Reactions of 1,8-bis(diphenylphosphino)naphthalene with Os3 (CO)12: C-H and C-P bond cleavage reactions

Article abstract of DOI:10.1016/j.jorganchem.2004.03.046

Reactions of Os₃(CO)₁₂ with 1,8-bis(diphenylphosphino)naphthalene (dppn) are described. Crystallographically characterised complexes isolated from a reaction carried out in refluxing toluene are Os₃ (μ-H)₂ {μ-PPh₂(nap)PPh(C₆ H₄)}₂ (CO)₆ (1), Os₃ (μ-H){μ₃ -PPh₂(nap)PPh(C₆ H₄)}(CO)₈ (2) and Os₂ (μ-PPh₂){μ-PPh₂(nap)} (CO)₅ (3) (nap=1,8-C₁₀H₆), while at r.t. in the presence of ONMe₃, only Os₃(CO) ₁₁ {PPh₂(1-C₁₀H₇)} (4) was isolated. While 1 and 2 contain ligands formed by metallation of a Ph group of dppn, as found also in complexes obtained from dppn and Ru₃(CO)₁₂, ligands in 3 and 4 are formed by cleavage of a P-nap bond, not found in the Ru series.

Full text of DOI:10.1016/j.jorganchem.2004.03.046

Journal of Organometallic Chemistry 689 (2004) 2415–2420
www.elsevier.com/locate/jorganchem
Reactions of 1,8-bis(diphenylphosphino)naphthalene with Os3(CO)12:
C–H and C–P bond cleavage reactions
a,
a
b
c
Michael I. Bruce *, Paul A. Humphrey , Reinhard Schmutzler , Brian W. Skelton ,
c
Allan H. White
a
Department of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia
Institut fu€r Anorganische und Analytische Chemie, Technische Universit€at Braunschweig, 38106 Braunschweig, Germany
Department of Chemistry, University of Western Australia, Crawley, WA 6009, Australia
b
c
Received 2 February 2004; accepted 26 March 2004
Abstract
Reactions of Os3(CO)12 with 1,8-bis(diphenylphosphino)naphthalene (dppn) are described. Crystallographically characterised
complexes isolated from a reaction carried out in refluxing toluene are Os3(l-H)2{l-PPh2(nap)PPh(C6H4)}2(CO)6 (1), Os3(l-H){l3-
PPh2(nap)PPh(C6H4)}(CO)8 (2) and Os2(l-PPh2){l-PPh2(nap)}(CO)5 (3) (nap ¼ 1,8-C10H6), while at r.t. in the presence of ONMe3,
only Os3(CO)11{PPh2(1-C10H7)} (4) was isolated. While 1 and 2 contain ligands formed by metallation of a Ph group of dppn, as
found also in complexes obtained from dppn and Ru3(CO)12, ligands in 3 and 4 are formed by cleavage of a P-nap bond, not found
in the Ru series.
Ó 2004 Elsevier B.V. All rights reserved.
1. Introduction
metal carbonyl clusters. Following an associated ac-
count of the reactions between dppn and Ru3(CO)10(L)2
(L ¼ CO, L2 ¼ dppm) [8], this paper describes some
complexes formed in reactions of dppn with Os3(CO)12.
The phosphorus analogue of 1,8-bis(dimethyla-
mino)naphthalene (‘‘proton spongeÒ’’), 1,8-bis(diph-
enylphosphino)naphthalene (dppn), is a highly basic
bis(tertiary phosphine). Contacts between the phenyl
groups on the phosphorus atoms result in considerable
distortion of the free ligand, so it is not surprising that
its metal complex chemistry has attracted much atten-
tion since the first report of this unusual phosphine [1].
2. Results and discussion
The reaction between Os3(CO)12 and dppn was car-
ried out in refluxing toluene for 24 h. Several products
were separated and purified by preparative t.l.c. and
characterised initially by electrospray mass spectrometry
(ES-MS) and single-crystal X-ray diffraction studies.
Plots of the three of the complexes are given in Figs. 1–3
and selected bond parameters are listed in Table 1.
An orange band ðRf 0:36Þ afforded Os3(l-H)2
{l-PPh2(nap)PPh(C6H4)}2(CO)6, (1; nap ¼ 1,8-C10H6
(Fig. 1), which has a crystallographic two-fold axis
passing through Os(2) and the centre of the Os(1,10)
vector. It contains two cyclometallated dppn ligands
which bridge the Os(1,10)–Os(2) vectors. Atoms P(1) and
ꢀ
The two phosphorus atoms are 3.05 A apart, much
ꢀ
shorter than the sum of the van der Waals radii (3.80 A.
Consequently, rigid chelate complexes are formed with
most metal centres. Examples containing molybdenum
[2], palladium [1–3], platinum [1,2] and gold [4–6] have
been described. Platinum(II) complexes containing 1,8-
(PRR0)2-naphthalenes (RR0 ¼ Me2, Me(C6F5), Cy2,
ButPh) have also been made [7]. Our interest in the co-
ordination and subsequent bond-cleavage reactions of
bidentate phosphines on metal clusters instigated a
survey of the reactions of dppn with trinuclear Group 8
ꢀ
P(2) chelate Os(1) [Os(1)–P(1,2) 2.378(6), 2.316(8) A],
while Os(2) is attached to C(112,1120) of the metallated
ꢀ
C6H4 rings [Os(2)–C(112) 2.19(2) A]. Each metal atom
* Corresponding author. Fax: +61-8-8303-4358.
E-mail address: michael.bruce@adelaide.edu.au (M.I. Bruce).
0022-328X/$ - see front matter Ó 2004 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2004.03.046

2416
M.I. Bruce et al. / Journal of Organometallic Chemistry 689 (2004) 2415–2420
104
CO(21)
Os(2)
103
102
105
106
104a
101
P(1)
107
121
108
211
111
122
112
111
P(1)
212
121
Os(1)
P(2)
221
CO(12)
CO(11)
CO(13)
CO(21)
122
Os(1)
222
CO(22)
102
Os(2)
P(2)
CO(11)
103
101
Fig. 1. Molecular projection of Os3(l-H){l3PPh2(nap)PPh(C6H4)}2-
(CO)6 (1), normal to the Os3 plane. Core hydrogen atoms not refined.
222
108a
CO(12)
104
108
212
104a
105
221
211
107
CO(22)
CO(23)
106
Os(2)
CO(21)
CO(12)
Fig. 3. Molecular projection of Os2(l-PPh2){l-PPh2(nap)}(CO)5 (3).
121
111
112
P(1)
CO(33)
Table 1
Os(1)
122
Os(3)
ꢀ
102
Selected bond distances (A) and angles (°)
CO(11)
P(2)
Compound
1
2
3
101
221
103
Os(1)–Os(2)
Os(1)–Os(3)
Os(2)–Os(3)
Os(1)–P(1)
3.040(2)
2.8567(4)
2.8413(4)
CO(32)
CO(31)
104
3.004(2) Os(10) 3.0251(4)
2.7568(4)
108a
222
108
2.378(6)
2.316(8)
2.332(1)
2.329(1)
2.394(2)
104a
105
211
Os(1)–P(2)
212
Os(1)–C(101)
Os(1)–C(102)
Os(2)–C(101)
Os(2)–C(111)
Os(2)–C(112)
Os(3)–C(112)
Os(1)–H
2.369(7)
2.362(8)
2.120(9)
107
106
2.419(5)
2.341(5)
2.152(5)
1.82(7)
2.19(2)
Fig. 2. Molecular projection of Os3(lH){l3PPh2(nap)PPh(C6H4)}-
(CO)8 (2), normal to the Os3 plane.
Os(3)–H
1.76(7)
P(1)–C(101)
P(1)–C(111)
P(1)–C(121)
P(2)–C(108)
P(2)–C(211)
P(2)–C(221)
C(111)–C(112)
1.87(3)
1.85(3)
1.87(2)
1.83(3)
1.82(3)
1.85(3)
1.39(4)
1.845(5)
1.817(6)
1.835(6)
1.829(5)
1.835(5)
1.827(5)
1.443(8)
1.819(8)
1.834(8)
1.810(10)
1.836(8)
1.821(11)
carries two terminal CO groups. Two cluster-bonded
1
hydrogens were detected in the H NMR spectrum (d
)12.39) as a double doublet of doublets, arising from
coupling to phosphorus in the ligand, but these could
not be located in the X-ray study. However, the long
0
ꢀ
Os–Os separations [Os(1,1 )–Os(2) 3.004, 3.040(2) A] are
consistent with the presence of l-H atoms. The cluster
valence electron (c.v.e.) count is 48.
ꢀ
C(111, 112) 2.419, 2.341(5) A], while the H atom, lo-
cated and refined, bridges the Os(1)–Os(3) vector. Eight
CO groups [three each on Os(2,3), two on Os(1)] com-
plete the coordination, the cluster as a whole having 48
cluster valence electrons (c.v.e.), as expected for an M3
cluster with three M–M bonds. In the ruthenium ana-
logue [8], corresponding distances involving the metal
atoms are 0.03–0.05 A shorter, further confirming the
similar atomic radii for these two elements in cluster
carbonyl complexes of this type [9].
Complex 2 was isolated from an orange band
ðRf 0:44Þ and shown to be Os3(l-H){l3-PPh2(nap)PPh-
(C6H4)}(CO)8 (Fig. 2). The complex is isomorphous and
isostructural with the ruthenium derivative described
earlier [8]. The bis(phosphine) ligand chelates one Os
ꢀ
atom [Os(1)–P(1,2) 2.332, 2.329(1) A] while an ortho
C–H bond of one of the phenyl groups has added to
ꢀ
ꢀ
Os(3) [Os(3)–C(112) 2.152(5) A]. This brings this C6H4
group within g2-bonding distance of Os(2) [Os(2)–

M.I. Bruce et al. / Journal of Organometallic Chemistry 689 (2004) 2415–2420
2417
The fastest running complex ðRf 0:53Þ was pale yel-
low binuclear Os2(l-PPh2){l-PPh2(nap)}(CO)5 (3). As
shown in Fig. 3, an Os(CO)3 group is linked to an
(nap)PPh, and PPh2P(nap) ligands; in two examples,
cluster-bound C6H4 ligands, derived from one of the P–
Ph groups, were also present [8]. In all cases, and also
that of Ru3(l-dppm)(CO)8(dppn), the P(nap)P fragment
chelates one ruthenium atom, but no example of cleav-
age of the P-nap bond was found. The osmium com-
plexes described above contain PPh2(nap)PPh(C6H4),
PPh2(nap) and PPh2 ligands, thus showing an increased
tendency for cleavage of the nap-P bond. In 1, two li-
gands derived from dppn are attached to the Os3 cluster.
During one reaction, transfer of an H atom to the
PPh2(nap) fragment allows formation of the tertiary
phosphine PPh2(1-C10H7).
ꢀ
Os(CO)2 fragment by an Os–Os bond [2.8413(4) A]
which is bridged by a PPh2 group [Os(1,2)–P(1) 2.394,
ꢀ
2.326(2) A] and the PPh2(nap) fragment. The latter is
attached to Os(1) by an g2 interaction with C(101)–
C(102) of the naphthyl group [Os(1)–C(101,102) 2.369,
ꢀ
2.362(8) A] and to Os(2) by atom P(2) and a r-bond to
ꢀ
C(101) [Os(2)–P(2) 2.348(2); Os(2)–C(101) 2.120(9) A].
To our knowledge, this is the first example of a l-
g1,P : g2-PR2(nap) fragment which has been structur-
ally characterised.
The reaction between Os3(CO)12 and dppn was also
run at r.t. in thf in the presence of ONMe3 (tmno). After
1 h, spot t.l.c. showed that many products had formed,
but only one of these has been identified crystallo-
graphically, as yellow Os3(CO)11{PPh2(1-C10H7)} (4).
This complex is a conventional mono-substitution
product of Os3(CO)12 in which the ligand is derived
from dppn by replacement of a PPh2 group by H, i.e.,
diphenyl(1-naphthyl)phosphine. As can be seen from
Fig. 4, the molecular structure is similar to that of many
other Os3(CO)11(PR3) complexes, with Os–Os bond
3. Conclusions
The close proximity of the two phosphorus donor at-
oms in dppn results in characteristic chelating behaviour
towards transition metals, further exemplified in its re-
actions with trinuclear metal carbonyl clusters M3(CO)12
(M ¼ Ru [8], Os). The present work has shown that C–H
bond cleavage occurs with one of the Ph groups to give
the ligand PPh2(nap)PPh(C6H4), found in two com-
plexes. In 1, two of the metallated ligands bridge two of
the three Os–Os vectors, there being no further bonding
of the cluster to the C6H4 groups. In 2, coordination of
this ligand to all three Os atoms occurs by chelation of
one Os by the two P atoms, and metallation of one Ph
group by a second Os atom, while the third Os atom has
an g2 interaction with this C6H4 group. In 3, fragmen-
tation of the Os3 cluster has occurred, to give an Os2
complex in which the Os–Os bond is bridged by PPh2 and
PPh2(nap) ligands. Under mild conditions, the cluster
aids degradation of the dppn to PPh2(1-C10H7), which is
found in 4. Thus in contrast to the Ru3 system, cleavage
of the P-nap bond has occurred in two of these products.
ꢀ
lengths between 2.8862 and 2.9070(3) A [the longest is
Os(1)–Os(2), which shows the usual cis lengthening
found in this type of complex]. The tertiary phosphine
ligand occupies an equatorial site on Os(1) [Os(1)–P
ꢀ
2.378(1) A], with P–C(aryl) bond lengths ranging be-
ꢀ
tween 1.829(4) and 1.842(6) A.
In the reactions of dppn with Ru3(CO)12, ready
cleavage of aryl C–H and Ph–P bonds occurred to give
complexes containing PPh2(nap)PPh(C6H4), PPh2-
CO(34)
CO(33)
CO(32)
CO(31)
CO(13)
CO(24)
4. Experimental
CO(11)
CO(22)
Os(1)
Os(2)
4.1. General experimental conditions
CO(12)
106
CO(21)
107
108
All reactions were carried out under dry, high purity
nitrogen using standard Schlenk techniques. Common
solvents were dried, distilled under argon and degassed
before use.
104a
P(1)
101
CO(23)
105
108a
103
122
104
102
111
112
121
4.2. Instrumentation
Infrared spectra were obtained on a Bruker IFS28 FT-
IR spectrometer. Spectra in CH2Cl2 were obtained using
a 0.5 mm path-length solution cell with NaCl windows.
1H NMR spectra were recorded on Bruker AM300WB
or ACP300 instruments at 300.13 MHz. Samples were
dissolved in CDCl3 or CD2Cl2 contained in 5 mm sample
Fig. 4. Molecular projection of Os3(CO)11{PPh2(1-C10H7)} (4), nor-
mal to the Os3 plane. Selected bond parameters: Os(1)–Os(2)
2.9070(3), Os(1)–Os(3) 2.8878(2), Os(2)–Os(3) 2.8862(3), Os(1)–P(1)
2.378(1), P(1)–C(101) 1.836(4), P(1)–C(111) 1.842(6), P(1)–C(121)
ꢀ
1.829(4) A; Os(2)–Os(1)–P(1) 103.23(3)°; Os(3)–Os(1)–P(1) 162.64(3)°.

2418
M.I. Bruce et al. / Journal of Organometallic Chemistry 689 (2004) 2415–2420
tubes. Chemical shifts are given in ppm relative to in-
1
39.07; H, 2.03%; M, 1292. IR (CH2Cl2): m(CO) 2062m,
2024vs, 1999m, 1974m (br), 1956w, 1935 (sh), 1919 (sh)
cmꢀ1. 1H NMR (CDCl3): d )17.32 [dd, 1H, J(HP) 14.4,
12.9, OsH], 6.31–8.05 (m, 25H, Ph + C6H4 + nap). ES-
MS (positive ion, MeOH, m=z): 1292, Mþ; (negative ion,
MeOH + NaOMe, m=z): 1323, [M + OMe]ꢀ, 1291, [M–
H]ꢀ. Band 3 (yellow, Rf 0:53) contained several com-
pounds, fractional crystallisation giving pale yellow
crystals (from CH2Cl2/MeOH) of Os2(l-PPh2){l-
PPh2(nap)}(CO)5 (3). Anal. Calc. (C39H26O5Os2P2): M,
1018. IR (CH2Cl2): m(CO) 2076s, 2039vs, 2035 (sh),
ternal tetramethylsilane for H. ES-MS were measured
with a VG Platform 2, solutions in MeOH, containing
NaOMe as an aid to ionisation [10], being directly in-
fused into the instrument. Elemental analyses were per-
formed by CMAS, Melbourne, Australia.
4.3. Reagent
The ligand dppn [11] was prepared by the cited
method.
1991vs, 1981 (sh), 1972 (sh), 1924w cmꢀ1 1H NMR
.
4.4. Reaction of Os3(CO)12 with dppn in refluxing toluene
(CDCl3): d 6.16–8.22 (m, 26H, Ph + nap). ES-MS (po-
sitive ion, MeOH, m=z): 2057, [2M + Na]þ; 1041,
[M + Na]þ; 1018, Mþ. The small amount of compound
finally obtained precluded getting accurate microana-
lytical data. Band 4 (yellow, Rf 0.83) contained
Os3(CO)12 (31.7 mg, 28%), identified by IR. Other bands
contained trace amounts of unidentified compounds.
A mixture of Os3(CO)12 (113 mg, 0.125 mmol) and
dppn (62 mg, 0.12 mmol) was heated in refluxing toluene
(20 ml) for 24 h. After evaporation to dryness, pre-
parative t.l.c. (acetone/hexane 1/3) separated several
products. Band 1 (orange, Rf 0.36) contained Os3(l-
H)2{l-PPh2(nap)PPh(C6H4)}2(CO)6 (1) (10.2 mg, 5%),
obtained as orange crystals from CH2Cl2/hexane. Anal.
Found: C, 51.61; H, 2.87. Calc. (C74H52O6Os3P4): C,
51.33; H, 3.03%; M, 1732. IR (CH2Cl2): m(CO) 2015m,
1992vs, 1979m, 1955 (sh), 1944 (sh), 1939w, 1918m
4.5. Reaction of Os3(CO)12 with dppn at r.t.
Solid Me3NO (9 mg, 0.1 mmol) was added to a so-
lution of Os3(CO)12 (46 mg, 0.051 mmol) and dppn (25
mg, 0.050 mmol) in thf (15 ml) and the mixture was
stirred for 2.5 h at r.t. Preparative t.l.c. (acetone/hexane
1/2) separated several bands. Bands 1 (yellow, Rf 0.38;
2.3 mg) and 2 (orange, Rf 0.43; 7.8 mg) are presently
unidentified; the latter has m(CO) at 2108vw, 2090w,
2073vs, 2049w, 2033 vs, 2004 (sh), 1990vs (br), 1972m,
1956m, 1927w cmꢀ1 (CH2Cl2), ES-MS (negative ion,
MeOH + NaOMe, m=z) 1309. Band 3 (green, Rf 0:66;
1
cmꢀ1. H NMR (CD2Cl2): d )12.39 [2 ꢁ dd, 2H, J(HP)
19.2, 12.6 and 21.0, 12.4, 2 ꢁ OsH], 5.87–8.11 (m, 50H,
Ph + C6H4 + nap). ES-MS (positive ion, MeOH, m=z):
1732, Mþ; (with added NaOMe in MeOH, m=z): 1755,
[M + Na]þ. Band 2 (orange, Rf 0.44) contained Os3(l-
H){l3-PPh2(nap)PPh(C6H4)}(CO)8 ꢂ CH2Cl2 (2) (30 mg,
19%) obtained as crystals from CH2Cl2/hexane. Anal.
Found: C, 39.11; H, 2.07%. Calc. (C42H26O8Os3P2): C,
Table 2
Crystal data and refinement details
Compound
1
2
3
4
Formula
MW
C74H52O6Os3P4 ꢂ 1.36CH2Cl2 C42H26O8Os3P2 ꢂ CH2Cl2
C39H26O5Os2P2
1017.0
C33H17O11Os3P ꢂ 0.5CH2Cl2
1847.7
Monoclinic
C2=c
1376.1
Triclinic
1233.5
Triclinic
Crystal system
Space group
Monoclinic
P21
9.9014(6)
17.402(1)
10.7700(7)
ꢁ
ꢁ
P1
P1
ꢀ
a (A)
16.723(9)
20.114(10)
20.622(10)
10.390(2)
14.040(2)
15.160(2)
85.801(4)
85.691(4)
84.730(4)
2191
12.2716(8)
12.3073(8)
12.3651(8)
87.306(2)
79.418(2)
64.345(2)
1654
ꢀ
b (A)
ꢀ
c (A)
a (°)
b (°)
c (°)
102.61(2)
109.371(1)
3
ꢀ
V (A )
6769
1751
Z
4
1.811
2
2.086
2
1.929
2
2.477
Dc (g cmꢀ3
)
l (cmꢀ1
Crystal size (mm)
)
5.9
0.27 ꢁ 0.17 ꢁ 0.07
8.9
7.4
0.11 ꢁ 0.07 ꢁ 0.06
11.7
0.20 ꢁ 0.17 ꢁ 0.11
0.59
64
0.18 ꢁ 0.15 ꢁ 0.13
0.54
75
Tmin = max
2hmax (°)
Ntot
0.66
50
0.72
75
8491
4953(0.11)
1882
40 850
45 891
8955(0.028)
8144
34 480
NðRint
Þ
15 469(0.042)
9717
0.031
17 029(0.041)
12 932
0.037
No
R
Rw
0.052
0.067
0.033
0.041
0.042
0.039

M.I. Bruce et al. / Journal of Organometallic Chemistry 689 (2004) 2415–2420
2419
3.2 mg) was crystallised (CH2Cl2/MeOH) to give yellow
crystals of Os3(CO)11{PPh2(nap)}(4). IR (CH2Cl2):
m(CO) 2108w, 2055vs, 2032m, 2018vs, 1989w, 1978w,
112
111
(CO)2
Os2
1
1952w cmꢀ1. H NMR (CDCl3): d 7.05–7.97 (m, 17H,
Ph
Ph
H
H
P1'
P1
Ph + C10H7). ES-MS (negative ion, MeOH + NaOMe,
m=z): 1223, [M + OMe]ꢀ. Band 4 ðRf 0:91Þ contained
Os3(CO)12 (1.2 mg, 3%).
101
108
(OC)2Os1
P2Ph2
Os1' (CO)2
P
Ph2
4.6. Structure determinations
(1)
Full spheres of diffraction data were measured at ca.
153 K using a Bruker AXS CCD area-detector instru-
ment. NtotðalÞ reflections were merged to N unique ðRint
cited) after ‘‘empirical’’/multiscan absorption correction
(proprietary software), No with F > 4rðF Þ being used in
the full matrix least squares refinements. All data were
measured using monochromatic Mo Ka radiation,
108
111
112
Ph
P1
101
101
P2Ph2
Os2(CO)2
Os2
(CO)3
108
(OC)3Os1
Os1
Os3(CO)3
P2
(CO)2
P1
H
Ph2
Ph2
ꢀ
k ¼ 0:71073 A. Anisotropic displacement parameter
(3)
(2)
forms were refined for the non-hydrogen atoms, (x, y, z,
Uiso H being constrained at estimated values. Conven-
)
(CO)4
Os3
tional residuals R, Rw on jF j are quoted [weights:
(r2ðF Þ þ 0:000nwF 2Þꢀ1ꢃ. Neutral atom complex scatter-
ing factors were used; computation used the XTAL 3.7
program system [12]. Pertinent results are given in the
Figures (which show non-hydrogen atoms with 50%
probability amplitude displacement ellipsoids and
(OC)3Os1
P1Ph2
Os2(CO)4
ꢀ
101
hydrogen atoms with arbitrary radii of 0.1 A) and
Table 2.
(4)
4.7. Variata
1. Fracture of the most auspicious available specimen
during data acquisition resulted in only a hemisphere of
useful data, already limited in scope as a consequence of
partial desolvation (solvent occupancy refining to 0.68)
and supportive of anisotropic displacement parameter
refinement for Os, P, Cl only. Core hydrogen atoms,
postulated from the NMR, were not located.
2. Core hydride atoms were located and refined in (x,
y, z, Uiso). Difference map residues were modelled as
equal disordered components of CH2Cl2 (site occupan-
cies: 0.5), with constrained geometries.
Acknowledgements
We thank the Australian Research Council for sup-
port of this work, Dipl. Chem. S. Okucu (Braunschweig)
for a gift of dppn used in this work, Professor B.K.
Nicholson (University of Waikato, Hamilton, New
Zealand) for the mass spectra, and Johnson Matthey
plc, Reading, UK, for a generous loan of OsO4.
3. Friedel data were preserved distinct, xobs refining to
0.007(9).
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