Six-coordinate organotin(IV) complexes formed using the Kl?ui ligands; [CpCo{P(OR′)2O}3]SnR3 - nCln

Article abstract of DOI:10.1016/j.jorganchem.2006.02.010

The complexes [CpCo{P(OR′)₂O}₃]SnR_{3 - n}Cl_n [R′ = Me, Et; R = Ph, Me] are readily prepared from the corresponding organotin chloride and the sodium salt of the Kl?ui ligands. The X-ray crystal structures of the full series are reported for R = Ph, n = 0-3, and these show that they are all six-coordinate, including the Ph₃Sn derivative which is the first example of a SnC₃O₃ coordination sphere. ¹H, ¹³C, ³¹P and ¹¹⁹Sn NMR spectra are reported, and interpreted in terms of significant second-order effects and fluxional processes.

Full text of DOI:10.1016/j.jorganchem.2006.02.010

Journal of Organometallic Chemistry 691 (2006) 2757–2766
www.elsevier.com/locate/jorganchem
Six-coordinate organotin(IV) complexes formed using the Kl a¨ ui
0
ligands; [CpCo{P(OR ) O} ]SnR Cl
2
3
3 ꢀ n
n
*
Nicholas C. Lloyd, Brian K. Nicholson , Alistair L. Wilkins
Department of Chemistry, University of Waikato, Private Bag 3105, Hamilton, New Zealand
Received 14 December 2005; received in revised form 7 February 2006; accepted 9 February 2006
Available online 14 February 2006
Abstract
0
0
n
[R = Me, Et; R = Ph, Me] are readily prepared from the corresponding organotin
The complexes [CpCo{P(OR )
2
O}
3
]SnR3 ꢀ nCl
chloride and the sodium salt of the Kl a¨ ui ligands. The X-ray crystal structures of the full series are reported for R = Ph, n = 0–3, and these
show that they are all six-coordinate, including the Ph Sn derivative which is the first example of a SnC O coordination sphere. H, C,
3 3 3
P and Sn NMR spectra are reported, and interpreted in terms of significant second-order effects and fluxional processes.
1
13
3
1
119
ꢀ
2006 Elsevier B.V. All rights reserved.
Keywords: Tin; Kl a¨ ui ligands; NMR spectra; X-ray structure; Six coordination
1
. Introduction
H
B
_
The coordination chemistry of organo–tin(IV) is well
Co
P(OR)2
O
developed [1]. As is entirely predictable, for R SnX
R = alkyl, aryl; X = Cl, Br, etc.), the tendency towards
N
N
n
4 ꢀn
N
N
N
N
(RO) P
2
P(OR)2
(
increased coordination number decreases as the number
O
O
of R groups increases. Hence, while RSnX readily forms
3
six-coordinate complexes with a wide range of Lewis bases,
Sn
Me
(
2) L R = Me
corresponding R SnX rarely forms analogous hexa-
3
LEt R = Et
coordinate species [2]. There appear to be only five struc-
Me
Me
Me
(1)
turally-characterised six-coordinate tin complexes which
+
incorporate a R Sn group, all involving strongly chelating
3
or pincer-type ligands [3]. The first of these to be reported
was the reasonably-stable Me Sn[pz BH] (1) [4], and sev-
3
3
An analogous type of mono-negative tridentate ligand
which encourages strong coordination are the Kl a¨ ui ligands
eral subsequent studies described related pyrazolyl-borate
complexes [5]. These included Ph Sn[pz BH] which was
3
3
2
[9]. These have been found to give many novel complexes
however found to be too unstable for structural character-
isation [6,7]. The higher coordination numbers found for
these compounds are a consequence of the strong tendency
for the tripodal Trofimenko-type pyrazolyl-borate ligands
to be tridentate [8].
of the d- and f-block elements. In contrast, there have been
few studies in which 2 has been used to form derivatives of
the p-block elements. For Group 14 these have been
R
2
restricted to L M ðM ¼ Si; Sn; PbÞ [10] and to recently
Et
described inorganic four-coordinate Ge(II) and six-coordi-
nate Ge(IV) derivatives of the type L GeCl and
Et
*
L Ge(N ) , respectively [11]. The only organometallic
Corresponding author. Fax: +64 7 838 4219.
3 3
Me
E-mail address: b.nicholson@waikato.ac.nz (B.K. Nicholson).
p-block example of which we are aware is Me ClSnL [12].
2
0
022-328X/$ - see front matter ꢀ 2006 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2006.02.010

2758
N.C. Lloyd et al. / Journal of Organometallic Chemistry 691 (2006) 2757–2766
We now report the preparation of the series
a round-bottomed flask. A solution of Ph SnCl (0.405 g,
3
R
R
Me Cl
SnL (R = Me) and Ph Cl
SnL (R = Me,
1.05 mmol) in CH Cl (ca. 5 mL) was added in one por-
n
3 ꢀ n
n
3 ꢀ n
2
2
Et) together with selected structures and spectroscopic
properties. This includes the structure of Ph SnL , which
tion with stirring, and the mixture was stirred for
30 min. The cloudy mixture was filtered through a small
column of Florisil and the solvent removed from the
yellow solution by rotary evaporation. The residue was
recrystallised from CH Cl /petroleum spirits at ꢀ20 ꢁC
Me
3
is the first example for a Sn(IV) compound with a SnC O
3
3
coordination sphere. Some aspects of this work have been
briefly communicated elsewhere [13].
2
2
Me
giving yellow crystals of Ph SnL
(0.64 g, 76%). Anal.
3
2
. Experimental
Calc. for C H CoO P Sn: C, 43.48; H, 4.78. Found:
29 38 9 3
1
C, 43.54; H, 4.53%. H NMR: d 3.51 (CH , vq),
3
2
.1. General methods
5.10 (Cp, s), 7.24 (m, p-Ph, m), 7.83 (o-Ph, d,
3
3
J = 7.4 Hz, tin satellites
57 Hz); C NMR: d 52.4 (CH , vq,
89.1 (Cp, s), 126.5 (p-Ph, s, tin satellites
J
119
1
¼ 69 Hz,
J
P–13C
117
1
¼
Sn– H
Sn– H
1
3
2
The new compounds were generally stable in air, but
J
31
¼ 3 Hz),
3
reactions involving organotin chlorides were carried out
under dry nitrogen conditions, using purified solvents.
4
J
119
Sn–13C; 117Sn–13
ðavÞ ¼ 15:6 Hz), 126.8 (m-Ph, s, tin satel-
C
1
13
1
31
1
119
1
3
H, C{ H}, P{ H} and Sn{ H} NMR spectroscopy
was performed on a Bruker Avance series DRX 300 or
00 MHz machine at 303 K in CDCl unless otherwise
lite
satellite
3
J
119
Sn–13C; 117Sn–13
ðavÞ ¼ 64:8 Hz), 136.9 (o-Ph, s, tin
C
2
J
119Sn–13
C; 117Sn–13
ðavÞ ¼ 49:5 Hz), 154.9 (i-Ph, q,
119
C
1
4
J
J
31P–13
¼ 3:5 Hz, tin satellites
J
119
13 ¼ 746 Hz,
3
C
Sn–
C
3
1
1
31
noted. P spectra were referenced to orthophosphoric
acid and
variable temperature
117Sn–13
¼ 720 Hz); P NMR: d 117 (s);
Sn NMR:
C
1
19
2
Sn spectra were referenced to SnMe . For
d ꢀ408 (q, J31 119 ¼ 82 Hz).
4
P– Sn
1
19
Sn NMR corrections were
applied for shifts in the signal, arising from variations
in temperature. Resolution of spectra was, on average,
Me
.4. Preparation of Ph ClSnL (4)
2
2
1
13
31
119
H, 0.09 Hz, C, 0.55 Hz, P, 1.2 Hz,
Sn, 1.2 Hz.
Using the same method, Ph SnCl
(0.361 g,
2
2
Data processing and collection used the XWIN NMR
V3.1 software suite. Where necessary, resolution enhance-
ment was used, to allow confused and overlapping pat-
terns to be seen. This was done by either altering the
line-broadening factor (LB) or by setting a negative LB
value (dependent on the nucleus in question: ꢀ1 Hz for
Me
1
.05 mmol) was reacted with NaL (0.500 g, 1.05 mmol)
Me
in CH Cl (5 mL) to give yellow crystals of Ph ClSnL
2
2
2
after purification and recrystallisation from CH Cl and
petroleum spirits (0.49 g, 62%). Anal. Calc. for C H -
2
2
2
3
33
ClCoO P Sn: C, 36.37; H 4.38. Found: C, 36.92, H,
9
3
1
3
4
3
3
.46%. H NMR: d 3.44 (CH , t,
J
31
1
¼ 5:3 Hz),
1
13
31
119
3
P– H
H and C, ranging to ꢀ20 Hz for P and
Sn due
3
.52 (CH3, d,
J
31
1
¼ 10:6 Hz), 3.85 (CH , t,
P– H
3
to the natural line width) and a GB value of 0.3 Hz.
Scalar coupling constants were measured directly by
observation from the spectra without simulation of sec-
ond-order effects.
J
31
1
¼ 5:4 Hz), 5.12 (Cp, s), 7.21 (m, p-Ph, m), 7.82
P– H
2
(
2
o-Ph, d, J = 6.6 Hz, tin satellites
J
119
1
¼ 94:2 Hz,
Sn– H
13
J
117
1
¼ 79:4 Hz); C NMR: d 52.6 (CH , br m),
Sn– H
3
5
3.7 (CH , br t, J = 4.3 Hz), 89.4 (Cp, s), 127.2 (m-Ph,
3
The organo–tin compounds were purchased from
3
s, tin satellite J
s, tin satellite J
tin satellite J
119Sn–13C; 117Sn–13
ðavÞ ¼ 90 Hz), 127.2 (p-Ph,
Me
Et
C
Aldrich, while the Kl a¨ ui ligands NaL and NaL were
from Strem.
4
119Sn–13
C; 117Sn–13
ðavÞ ¼ 18 Hz), 135.3 (o-Ph, s,
C
2
119Sn–13
C; 117Sn–13
ðavÞ ¼ 62 Hz), 154.3 (i-Ph, q,
119
C
3
1
J
J
ꢀ
31P–13
¼
3:5 Hz, tin satellites
J
119
13 ¼ 1047 Hz,
C
Sn–
C
2
.2. Preparation of PhMeSnCl (cf. Ref. [14])
2
31
1
117Sn–13
¼ 997 Hz); P NMR d 119 (m). Sn NMR: d
C
2
491 (d of t, J31 119 ¼ 94; 62 Hz).
P– Sn
PhSnCl3 (3.02 g, 10 mmol) in a Schlenk flask under
nitrogen was cooled to 0 ꢁC in an ice bath. SnMe4
1.79 g, 10 mmol) was added dropwise, with stirring. After
Me
2.5. Preparation of PhCl SnL (5)
2
(
addition was complete, stirring was continued for half an
hour. The mixture was pumped under vacuum at room
Using the same method, PhSnCl
(0.307 g, 1.05 mmol)
(0.500 g, 1.05 mmol) in CH Cl
(0.44 g,
Sn: C, 28.44, H,
3.93. Found: C, 28.16; H, 3.97%. H NMR: d 3.47 (CH
m), 3.75 (CH , m), 3.82 (CH , m), 5.12 (Cp, s), 7.25 (m,
3
Me
temperature for several hours to remove the Me SnCl by-
was reacted with NaL
(5 ml) to give yellow crystals of PhCl
58%). Anal. Calc. for C17 CoO
2
2
3
Me
product. The residue (2.74 g, 97%) was checked by GC–
SnL
2
1
MS to establish purity, giving >95% MePhSnCl .
H
H
28Cl
2
P
9 3
2
1
3
1
NMR: d 1.35 (CH , s), 7.68–7.52 (C H , m); C NMR: d
,
3
3
6
5
4
.80 (CH , s), 129.6 (m-Ph, s), 131.7 (p-Ph, s), 134.6 (o-
3
3
3
1
19
Ph, s), 138.8 (i-Ph, s); Sn: d 55.1.
p-Ph, m), 7.83 (o-Ph, d, J = 6.6 Hz, tin satellites
3
3
13
J
119
1
¼ 138:6 Hz, J117
1
¼ 130:4 Hz); C NMR: d
Sn– H
Sn– H
Me
.3. Preparation of Ph SnL (3)
2
52.8 (CH
3
, m), 53.7 (CH
3
, m), 54.0 (CH
3
, m), 89.7 (Cp,
3
3
s,), 127.6 (m-Ph, s, J
119Sn–13
C; 117Sn–13
C; 117Sn–13
ðavÞ ¼ 146 Hz), 128.2
C
Me
4
A solution of NaL
(0.500 g, 1.05 mmol) was dis-
(p-Ph, s, tin satellite J
119Sn–13
ðavÞ ¼ 28 Hz), 133.8
C
2
solved in the minimum amount of CH Cl (ca. 5 mL) in
(o-Ph, s, tin satellite J
119Sn–13C; 117Sn–13
ðavÞ ¼ 78 Hz), 153.5
2
2
C

N.C. Lloyd et al. / Journal of Organometallic Chemistry 691 (2006) 2757–2766
2759
1
31
Et
2.11. Preparation of Ph SnL (11)
3
(
i-Ph, m, tin satellite J
119Sn–13
C; 117Sn–13
ðavÞ ¼ 1720 Hz);
P
C
1
19
NMR: d 117 (br, s); Sn NMR: d ꢀ569 (m).
Me
Using the same method, Ph SnCl (0.345 g, 0.896 mmol)
3
Et
2
.6. Preparation of Cl SnL (6)
was reacted with NaL (0.500 g, 0.896 mmol) in CH Cl
2
3
2
Et
(5 mL) to give yellow crystals of Ph SnL (0.53 g, 67%).
3
Similarly, SnCl (0.1642 g, 0.63 mmol) was reacted with
Calcd for C H CoO P Sn: C, 47.48; H, 5.69. Found: C,
35 50 9 3
4
Me
1
NaL (0.300 g, 0.63 mmol) in CH Cl (5 ml) to give yel-
47.48, H, 5.59%. H NMR: d 1.17 (CH , t, J = 7.1 Hz),
2
2
3
Me
low crystals of Cl SnL
(0.16 g, 38%). Anal. Calc. for
3.92 (CH , m), 5.07 (Cp, s), 7.25 (m, p-Ph, m), 7.80 (o-
3
2
3
C H Cl CoO P Sn: C, 19.54, H, 3.43. Found: C, 19.68,
Ph, d, J = 6.6 Hz, tin satellites
J
119
1
¼ 68 Hz,
1
1
23
3
9
3
Sn– H
1
3
3
13
3
H, 3.34%. H NMR: d 3.80 (CH , vq, J31
.22 (Cp, s). C NMR: d 54.0 (CH , vq,
:3 Hz), 89.9 (Cp, s). P NMR: d 121 (s). Sn NMR: d
661 (br, s).
1
¼ 3:8 Hz),
J
117
1
¼ 54 Hz); C NMR: d 16.5 (CH , vq, J31 13
3
P– H
Sn– H
3
P– C
1
3
2
2
5
3
J
31
13
¼
¼ 1:9 Hz), 60.9 (CH , vq,
J
31P–13
C
¼ 3:1 Hz), 89.5 (Cp,
3
P–
C
2
3
1
119
4
s), 126.3 (p-Ph, s, tin satellite
J
119
13
117
13 ðavÞ
Sn– C
Sn– C;
3
ꢀ
¼ 13 Hz), 126.6 (m-Ph, s, tin satellite J
119Sn–13
¼ 66 Hz,
C
3
J
J
J
117 13 J ¼ 64 Hz), 136.9 (o-Ph, s, tin satellite
2
117
av
Sn–
C
Me
.7. Attempted preparation of Me SnL (7)
2
2
119Sn–13C;
13 ðavÞ
J
¼ 49 Hz),
155.4
(i-Ph,
q,
3
Sn–
C
3
1
31P–13
¼ 3:6 Hz,
tin satellite
J
119Sn–13C
119
¼ 750 Hz,
C
3
1
Using the same method, Me SnCl (0.209 g, 1.05 mmol)
J
117Sn–13
¼ 717 Hz); P NMR: d 114 (s);
Sn NMR: d
3
C
Me
2
with NaL (0.500 g, 1.05 mmol) in CH Cl (5 ml) gave yel-
ꢀ413 (q, J119 31 ¼ 82 Hz).
2
2
Sn– P
low crystals of a complex mixture of products, apparently
Me
Me
Me
Et
2.12. Preparation of Ph ClSnL (12)
2
Me ClSnL , MeCl SnL and NaL (see Section 3).
2
2
Me
.8. Preparation of Me ClSnL (8)
2
Similarly, Ph SnCl (0.308 g, 0.896 mmol) was reacted
2 2
2
Et
with NaL (0.500 g, 0.896 mmol) in CH Cl (5 mL) to give
2
2
Et
Similarly, Me SnCl (0.2307 g, 1.05 mmol) was reacted
yellow crystals (from CDCl ) of Ph ClSnL (0.18 g, 24%).
3 2
2
2
Me
with NaL (0.500 g, 1.05 mmol) in CH Cl (5 ml) to give
yellow crystals of Me ClSnL (0.40 g, 60%). Anal. Calc.
Anal. Calc. for C H ClCoO P Sn Æ 2CHCl : C, 34.33; H,
29 45 9 3 3
2
2
Me
1
4.55. Found: C, 34.92; 5.03%. H NMR: d 1.08 (CH , t,
2
3
for C H ClCoO P Sn: C, 24.59, H, 3.66. Found: C,
J = 7.1 Hz), 1.14 (CH , t, J = 7.1 Hz), 1.31 (CH , t,
J = 7.1 Hz), 3.85 (CH , m), 4.27 (CH , m), 5.07 (Cp, s),
2 2
1
3
29
9
3
1
3
3
2
J
4.95; H, 4.50%. H NMR: d 0.43 (CH –Sn), s,
3
3
2
119
1
¼ 76 Hz, 3.62 (CH –O, pseudo q,
J
31
1
¼
7.20 (m, p-Ph, m), 7.81 (o-Ph, d, J = 7.0 Hz,
Sn– H
3
P– H
1
3
3
3
13
3
:4 Hz), 5.03 (Cp, s). C NMR: d 14.0 (CH –Sn, q,
31P–13
J
119
1
¼ 92 Hz, J117
1
¼ 80 Hz). C NMR: d 16.3
3
Sn– H
Sn– H
3
1
J
¼ 3:3 Hz, tin satellites
119
J
119Sn–13
¼ 713 Hz,
(CH , m), 16.6 (CH , t, J = 2.9 Hz), 61.3 (CH , m), 62.2
C
C
3 3 2
1
J
117Sn–13
¼ 682 Hz), 52.5 (CH –O, br, s), 89.3 (Cp, s);
(CH , t, J = 4.5 Hz), 89.6 (Cp, s), 127.0 (p-Ph, s, tin satel-
2
C
3
3
1
4
P NMR: d 117 (br, s).
Sn NMR: d ꢀ340 (q,
lite J
119Sn–13
C; 117Sn–13
ðavÞ ¼ 18 Hz), 126.9 (m-Ph, s, tin satel-
C
2
3
3
J
31P–119
¼ 88 Hz).
lite J
119Sn–13
¼ 91 Hz, J117 13 ðavÞ ¼ 88 Hz), 135.3 (o-Ph,
Sn
C
Sn–
C
2
s, tin satellite
J
119
Sn– C; 117Sn–13
13
ðavÞ ¼ 61 Hz), 154.8 (i-Ph,
C
Me
.9. Preparation of MeCl SnL (9)
3
1
2
q,
1
J
31P–13
¼ 3:5 Hz, tin satellites
J
119
13 ¼ 1044 Hz,
2
C
Sn–
C
31
119
J
117Sn–13
¼ 1004 Hz). P NMR: d 116 (m).
Sn NMR:
C
Me
2
Similarly, MeSnCl3 (0.252 g, 1.05 mmol) and NaL
d ꢀ495 (d of t, J119
Sn–31P
¼ 92; 62 Hz).
Et
(
0.500 g, 1.05 mmol) in CH Cl (5 ml) gave yellow crystals
2 2
Me
of MeCl SnL
(0.55 g, 80%). Anal. Calc. for
2.13. Preparation of PhCl SnL (13)
2
2
C H Cl CoO P Sn: C, 21.98, H, 3.97. Found: C, 22.04,
1
2
26
2
9 3
1
H, 3.97%. H NMR: d 0.98 (Me–Sn, s, tin satellites
Similarly, PhSnCl (0.345 g, 0.896 mmol) was reacted
3
2
2
Et
J
119Sn–13
¼ 135 Hz,
J
117Sn–13
¼ 131 Hz), 3.63 (CH –O,
with NaL (0.500 g, 0.896 mmol) in CH Cl (5 mL) to give
C
C
3
2
2
1
3
Et
m), 3.75 (CH –O, m), 5.13 (Cp, s). C NMR: d 19.2
CH –Sn, pseudo q,
yellow crystals of PhCl SnL (0.57 g, 79%). Anal. Calc. for
3
2
3
(
1
J
31P–13
¼ 3:5 Hz, tin satellites
C H Cl CoO P Sn.CHCl : C, 32.13, H, 4.53. Found C,
3
C
24 40
2
9
3
3
1
1
J
119Sn–13
¼ 1274 Hz, J
117Sn–13
¼ 1218 Hz), 52.6 (CH –O,
32.71, H, 4.80. H NMR: d 1.08 (CH , t, J = 7.1 Hz),
C
C
3
3
3
1
m), 53.5 (CH –O, m), 54.0 (CH –O, m), 89.7 (Cp, s);
P
1.27 (CH , t, J = 7.0 Hz), 1.29 (CH , t, J = 7.0 Hz), 3.85
3
3
3
3
1
19
NMR: d 119 (br, s); Sn NMR: d ꢀ509 (m).
Me
(CH , m), 4.25 (CH , m), 5.09 (Cp, s), 7.24 (m, p-Ph, m),
2 2
3
7
J
(
.81 (o-Ph, d, J = 7.1 Hz, tin satellites J119
1
¼ 142 Hz,
Sn– H
3
13
2
.10. Preparation of PhMeClSnL (10)
117
1
¼ 133 Hz); C NMR: d 16.3 (CH , m), 16.5
Sn– H
3
CH3, m), 61.8 (CH2, m), 62.5 (CH2, m), 62.9
Me
As above, PhMeSnCl (0.237 g, 0.84 mmol) with NaL
(CH , m), 89.9 (Cp, s), 128.0 (p-Ph, s, tin satellite
2
2
4
(
0.400 g, 0.84 mmol) in CH Cl (5 ml) gave a yellow solid.
Several recrystallizations were attempted, but were not suc-
cessful because of rearrangement reactions. This com-
J
J
119Sn–13C; 117Sn–13
C
ðavÞ ¼ 28 Hz), 127.3 (m-Ph, s, tin satellite
2
2
3
3
119Sn–13
¼ 146 Hz,
J
117
13 ðavÞ ¼ 139 Hz), 133.7 (o-Ph,
31
C
Sn–
C
2
s, tin satellite
m, tin satellites
J
119
Sn–13C; 117Sn–13
ðavÞ ¼ 77 Hz), 153.8 (i-Ph,
C
1
19
1
pound was only characterised by its
see discussion).
Sn NMR shift
J
119Sn–13
C; 117Sn–
13 ðavÞ ¼ 1729 Hz);
P
C
1
19
(
NMR: d 116 (s); Sn NMR: d ꢀ570 (m).

2760
N.C. Lloyd et al. / Journal of Organometallic Chemistry 691 (2006) 2757–2766
2
.14. X-ray crystallography
Data were collected on a Bruker SMART CCD dif-
Co
P(OR)2
O
fractometer using standard procedures. They were solved
2
(RO) P
2
P(OR)2
O
by direct methods and refined (on F ) using the SHELX
o
programs [15] running under WINGX [16]. Crystal data
O
and refinement details are in Table 1. Special details
Me
for each: Ph SnL (3) crystallized with two independent
3
Me
molecules in the asymmetric unit; Cl SnL
(6) was
Sn
3
located on a mirror plane which led to disorder involving
the Cp ring and the Me groups so hydrogen atoms were
1
R3
R
R2
not included in the refinement and the precision of the
Me
determination was reduced; PhCl SnL
(5) crystallized
1
2
3
2
3
4
5
6
7
8
9
1
1
1
1
R = Me R = R = R =Ph
with a molecule of CH Cl in the lattice but was other-
1
2
3
2
2
R = Me R = R = Ph R = Cl
Et
wise straightforward; Ph ClSnL (12) also had disorder,
2
1
2
3
R = Me R = Ph R = R = Cl
involving the CH portion of the the Et groups but this
2
1
2
3
R = Me R = R = R = Cl
was readily modelled. The structures are illustrated in
Figs. 1–4 with selected bond parameters included in the
captions.
1
2
3
R = Me R = R = R = Me
1
2
3
R = Me R = R = Me R = Cl
1
2
3
R = Me R = Me R = R = Cl
1
2
3
0 R = Me R = Me R = Ph R = Cl
3
. Results and discussion
1
2
3
1
R = Et R = R = R = Ph
1
2
3
2 R = Et R = R = Ph R = Cl
3
.1. Preparation of the complexes
1
2
3
3 R = Et R = Ph R = R =Cl
Synthesis of the new complexes 3–13 was generally
Recrystallisation generally yielded pure, air-stable com-
pounds in good yields and these were characterized by ele-
mental analysis and NMR spectroscopy. The structures of
3, 5, 6 and 12 were also determined. No indication of ligand
straightforward, by combining equal amounts of the
R
appropriate organotin chloride with NaL in CH Cl
2
2
(
Eq. (1)).
rearrangements equivalent to that observed for reactions of
R
R
Et
R3 SnCl þ NaL ! R SnCl L þ NaCl
ð1Þ
NaL with ZrCl was seen with the tin halides [17].
ꢀn
n
3ꢀn
nꢀ1
4
Table 1
Crystal data and refinement details
Me
Me
Et
ClSnL (12)
Me
Cl
3
SnL Æ CH
2
Cl
2
(6) Æ CH
2
Cl
2
PhCl
2
SnL Æ CH
2
Cl
2
2
(5) Æ CH Cl
2
Ph
2
Ph
3
SnL (3)
Formula
M
C
761.10
203
12
H
25Cl
5
CoO
9
P
3
Sn
C
802.75
168
18
H
30Cl CoO
4
9
P
3
Sn
C
843.63
168
29
H
45ClCoO
9
P
3
Sn
C
801.12
200
29
H
9 3
38CoO P Sn
r
T (K)
Crystal system
Space group
Orthorhombic
Pnma
Triclinic
Triclinic
Monoclinic
P2 /c
1
ꢀ
ꢀ
P1
P1
˚
a (A)
17.6545(2)
12.2563(2)
12.1295(2)
90
90
90
2624.57(7)
4
1.926
8.677(4)
9.786(5)
18.524(9)
75.037(6)
87.385(6)
67.783(6)
1404.3(11)
2
1.898
2.08
10.046(2)
11.615(3)
17.083(4)
94.972(3)
90.299(3)
114.862(3)
1799.9(7)
2
1.557
1.41
0.42 · 0.25 · 0.15
860
19.301(1)
20.636(1)
18.565(1)
90
117.954(1)
90
6531.6(1)
8
1.629
˚
b (A)
˚
c (A)
a (ꢁ)
b (ꢁ)
c (ꢁ)
˚
3
V (A )
Z
ꢀ
3
q (g cm
l (mm
Size (mm )
)
ꢀ1
)
3
2.31
1.47
0.55 · 0.50 · 0.38
1504
0.65 · 0.50 · 0.22
800
0.40 · 0.17 · 0.10
3248
F(000)
hmax (ꢁ)
27.6
26.5
26.5
27.5
Reflns collected
Unique reflns
Parameters
26033
3131
178
17794
5502
331
23586
7302
403
39294
14254
803
R
1
[I > 2r(I)]
2
(all data)
0.0952
0.2388
1.309
0.0484
0.1073
1.171
0.0216
0.0556
1.033
0.0322
0.0773
1.071
wR
GOF on F
2

N.C. Lloyd et al. / Journal of Organometallic Chemistry 691 (2006) 2757–2766
C(4)
2761
C(3)
C(3)
C(1)
O(12)
O(23)
Co(1)
O(13)
O(22)
O(32)
O(12)
O(32)
O(23)
P(3)
P(1)
P(2)
P(3)
C(12)
C(32)
P(2)
P(1)
C(32)
C(23)
O(22)
O(33)
O(11)
C(33)
O(21)
O(31)
O(11)
O(21)
O(31)
Cl(1)
C(46)
Sn(1)
Sn(1)
Cl(2)
C(61)
C(41)
C(62)
C(41)
C(42)
C(54) C(53)
Me
3
Fig. 1. The structure of Ph SnL (3). Bond parameters include: Sn(1)–
O(11) 2.213(2), Sn(1)–O(21) 2.248(2), Sn(1)–O(31) 2.229(2), Sn(1)–C(41)
˚
2
7
.172(3), Sn(1)–C(51) 2.177(3), Sn(1)–C(61), 2.174(3) A, O–Sn–O (av.)
9.4(1)ꢁ, C–Sn–C (av.) 103.3(1)ꢁ.
Me
2
Fig. 3. The structure of PhCl SnL (5). Bond parameters include: Sn(1)–
O(11) 2.044(4), Sn(1)–O(21) 2.111(3), Sn(1)–O(31) 2.071(3), Sn(1)–C(41)
˚
2
.111(5), Sn(1)–Cl(1) 2.385(20), Sn(1)–Cl(2) 2.385(2) A, O–Sn–O (av.)
C(5)
84.9(1)ꢁ, Cl(1)–Sn–C(41) 99.3(1)ꢁ, Cl(2)–Sn–C(41) 95.5(1)ꢁ, Cl(1)–Sn–
Cl(2) 97.40(5)ꢁ.
C(1)
O(33)
C(2)
O(13)
O(12)
C(332)
P(1)
C(2_7)
C(3_7)
O(21a)
P(3)
P(2)
C(331)
O(12)
Co(1)
P(2)
O(11)
O(21)
O(31)
C(41)
C(21)
O(11)
C(11)
O(21a_7)
P(1)
P(1_7)
Sn(1)
C(46)
O(12_7)
C(21_7)
O(11_7)
C(51)
C(12_7)
C(11_7)
Cl(1)
O(1)
O(1_7)
Sn(1)
C(52)
O(2)
Cl(2’)
Et
Cl(2’_7)
Fig. 2. The structure of Ph
2
ClSnL (12). Bond parameters include: Sn(1)–
Cl(1)
O(11) 2.156(1), Sn(1)–O(21) 2.182(2), Sn(1)–O(31) 2.159(1), Sn(1)–C(41)
.170(2), Sn(1)–C(51) 2.170(2), Sn(1)–Cl(1) 2.4523(7) A, O–Sn–O (av.)
2.3(1)ꢁ, C(41)–Sn–C(51) 104.3(1)ꢁ, C(41)–Sn–Cl(1) 98.14(5)ꢁ, C(51)–Sn–
˚
2
8
Me
3
SnL (6). Bond parameters include: Sn(1)–
Fig. 4. The structure of Cl
O(1) 2.084(9), Sn(1)–O(2) 2.064(12), Sn(1)–Cl(1) 2.367(5), Sn(1)–Cl(2)
.369(4) A, O–Sn–O (av.) 86.6(2)ꢁ, Cl–Sn–Cl (av.) 95.0(2)ꢁ.
Cl(1) 98.01(5)ꢁ.
˚
2
Me
Attempts to form Me SnL
by reaction of Me SnCl
3
3
Me
Me
with NaL
unexpectedly gave only Me ClSnL . This
(2) are well known, they are not usually significant under
2
has clearly arisen via a redistribution reaction:
such mild conditions (25 ꢁC, CH Cl ) so in this case must
2 2
R ꢀ
be promoted by [L ] . Because of the higher Lewis acidity
2
Me SnCl $ Me Sn þ Me SnCl
ð2Þ
Me
3
4
2
2
of Me SnCl , preferential reaction to give Me ClSnL
2
2
2
followed by reaction of the Me SnCl with the Kl a¨ ui li-
gand. Although redistribution reactions like that of Eq.
would shift the equilibrium of Eq. (2) to the right. There
2
2
1
19
was
Sn NMR evidence of corresponding redistribution

2762
N.C. Lloyd et al. / Journal of Organometallic Chemistry 691 (2006) 2757–2766
R
processes in the other syntheses, especially for Ph SnL ,
shorter than the corresponding distance in a number
3
˚
but these were slower and did not affect the yields.
of Cl Sn[(pz) BH] examples (typically 2.37–2.38 A)
3
3
Me
Similarly, a pure sample of MePhClSnL could not be
[5–7], suggesting similar bonding.
isolated because scrambling led to other combinations.
(ii) The Sn–O bonds also decrease across the series, with
those trans to C being consistently shorter than those
trans to Cl in the two examples where both are pres-
ent, which is the opposite of what would be expected
given the relative trans influences of C and Cl.
1
19
However the
Sn NMR (see below) could be deduced
from the mixture since the impurity peaks were well-
separated from the main component.
R
3
.2. X-ray crystal structures
(iii) The P@O bonds also decrease slightly as the L
ligand becomes more tightly bonded to Sn.
The structures of
a
full series of compounds,
(iv) The complexes tend more towards octahedral across
R
Ph3 Cl SnL were determined, to confirm the six-coordi-
the series, from C–Sn–C and O–Sn–O angles of
ꢀ n
n
Me
nation in each case and to monitor the changes in bond
103.3ꢁ and 79.4ꢁ, respectively, for Ph SnL to Cl–
3
parameters across the series.
Sn–Cl and O–Sn–O angles of 95.0ꢁ and 86.6ꢁ for
Me
Me
The crystal structure of Ph SnL
(3) revealed two
Cl SnL
3
.
3
structurally-equivalent independent molecules in the asym-
metric unit. The geometry of one is illustrated in Fig. 1 and
averaged bond parameters are given in the caption. The tin
atom is clearly six-coordinate, a very rare example for a tri-
organotin centre and the first with a SnC O coordination
These trends can all be explained by the increasing
Lewis acidity of the tin atom as less-bulky but more-
electronegative Cl atoms replace Ph groups.
3
3
sphere. The geometry about the tin atom is distorted octa-
3.3. NMR spectra
hedral, with average O–Sn–O angles of 79.4ꢁ and C–Sn–C
of 103.3ꢁ. This will be a consequence of the small bite of the
The complexes prepared in this study are particularly
interesting for NMR study. They have several active nuclei
( H, C, P and Sn), have symmetry that leads to vir-
tual coupling effects, and show temperature-affected flux-
ional behaviour. Full data for each compound are listed
in Section 2.
Me
L
ligand and the steric interactions between the three fac
1
13
31
119
˚
Ph groups. The Sn–C bonds are 2.174(3) A, compared with
.122 A in Ph SnCl [18], and the Sn–O bonds average
.239(2) A which indicates reasonably strong bonding –
˚
2
2
3
˚
˚
for comparison Sn–O distances around 2.40 and 2.30 A
are found respectively for five-coordinate R SnCl-
3
1
13
3.3.1. H and C spectra
(
O@PPh ) and R SnCl (O@PPh ) complexes (R = Me,
3
2
2
3
Ph) [19].
For all of the compounds, the cyclopentadienyl rings
1
13
The structures of the remaining members of the series
are illustrated in Figs. 2–4, and bond parameters are
included in the captions. Table 2 compares selected param-
give single H and C resonances at ca. d 5.1 and
89 ppm, respectively, only marginally shifted from those
of the free ligand with no discernible coupling to the other
nuclei present.
eters amongst the different compounds. These show the fol-
Me
Me
lowing trends from the Ph SnL
example 3 to the
For the OMe groups on the L compounds (and the
3
Me
Et
1
13
Cl SnL complex 6:
OEt groups on L ) the spectra gave H and C patterns
complicated by virtual coupling effects, as has been ana-
3
(
i) Both the Sn–C and Sn–Cl bond lengths decrease as
lysed for other complexes with the Kl a¨ ui ligands [20].
Me
the Ph groups are replaced by Cl, with the Sn–Cl
Ph SnL
(3) is an example with C3v symmetry. In the
3
Me
1
˚
bond length in Cl SnL
at 2.368 A being slightly
H spectrum the methyl protons gave a multiplet at
3
Table 2
Selected bond parameters for complexes
Me
SnL (3)
Et
Me
Me
3
Cl SnL (6)
Ph
3
Ph
2
ClSnL (12)
PhCl
2
SnL (5)
˚
Bond lengths (A)
Sn–C
Sn–Cl
Sn–O (trans to C)
Sn–O (trans to Cl)
P@O
2.174(3)
2.239(2)
1.512(2)
2.170(2)
2.452(1)
2.157(2)
2.181(1)
1.517(1)
2.111(5)
2.385(1)
2.044(4)
2.099(3)
1.498(4)
2.368(5)
2.074(12)
1.490(13)
Bond angles (ꢁ)
O–Sn–O
C–Sn–C
C–Sn–Cl
Cl–Sn–Cl
79.4(1)
103.3(1)
82.30(5)
104.3(1)
98.07(5)
84.9(1)
86.6(1)
95.0(2)
97.4(1)
97.4(1)

N.C. Lloyd et al. / Journal of Organometallic Chemistry 691 (2006) 2757–2766
2763
3
.51 ppm, with virtual coupling to the phosphorus nuclei
which can be analyzed as an A X spin system. This ‘‘vir-
1
8
3
3
tual quartet’’ is symmetrical, with J
= 3.6, 2.9, and
P–H
3
.6 Hz. The effect is more noticeable in the coordinated
species than in the free ligand where the couplings
3
are unsymmetrical J
= 3.5, 3.1 and 3.6 Hz. Similarly
P–H
1
3
in the C spectrum the methyl carbons gave a virtual
quartet at 52.4 ppm, of four lines of equal intensity,
JP–C = 3.1 Hz. This was from the six equivalent carbons,
2
coupling to the three equivalent phosphorus, in an A X
6
3
[
CpCo{P(OCH ) O} SnPh ] spin system. As in the proton
3 2 3 3
spectra, this is slightly shifted from 50.7 ppm in the free
ligand, the coupling constant is also slightly increased from
2
JP–C = 2.6 Hz.
Cl SnL (6) also has C3v symmetry, so the H and
3
Me
1
13
C
methyl signals appeared as the expected virtual quartet.
Me
Analysis was the same as for Ph SnL
and details are
3
1
Me
Fig. 5. H NMR spectrum of Ph
2
ClSnL
.
given in Section 2.
Me
In Ph ClSnL
(4) the idealized symmetry is lowered
2
from C3v to C . The spectra are mainly first-order so anal-
s
1
ysis is reasonably straightforward. The H NMR signals of
rus atoms, but the pattern has second-order characteristics
as the intensities of the lines are not as predicted in simple
terms.
the methyl groups now show three distinct peaks – a triplet
3
at 3.44 pm with J
= 5.3 Hz, a doublet at 3.52 ppm
P–H
3
with JP–H = 10.6 Hz, and a triplet at 3.85 ppm with
The same pattern essentially repeats for the other Ph
3
Me
JP–H = 5.4 Hz. (Fig. 5).
compound with C symmetry, PhCl SnL (5) where the
s 2
1
13
H and C spectra again gave three multiplets for the
b
OMe groups, but with more pronounced second-order
affects which led to distorted shapes.
a
C
C
O
O
P
Et
The phenyl–tin analogues formed with the L ligand
showed essentially the same type of behaviour for the OR
groups on the ligand, other than the obvious extra com-
plexity arising from the Et versus the Me group.
O
Cl
O
For the methyl–tin compounds the ligand signals are
Sn
c
moderated by more rapid fluxionality. Thus for
C
O
Me
O
Me ClSnL
2
(8) the OCH signals appear as a quartet
3
Ca
O
P
P
from three pseudo-equivalent phosphorus atoms, while
1
3
the C shows a broad unresolved single peak for the
O
O
OCH groups. The methyl groups on the tin atom show
3
1
3
Cb
a resolved quartet in the C but no phosphorus coupling
could be resolved for the H signal at 0.43 ppm, which is
Cc
1
shifted considerably upfield from that in Me SnCl at
2
2
1
.21 ppm.
(
14)
Me
For MeCl SnL (9) the lower symmetry is more appar-
2
ent, with two distorted multiplets (2:1 intensity ratio) for
1
13
The three methyl signals can be explained with the help
of 14. This shows a projection of the molecule, indicating
the three distinct methyl groups, marked as C , C , and
the H and three separate complex multiplets for the
C
Me
for the ligand OCH groups, as seen for the Ph ClSnL
3 2
compound. The C of the tin–methyl is still a second-order
quartet.
1
3
a
b
C . C and C , are on phosphorus trans to phenyl groups,
c
a
b
1
13
and these show two similar triplets, with virtual coupling to
two equivalent P nuclei in an A X spin system. The
For the H and C spectra of all of the compounds,
varying the temperature between 300 and 220 K had little
affect on the patterns observed, despite the evidence from
1
2
2
remaining, C , only shows a doublet, coupling to one P
c
1
19
nucleus, in an A X spin system.
the Sn spectra (discussed below) that the molecules are
fluxional at ambient temperature.
6
1
3
Similarly the methyl signals in the C NMR spectrum
Me
of Ph ClSnL
(4) show two multiplets, the one at
2
2
31
3.3.2. P NMR spectra
5
2.6 ppm ( J
= 4.6 and 4.4 Hz), twice the intensity
P–C
2
31
Me
of the other at 53.7 ppm ( J
= 4.5 and 4.2 Hz). The cou-
The P NMR signal for Ph SnL was a single broad
3
P–C
pling is caused by two equivalent and one unique phospho-
peak at 117 ppm.

2764
N.C. Lloyd et al. / Journal of Organometallic Chemistry 691 (2006) 2757–2766
This is only slightly shifted from the free ligand at
12 ppm. On cooling to 220 K, coupling could be resolved
119 ppm, shows coupling to A as a doublet JAB = 172 Hz,
1
and the C part of the signal, also at 119 ppm, also shows
coupling to A as a doublet JAC = 113 Hz, both of which
are distorted and close to overlapping. JBC coupling is
too small to show any resolvable features.
2
Me
from tin satellites, J
= 77 Hz. Similarly for Cl SnL
3
Sn–P
there was a single broad peak at room temperature, but
cooling to resolve any coupling was precluded by poor
solubility.
3
1
Me
The P NMR spectrum for Me ClSnL was a broad
2
Me
31
For Ph ClSnL (4) at 300 K the P NMR spectrum is
multiplet at 300 K, but on cooling to 220 K a similar com-
2
Me
difficult to interpret, because of the broad line-width of the
pattern. At 220 K, the line-width is reduced, allowing the
signal to be resolved (Fig. 6). Processing with resolution
enhancement (LB = ꢀ5 Hz, and GB = 0.3 Hz) facilitated
the interpretation of the observed multiplicity. It was
assessed as a heavily distorted second-order system, which
can be described as an ABC pattern, where B and C are
only slightly different in chemical environment.
The A part of the signal at 122 ppm shows coupling with
B, JAB = 172 Hz, which then shows coupling to C,
JAC = 113 Hz to give a heavily distorted doublet of
doublets.
plex pattern as was seen for Ph ClSnL could be distin-
2
guished and interpreted the same way. The spectrum
recorded here (Fig. 7) is more complex than that reported
previously for the same compound, where it was recorded
in CD Cl at 202 K and was analysed as an AB spin sys-
2
2
2
tem with d = 119, d = 117, J = 146 Hz [12].
A
B
AB
3
1
Me
The P spectrum for PhSnCl L was a very broad sin-
2
gle peak at 300 K. On cooling to 220 K, the signal resolved
into a complicated multiplet (Fig. 8) which could not be
fully analysed.
Me
31
Similarly for MeCl SnL
the P spectrum at 300 K
2
was a single broad peak, which at 220 K gave a similar pat-
Me
The part of the signal which is closer to the B and C
parts of the signal was increased in intensity as would be
expected in a second-order system. This hinders immediate
recognition of the multiplicity. The B part of the signal, at
tern to that of the PhCl SnL analogue.
2
119
3.3.3. Sn NMR spectra
1
19
The
Sn NMR shifts gave a perfectly linear relation-
ship to the number of Ph groups for both of the
R
Ph3 Cl SnL series (R = Me, Et). This linear relation-
ꢀ n
n
ship is unusual, as the four-coordinate Ph
does not give a simple correlation [21]. However the six-
coordinate tin pyrazolyl-borate series, R3 Cl Sn-
SnCl series
n
4
ꢀ n
ꢀ n
n
[
(pz) BH] also showed linear plots [7].
3
Although the chemical shifts were straightforward, the
actual patterns were complex.
1
19
Me
The Sn spectrum for Ph SnL at 300 K showed the
3
expected quartet at ꢀ408 ppm, with AX coupling to three
3
equivalent phosphorus nuclei. The coupling observed was
2
JSn–P = 82 Hz. At 220 K the quartet was more clearly
31
Me
ClSnL at 220 K.
Fig. 6. P spectrum of Ph
2
31
Me
ClSnL at 220 K.
31
Me
Fig. 7. P NMR spectrum of Me
2
2
Fig. 8. P NMR spectrum of PhCl SnL at 220 K

N.C. Lloyd et al. / Journal of Organometallic Chemistry 691 (2006) 2757–2766
2765
2
resolved, and the coupling was JSn–P = 79 Hz which
3
1
matches the coupling for the tin satellites in the P spec-
Et
trum. Ph SnL
also gave the predicted quartet, at
3
Me
ꢀ
413 ppm, slightly shifted from that of Ph SnL
408 ppm but with the same coupling constant
at
3
ꢀ
2
J
= 82 Hz.
Sn–P
Me
For Cl SnL
where the same pattern was expected
there was only a single broad peak at 300 K. However at
20 K the signal appeared as a poorly resolved quartet, d
3
2
ꢀ
2
661 ppm, J
= 16 Hz. Further analysis was hampered
Sn–P
by low solubility.
Me
119
For Ph ClSnL
the
Sn NMR spectrum at 300 K
2
is
a
first-order doublet (JSn–P = 94 Hz) of triplets
(
JSn–P = 62 Hz). This can be described as an AX Y system
2
where A is tin and X and Y are phosphorus. There was lit-
tle change between this and the spectrum run at 220 K.
Me
119
For Me ClSnL the Sn spectra at 300 K showed an
2
119
Me
apparent quartet which was resolved as the temperature
Fig. 10.
2
Sn NMR spectra of PhCl SnL , from 290 to 220 K.
was lowered into a doublet of triplets as seen for
Me
Table 3
Variation in parameters from the
Ph ClSnL . The temperature at which the pattern could
2
119
Sn NMR variable temperature
be first resolved was 260 K. Clearly the methyl example is
more fluxional than the Ph analogue, but otherwise analy-
Me
2
spectra of PhCl SnL
Temperature (K)
Distance (Hz)
sis is straightforward. The Sn–P coupling constants differ
Me
1
2
3
4
between the Ph and Me examples, with Me ClSnL hav-
2
Me
3
2
280
2
2
250
2
2
2
00
90
39.0
33.8
31.8
28.8
24.1
20.3
28.3
30.4
36.0
(nil)
8.2
52.4
56.1
58.2
59.9
61.5
63.4
67.6
68.3
70.8
(nil)
12.0
13.7
15.9
19.7
22.9
28.4
29.8
33.1
ing 105 and 75 Hz and Ph ClSnL having 94, and 62 Hz,
2
respectively.
1
19
Me
10.2
13.5
17.4
20.3
10.2
6.7
In contrast, the
Sn spectra for PhCl SnL
were
2
70
60
much more complex. At 300 K four equally sized peaks
were found (Fig. 9), centred at ꢀ568.5 ppm.
As the temperature was lowered, to 220 K, the spectra
varied before reaching what appeared to be three doublets,
with the intensities in the ratio 2:1:1 (Fig. 10).
The apparent splitting parameters are listed in Table 3,
as defined in Fig. 11.
40
30
20
nil
A full explanation of the spectral behavior was not
Et
found. Very similar patterns were repeated for PhCl SnL
2
Me
and MeCl SnL , which shows the variations are repro-
2
0
R
ducible for all of the R Cl SnL compounds.
2
Me
The complex PhMeClSnL (10) was prepared to per-
Me
haps aid the understanding of the PhSnCl L
and Me-
2
Me
SnCl L
spectra. It should be a chiral compound, with
2
119
Me
119
Me
Fig. 9.
Sn NMR spectrum of PhCl
2
SnL at 300 K.
Fig. 11. Interpretation of the Sn NMR spectrum of PhCl
2
SnL
.

2766
N.C. Lloyd et al. / Journal of Organometallic Chemistry 691 (2006) 2757–2766
1
19
three distinct phosphorus environments leading to a Sn
NMR spectrum which should be a doublet of doublets of
doublets, in an AXYZ spin system.
[2] J.A. Zubieta, J.J. Zuckerman, Prog. Inorg. Chem. 24 (1978) 251;
A.G. MacDiarmid, Organometallic Compounds of the Group IV
Elements, Marcel Dekker, New York, 1968;
L. Pellerito, L. Nagy, Coord. Chem. Rev. 224 (2002) 111;
R. Jambor, L. Dostal, A. Ruzicka, I. Cisarova, J. Brus, M. Holcapek,
J. Holecek, Organometallics 21 (2002) 3996.
1
19
At 300 K, the Sn spectra of this compound showed a
complex multiplet, centered at ꢀ417.2 ppm. However, on
cooling to 220 K the expected doublet of doublets of
doublets was resolved, as eight lines of equal intensity.
[3] Cambridge Crystallographic Data Base, 2006 release; S.W. Ng, Z.
Kristallogr. 214 (1999) 424;
2
2
2
Z.G.K. Das, K.M. Lo, C. Wei, T.C. Mak, Organometallics 6 (1987)
JSn–P (A)
,
JSn–P (B) and JSn–P (C) were 81.2, 57.6 and
1
0;
1
00.0 Hz, respectively.
P. Steenwinkel, J.T.B.H. Jastrzebski, B.J. Deelman, D.M. Grove, H.
Kooljman, N. Veldman, W.J.J. Smeets, A.L. Spek, G. Van Koten,
Organometallics 16 (1997) 5486;
4
. Conclusion
K.M. Lo, S.W. Ng, V.G.K. Das, J. Crystallogr. Spectrosc. Res. 23
(
1993) 933.
The Kl a¨ ui ligands are excellent for tri-coordination to
[
[
4] B.K. Nicholson, J. Organometal. Chem. 265 (1984) 153.
5] S.K. Lee, B.K. Nicholson, J. Organometal. Chem. 309 (1986) 257;
G.G. Lobbia, G. Valle, S. Calogero, P. Cecchi, C. Santini, F.
Marchetti, J. Chem. Soc., Dalton Trans. (1999) 2119.
6] S. Calogero, G. Valle, G.G. Lobbia, S. Calogero, C. Santini, P.
Cecchi, L. Stievano, J. Organometal. Chem. 526 (1996) 269.
7] G.G. Lobbia, G. Valle, S. Calogero, P. Cecchi, C. Santini, F.
Marchetti, J. Chem. Soc., Dalton Trans. (1996) 2475.
organotin(IV) centres, conferring six-coordination with
even the least Lewis-acidic tin atoms. Resulting compounds
are stable, crystalline substances that are essentially air-sta-
ble – certainly more so than the corresponding complexes
with the pyrazolylborate ligands. The symmetry of the
resulting complexes leads to complex NMR, further
affected by room temperature fluxionality.
[
[
[8] S. Trofimenko, Scorpionates: the Coordination Chemistry of Poly-
pyrazolborate Ligands, Imperial College Press, London, 1999;
S. Trofimenko, Polyhedron 23 (2004) 197.
Acknowledgements
[
9] W. Kl a¨ ui, Angew. Chem., Int. Ed. Engl. 29 (1990) 627.
10] E.M. Holt, W. Kl a¨ ui, J.J. Zuckerman, J. Organometal. Chem. 335
1987) 29;
[
We thank Dr. Jan Wikaira and Professor Ward Rob-
inson, University of Canterbury, for collection of X-ray
intensity data. Assistance with NMR spectra from Dr.
R. Thomson is gratefully acknowledged. We thank Pro-
fessor W. Kl a¨ ui and Professor G. Haegele for useful
discussions.
(
W. Kl a¨ ui, N. Mocigemba, A. Weber-Schuster, R. Bell, W. Frank, D.
Mootz, W. Poll, H. Wunderlich, Chem. Eur. J. 8 (2002) 2335.
11] A.C. Filippou, P. Portius, G. Kociok-K o¨ hn, V. Albrecht, J. Chem.
Soc., Dalton Trans. (2000) 1759.
[
[
[
[
12] W. Kl a¨ ui, M. Glaum, E. Hahn, T. Lugger, Eur. J. Inorg. Chem.
(
2000) 21.
13] N.C. Lloyd, B.K. Nicholson, A.L. Wilkins, R.A. Thomson, Chem.
NZ 66 (2002) 237.
14] H.G. Kuivila, R. Sommer, D.C. Green, J. Org. Chem. 33 (1968)
Appendix A. Supplementary material
1
119.
Crystallographic data for the structural analyses have
been deposited with the Cambridge Crystallographic
Data Centre, CCDC nos. 292221–292224. Copies of this
information may be obtained free of charge from the
Director, CCDC, 12 Union Rd., Cambridge CB2 1EZ,
UK, e-mail: deposit@ccdc.cam.ac.uk or http://www.ccdc.
cam.ac.uk.
Full Supplementary Tables of NMR data and copies of
variable temperature NMR spectra can be obtained from
the authors (b.nicholson@waikato.ac.nz). Supplementary
data associated with this article can be found, in the online
version, at doi:10.1016/j.jorganchem.2006.02.010.
[15] G.M. Sheldrick, SHELX-97, University of G o¨ ttingen, G o¨ ttingen,
Germany, 1997.
[16] L.J. Farrugia, WINGX, University of Glasgow, UK, 2005;
L.J. Farrugia, J. Appl. Cryst. 32 (1999) 837.
[17] T.R. Ward, S. Duclos, B. Therrien, K. Schenk, Organometallics 17
(
1998) 2490.
[18] S.W. Ng, Acta Cryst. C 51 (1995) 2292.
[19] C.H. Yoder, A.L. Rheingold, M.B. Allen, Private Communication,
Cambridge Crystallographic Data Base, (1996);
S.W. Ng, V.G.K. Das, Acta Cryst. C 48 (1992) 1839;
H.J. Eppley, J.L. Ealy, C.H. Yoder, J.N. Spencer, A.L. Rheingold, J.
Organometal. Chem. 431 (1992) 133;
V.D. de Castro, C.A.L. Filgueiras, G.M. de Lima, M.T.P. Gam-
bardella, N.L. Speziali, Main Group Metal Chem. 24 (2001) 761;
D. Cunningham, E.M. Landers, P. McArdle, N.N. Chonchubhair, J.
Organometal. Chem. 612 (2000) 53.
References
[20] W. Kl a¨ ui, Z. Naturforsch. B 34 (1979) 1403;
W. Kl a¨ ui, W. Peters, N. Liedtke, S. Trofimenko, A.L. Rheingold,
R.D. Sommer, Eur. J. Inorg. Chem. (2001) 693.
[21] I. Omae, J. Organometal. Chem. Library 21 (1989) 1.
[
1] A.G. Davies, Organotin Chemistry, VCH, Germany, 1997;
C.E. Holloway, M. Melnik, Main Group Metal Chem. 23 (2000) 1.