1
54 Organometallics, Vol. 18, No. 2, 1999
Ta ble 5. X-r a y Cr ysta llogr a p h ic Da ta for 3a , 3b, 3c, a n d 5
Retbøll et al.
3
a
3b
3c
5
formula
fw
C10H10Cl2N2Ti
277.01
monoclinic
P21/n (No. 14)
yellow
0.8 × 0.6 × 0.3
10.012(2)
8.392(2)
15.033(2)
109.08(1)
1193.7(4)
4
1.541
560
11.31
2924
0.7781-1.0000
1901
137
0.037
C12H14Cl2N2Ti
305.06
monoclinic
P21/c (No. 14)
orange
0.5 × 0.5 × 0.5
9.984(2)
19.623(1)
14.5148(9)
107.103(7)
2718.1(5)
8
1.491
1248
10.01
6435
0.9239-0.9997
3431
308
0.041
C17H24Cl2N2Ti
375.20
C34H35F6N5O6S2Ti
835.69
monoclinic
P21/n (No. 14)
orange
0.8 × 0.4 × 0.05
8.892(4)
32.571(4)
12.942(3)
97.44(2)
3716(1)
4
1.493
1720
4.24
8539
0.7595-0.9952
3477
488
0.057
cryst syst
space group
cryst color
cryst dimens, mm
a, Å
monoclinic
P21/a (No. 14)
orange-red
0.5 × 0.4 × 0.2
14.941(4)
8.392(4)
16.634(4)
116.37(2)
1868(1)
4
1.334
784
7.42
4594
0.9667-1.0000
1810
199
0.052
b, Å
c, Å
â, deg
3
V, Å
Z
-
3
Dc, g cm
F(000), e
µ(Mo KR), cm
-
1
no. of unique reflns
transmission factors
no. of data used (I > 3σ(I))
no. of variables
a
R
a
Rw
0.025
2.68
0.39
0.023
1.92
0.34
0.030
2.39
0.39
0.034
2.03
0.38
b
GOF
-
3
max residual, e Å
a
R ) ∑||Fo| - |Fc||/∑|Fo|; Rw ) [∑w(|Fo| - |Fc|) /∑wFo ] ; w ) 1/σ (Fo). b GOF ) [∑w(|Fo| - |Fc|) /(Nobs - Nparms)]1/2.
2
2
1/2
2
2
which time evolution of H
removal of the solvent in vacuo, the residual solid was
recrystallized from CH Cl /hexanes to give yellow crystals of
a in 88% yield. H NMR (CDCl ): δ 8.28 (d, J ) 7.6 Hz, 2H,
2
was observed. After filtration and
Red u ctive N-N Bon d Clea va ge of 3a -c. Complex 3a
(0.0326 g, 0.118 mmol) was added to a 0.5% sodium amalgam
suspension prepared from Na (0.020 g) and Hg (4.0 g) in THF
(5 mL). The mixture quickly became dark violet, and after 3 h
the volatiles were transferred to another Schlenk tube under
2
2
1
3
3
ortho), 7.74 (t, J ) 7.6 Hz, 1H, para), 7.58 (t, J ) 7.6 Hz, 2H,
meta), 6.63 (s, 5H, Cp). IR (KBr): 1622 (m), 1593 (m), 1515
3 2 9 3
vacuum. After addition of CH (CH ) CH as internal standard
-
1
(
3
s), 1480 (s) cm . Anal. Calcd for C10
.64; N, 10.11. Found: C, 43.07; H, 3.66; N, 10.01.
P r ep a r a tion of [Cp TiCl (NNC Me -2,6)] (3b). To a
suspension of 2b (0.215 g, 0.802 mmol) in THF (10 mL) at -78
C was added BuLi (1.61 M, 0.50 mL, 0.81 mmol) and then
Cp TiCl ] (0.200 g, 0.803 mmol). After stirring at this tem-
H
10Cl
2
N
2
Ti: C, 43.36; H,
the yield of pyridine was determined by GC to be 92%.
Reductive N-N bond cleavage of 3b and 3c was performed
analogously, giving 2,6-lutidine in 70% and 99%, respectively.
Red u ctive N-N Bon d Clea va ge of 4 a n d 5. When
cobaltocene (0.0623 g, 0.329 mmol) was added to a suspension
of 4 (0.050 g, 0.066 mmol) in THF (5 mL), the color changed
to dark brown. After 24 h the volatiles were transferred under
vacuum to another Schlenk tube. The yield of 2,6-lutidine was
2
5
H
3
2
°
[
2
2
perature for 15 min, the mixture was warmed to room
temperature over 30 min and stirred for a further 2 h. The
resulting suspension was filtered, concentrated, and layered
with hexanes to give orange crystals of 3b. Yield: 57%.
3 2 9 3
determined to be 46% by GC analysis using CH (CH ) CH as
internal standard. Reductive N-N bond cleavage of 5 per-
formed analogously gave 2,6-lutidine in 42% yield.
Complex 3b could also be prepared analogously to 3a from 1a
1
and 2b in 67% yield. H NMR (CDCl
1
3
3
): δ 7.91 (t, J ) 7.6 Hz,
Red u ctive N-N Bon d Clea va ge w ith Coba ltocen e a n d
Me SiCl. Me SiCl (0.0295 g, 0.272 mmol) in THF (2 mL) was
H, para), 7.55 (d, J ) 7.6 Hz, 2H, meta), 6.59 (s, 5H, Cp),
3
3
-
1
.00 (s, 6H, Me). IR (KBr): 1628 (s), 1561 (m), 1491 (s) cm
Ti: C, 47.25; H, 4.63; N, 9.18.
Found: C, 47.27; H, 4.79; N: 9.15.
P r ep a r a tion of [Cp *TiCl (NNC
compound was prepared analogously to 3a from 1b and 2b as
.
added slowly over 2 h to a THF (5 mL) solution containing
cobaltocene (0.077 g, 0.407 mmol) and 3a (0.0362 g, 0.131
mmol). After 20 h the volatiles were transferred under vacuum
to another Schlenk tube. The yield of pyridine was determined
2 2
Anal. Calcd for C12H14Cl N
2
5 3 2
H Me -2,6)] (3c). This
3 2 9 3
to be 55% by GC analysis using CH (CH ) CH as internal
1
orange-red crystals in 92% yield. H NMR (CDCl
3
): δ 7.33 (t,
standard. Reductive N-N bond cleavage of 3b and 3c per-
formed analogously gave 2,6-lutidine in 80% and 91% yield,
respectively.
J ) 7.6 Hz, 1H, para), 7.22 (d, J ) 7.6 Hz, 2H, meta), 2.73 (s,
6
H, Me), 2.07 (s, 15H, Cp*). IR (KBr): 1626 (s), 1561 (s) cm-1
Anal. Calcd for C17
.
H
24Cl
2
N
2
Ti: C, 54.42; H, 6.45; N, 7.47.
X-r a y Diffr a ction Stu d ies. Single crystals suitable for
X-ray analysis were sealed in glass capillaries under nitrogen
and mounted on a Rigaku AFC7R four-circle diffractometer
equipped with a graphite-monochromatized Mo KR source (λ
) 0.7107 Å). Orientation matrixes and unit cell parameters
were determined by least-squares refinement of 25 machine-
centered reflections with 37.5° < 2θ < 39.8° for 3a , 39.5° < 2θ
< 40.0° for 3b, 36.4° < 2θ < 40.0° for 3c, and 36.7° < 2θ <
39.8° for 5. The data collection was performed at room
temperature using the ω-2θ scan technique for 3a , 3b, and
Found: C, 54.21; H, 6.58; N, 7.43.
P r epar ation of [Cp*Ti(OTf)(NNC
5
H
3
Me
2
-2,6)(bpy)][OTf]
(
4). THF (6 mL) was added to powders of 3c (0.0806 g, 0.215
mmol), AgOTf (0.110 g, 0.428 mmol), and 2,2′-bipyridine (0.100
g, 0.640 mmol). After stirring for 4 h, the resulting suspension
was filtered, concentrated, and layered with hexanes to give
orange crystals of 4. Yield: 83%. Anal. Calcd for C29
Ti: C, 45.92; H, 4.25; N, 7.39. Found: C, 45.78; H, 4.35; N,
.43.
P r ep a r a tion of [Cp *Ti(NNC
5). THF (10 mL) was added to powders of 3c (0.0747 g, 0.199
32 6 4 6 2
H F N O S -
7
-
1
5
H
3
Me
2
-2,6)(ter p y)][OTf]
2
3c and the ω scan technique for 5 at a rate of 32 deg min (5°
< 2θ < 55°). Intensity data were corrected for Lorentz-
polarization effects and for absorption (ψ scans). For crystals
of 3a and 5, no significant decay was observed for respective
three standard reflections monitored every 150 reflections
during the data collection. For crystals of 3b and 3c, slight
decay (3b, 1.73%; 3c, 4.35%) was observed during the data
collection, and a correction for decay was applied. Details of
(
mmol), AgOTf (0.1275 g, 0.496 mmol), and 2,2′:6′,2′′-terpyri-
dine (0.186 g, 0.797 mmol), and the mixture was stirred for 4
h. The resulting suspension was filtered, concentrated, and
layered with hexanes to give orange needles of 5. Yield: 82%.
Anal. Calcd for C34
35 6 5 6 2
H F N O S Ti: C, 48.87; H, 4.22; N, 8.38.
Found: C, 48.63; H, 4.04; N, 8.28.
Retb?ll, Mikael
