138.96, 139.46. MS (EI,
70 eV) [m/z] (rel. int.): 226 [Mꢃ (53)], 203 [Cp*ꢃ (100)],
1
Data for 2: b.p. 80 8C (8 Torr). H-NMR (C6D6):
3
1.04 (t, JHH
dꢀ
/
ꢀ7.5 Hz, 3 H, (CH3CH2)Me4C5), 1.92
/
and 1.93 (s, 12 H, (CH3CH2)Me4C5), 2.38 (q, 3JHH
Hz, 2 H, (CH3CH2)Me4C5). 13C-NMR (C6D6): dꢀ
((CH3CH2)Me4C5), 9.9 ((CH3CH2)Me4C5), 17.6
ꢀ/7.5
/9.7
((CH3CH2)Me4C5), 18.3 ((CH3CH2)Me4C5), 113.0 and
113.2 ((CH3CH2)Me4C5), 121.4 ((CH3CH2)Me4C5Ã
Ethylà 650.7 (v1/2 1.7
C). 71Ga-NMR (C6D6): dꢄ
kHz). MS (EI, 70 eV) [m/z] (rel. int.): 218 [Mꢃ (45)],
/
/
/
ꢀ
/
203 [Mꢃ Ã
(100)], 119 [Cp?ꢃ
(43)], 91 [Cp?ꢃ
2 MeÃ
Calc. for C11H17Ga (Mꢀ
/
Me (26)], 150 [Cp?Hꢃ (50)], 135, [Cp?ꢃ
Ã
/
CH2
Ã
/
2 Me (62)], 105 [Cp?ꢃ
Ã
/
2 MeÃ
/CH2
Ã
/
/
2 CH2 (53)], 69 (Gaꢃ (65)]. Anal.
/
218.98 g molꢄ1): C, 60.34; H,
7.83. Found: C, 60.57; H, 7.91%.
Acknowledgements
The support of this work by the Deutsche For-
schungsgemeinschaft, the Universitat Bielefeld, and the
121, [Cp*ꢃ Ã
/
CH2 (41)], 119 [Cp*ꢃ Ã
/
MeÃ/H (31)], 105
¨
[Cp*ꢃ Ã2 Me (24)], 69 (Gaꢃ (9)].
/
Fond der Chemischen Industrie is gratefully acknowl-
edged.
3.3. Isolation of C6H5CH2I
A mixture of (2.00 g, 28 mmol) Ga particles (dia-
meter: 1 mm) and I2 (3.64 g, 14 mmol) in 40 ml of
toluene was sonicated for 12 h at 50 8C. The resulting
suspension was filtrated. After removing all volatile
components a colorless powder was isolated, which was
analyzed to be C6H5CH2I, (0.43 g, 2 mmol).
Data for C6H5CH2I [19]: m.p. 27 8C. 1H-NMR
(C6D6): d 3.96 (s, 2H, C6H5CH2I), 6.89 (m, 5 H,
C6H5CH2I). 13C-NMR (C6D6): d 33.4 (C6H5CH2I),
128.33/128.8/129.2/138.1 (C6H5CH2I). IR (cmꢄ1, KBr):
References
[1] Reviews concerning the chemistry of low-valent group 13-
elements: (a) C. Dohmeier, D. Loos, H. Schnockel, Angew.
¨
Chem. Int. Ed. Engl. 35 (1996) 129;
(b) R. Murugavel, V. Chandrasekhar, Angew. Chem. Int. Ed. 38
(1999) 1211;
(c) G. Linti, H. Schnockel, Coord. Chem. Rev. 206ꢂ207 (2000)
285.
[2] (a) M. Tacke, H. Kreienkamp, L. Plaggenborg, H. Schnockel, Z.
¨
/
¨
Anorg. Allg. Chem. 604 (1991) 35;
(b) D. Loos, H. Schnockel, J. Organomet. Chem. 463 (1993) 37;
nꢀ3023 (w), 3011 (w), 2965 (w), 1490 (m), 1453 (m),
/
¨
(c) D. Loos, E. Baum, A. Ecker, H. Schnockel, Angew. Chem. Int.
¨
1266 (vs), 1221 (s), 1062 (m), 1043 (m), 910 (w), 821 (w),
763 (s), 694 (vs).
Ed. 36 (1997) 860;
(d) A. Haaland, L.G. Martinsen, H.V. Volden, D. Loos, H.
3.4. Preparation of CpxGa in benzene
Schnockel, Acta Chem. Scand. 48 (1994) 172.
¨
[3] P. Jutzi, B. Neumann, G. Reumann, H.-G. Stammler, Organo-
metallics 17 (1998) 1305.
A mixture of (2.00 g, 28 mmol) Ga particles (dia-
meter: 1 mm) and I2 (3.64 g, 14 mmol) in 40 ml of
[4] (a) P. Jutzi, B. Neumann, L.O. Schebaum, A. Stammler, H.-G.
Stammler, Organometallics 18 (1999) 4462;