Direct access to cis-1,2-dihydro-1,2-diphosphetes from butadiynes and terminal phosphinidene complexes

Article abstract of DOI:10.1021/om970487t

Transient terminal phosphinidene complexes [RP→W(CO)₅] (R = Ph, Me, Bz, allyl), as generated from the corresponding 7-phosphanorbornadiene complexes, react with substituted butadiynes to afford the corresponding 3-alkynyl-1,2-dihydro-1,2-diphosphete complexes by insertion of a second phosphinidene unit into the alkynyl-substituted P-C ring bond of the initially formed phosphirene complexes. According to the X-ray analysis of one of the products, the stereochemistry of the substituents on the P-P bond is cis.

Full text of DOI:10.1021/om970487t

Organometallics 1997, 16, 4501-4504
4501
Dir ect Access to cis-1,2-Dih yd r o-1,2-d ip h osp h etes fr om
Bu ta d iyn es a n d Ter m in a l P h osp h in id en e Com p lexes
Ngoc Hoa Tran Huy, Louis Ricard, and Fran c¸ ois Mathey*
Laboratoire “H e´ t e´ ro e´ l e´ ments et Coordination”, URA 1499 CNRS, DCPH, Ecole Polytechnique,
9
1128 Palaiseau Cedex, France
Received J une 10, 1997X
Summary: Transient terminal phosphinidene complexes
RPfW(CO)5] (R ) Ph, Me, Bz, allyl), as generated from
Resu lts a n d Discu ssion
[
The phosphinidene complex [PhPfW(CO)5] was gen-
erated from the corresponding 7-phenyl-7-phosphanor-
bornadiene complex 1 in the presence of CuCl as a
the corresponding 7-phosphanorbornadiene complexes,
react with substituted butadiynes to afford the corre-
sponding 3-alkynyl-1,2-dihydro-1,2-diphosphete com-
plexes by insertion of a second phosphinidene unit into
the alkynyl-substituted P-C ring bond of the initially
formed phosphirene complexes. According to the X-ray
analysis of one of the products, the stereochemistry of
the substituents on the P-P bond is cis.
7
catalyst at around 60 °C. Its reaction with 1,6-
diphenoxy-2,4-hexadiyne afforded the 1,2-dihydro-1,2-
diphosphete complex 2 as a pure isomer in 47% yield.
In tr od u ction
The chemistry of 1,2-dihydro-1,2-diphosphetes dis-
1
plays such versatility that a number of groups have
investigated their synthesis. The first described route
involves the condensation of cyclopolyphosphines with
2
alkynes. Despite its simplicity, this approach gives
The NMR data of 2 are very characteristic. The 31P
NMR spectrum shows the presence of two nonequivalent
phosphorus atoms: AB system, δ 43.38 and 49.37,
only modest yields of thermally robust 1,2-dihydro-1,2-
diphosphetes, together with several other larger rings.
More recently, the related [2 + 2] cycloaddition of
diphosphene complexes with alkynes has afforded a
series of diphosphete complexes under much milder
conditions and with better selectivity.3 Alternatively,
1
3
∑J (P-P) ) 28.1 Hz. One of the C resonances of the
ring carbons appears at 156.6 ppm as a multiplet with
1
2
J (C-P) )30.5 Hz, J (C-P) )16.8 Hz. The course of
the reaction leading to 2 was monitored by 31P NMR;
this showed the initial formation of a phosphirene
complex (δ -123.4) by [1 + 2] cycloaddition of the
phosphinidene to the alkyne, followed by the insertion
of a second phosphinidene unit into one of the intracyclic
P-C bonds. The insertion reaction appears to be highly
favored with respect to the [1 + 2] cycloaddition on the
second alkyne unit; indeed, no trace of bis-phosphirene
complex has been detected.
1
,2-dihydro-1,2-diphosphetes can be obtained via the
formal insertion of a phosphenium ion into a three-
membered phosphirene ring, the reaction of sterically
stabilized iminophosphines with phosphirenes, or the
Zr-to-P metathetical exchange on 1-phospha-2-zircona-
cyclobutenes. Many other approaches of more limited
generality also exist.1 While investigating the reaction
of electrophilic terminal phosphinidene complexes with
substituted butadiynes, we observed an unexpected
insertion of the phosphinidene complexes into the
4
5
6
The analogous reaction of [PhPfW(CO)5] (1) with 2
equiv of 1,4-diphenyl-1,3-butadiyne led to the phos-
phirene complex 3, with only 6% of the corresponding
7
initially formed phosphirene ring, leading to a series
of new 1,2-dihydro-1,2-diphosphete complexes instead
of the expected 2,2′-bis(phosphirenyl) species. This
observation is the subject of this report.
1
,2-diphosphete 4. The reaction was complete in 5 h,
31
and 3 was isolated in 55% yield. The P NMR signal
X
Abstract published in Advance ACS Abstracts, September 15, 1997.
(1) (a) Mathey, F.; Charrier, C.; Maigrot, N.; Marinetti, A.; Ricard,
L.; Tran Huy, N. H. Comments Inorg. Chem. 1992, 13, 61. (b) Kummer,
S.; Zenneck, U. In Comprehensive Heterocyclic Chemistry II; Katritzky,
A. R., Rees, C. W., Scriven, E. F. V., Eds.; Pergamon: Oxford, 1996;
Vol. 1b, p 1157.
(2) (a) Mahler, W. J . Am. Chem. Soc. 1964, 86, 2306. (b) Ecker, A.;
Schmidt, U. Chem. Ber. 1973, 106, 1453. (c) Charrier, C.; Guilhem, J .;
Mathey, F. J . Org. Chem. 1981, 46, 3. (d) Charrier, C.; Maigrot, N.;
Mathey, F.; Robert, F.; J eannin, Y. Organometallics 1986, 5, 623. (e)
Philips, I. G.; Ball, R. G.; Cavell, R. G. Inorg. Chem. 1988, 27, 2269.
(
3) Tran Huy, N. H.; Inubushi, Y.; Ricard, L.; Mathey, F. Organo-
metallics 1997, 16, 2506.
4) Ricard, L.; Maigrot, N.; Charrier, C.; Mathey, F. Angew.Chem.,
Int. Ed. Engl. 1987, 26, 548.
(
of 3 appears at -133.9 ppm; the proposed structure was
established by X-ray analysis (see later). The isolation
of the phosphirene complex 3 allowed us to confirm
unambiguously the feasibility of the insertion of phos-
(5) Linck, M.; Niecke, E.; Nieger, M. Chem. Ber. 1994, 127, 313.
(6) Breen, T. L.; Stephan, D. W. Organometallics 1997, 16, 365.
(7) Marinetti, A.; Mathey, F.; Fischer, J .; Mitscher, A. J . Am. Chem.
Soc. 1982, 104, 4484.
S0276-7333(97)00487-1 CCC: $14.00 © 1997 American Chemical Society

4
502 Organometallics, Vol. 16, No. 20, 1997
Notes
phinidene complexes into the P-C ring bond, leading
to the corresponding diphosphete derivatives. Thus, the
phosphirene complex 3 was allowed to react with an
additional amount of 7-phosphanorbornadiene complex
1
. At 60 °C, in the presence of a catalytic amount of
CuCl, the insertion of [PhPW(CO)5] into the phosphirene
takes place, leading to the expected four-membered
3
ring 4, which was isolated in 60% yield. Only one
isomer of 4 has been obtained, as in the case of 2. The
insertion reaction into 3 has been extended to other
phosphinidene complexes. [MePW(CO)5], as generated
7
from the 7-methyl-7-phosphanorbornadiene complex 5,
reacts with 3 to afford the diphosphete complex 6, which
was isolated as a single isomer and fully characterized.
This reaction is both regio- and stereoselective; the
insertion was supposed to take place into the P-C ring
bond bearing the acetylenic substituent, but an unam-
biguous structural assignment could not be inferred
from the NMR data.
F igu r e 1. ORTEP drawing of one molecule of 8, as
determined by a single-crystal X-ray diffraction study.
Ellipsoids are scaled to enclose 50% of the electron density.
Hydrogen atoms are omitted for clarity. Selected bond
lengths (Å) and angles (deg) : W
.482(2), P -C 1.825(7), P -P 2.283(3), P
-C 1.35(1), C -C16 1.46(1), C -P 1.831(7), C
-C 1.852(6); W -P -C
-P -C 116.4(2), C -P
106.0(3), P -P -C 103.1(2), P
-P 104.8(5), W -P -P
1
-P
1
2.510(2), W
-C 1.818(7),
-C22 1.44-
118.5(2),
2
-P
2
2
C
1
1
1
2
1
3
1
2
1
2
2
2
(
W
1), C22-C23 1.19(1), P
2
9
1
1
1
1
-P
1
-P
-P
2
129.27(8), W
-C
-C
1
1
3
1
1
-P
1
2
75.5-
(2), C
1
1
3
2
1
3
-C
2
1
-C
2
Under the same conditions, the 7-benzyl-7-phospha-
norbornadiene 7 and 7-allyl-7-phosphanorbornadiene
1
04.5(5), C
1
2
2
2
2
1
122.0(7), W
-P
2
-
8
C2 114.2(2), W -P -C 119.2(2), P -P -C 75.0(2), P -
2
2
9
1
2
2
1
9
9
react with the phosphirene 3 to afford the corre-
P
2
-C
9
109.2(3), C
2
-P
2
9
-C 108.6(3).
sponding 1,2-diphosphetes 8 and 10 in 60% yields.
These reactions are also totally regio- and stereoselec-
tive. In order to establish into which P-C phosphirene
bond the insertion of phosphinidene takes place, we
performed the X-ray crystal structure analysis of 8
(Figure 1). As expected, the insertion of the ben-
zylphosphinidene unit has taken place into the
P-C(CtCPh) ring bond. But quite unexpectedly, the
insertion has produced exclusively the least stable
stereoisomer with the two carbon and tungsten P-P
substituents in the cis disposition.10 It must be empha-
sized that [PhPW(CO)5] does not insert into the P-C
bonds of other, C-alkyl- or -aryl-substituted phosphirene
complexes under similar conditions. The presence of the
acetylenic substituent appears to be crucial for the
insertion to take place. The X-ray crystal structure
analysis of the phosphirene complex 3 (Figure 2) gives
some clue for the increased reactivity of 3 with respect
to other phosphirene complexes. Indeed, the P-C2 is
somewhat longer than the P-C1 bond: 1.806(3) vs
1
.789(3) Å . It must be stressed that the intracyclic P-C
bond lengths of [(triphenylphosphirene)W(CO)5] are
strictly identical (1.790(4) and 1.787(4) Å) to the length
F igu r e 2. ORTEP drawing of one molecule of 3, as
determined by a single-crystal X-ray diffraction study.
Ellipsoids are scaled to enclose 50% of the electron density.
Hydrogen atoms are omitted for clarity. Selected bond
lengths (Å) and angles (deg) : P-C 1.789(3), P-C 1.806-
7
of P-C1 in 3. In the same vein, the C2-C3 bond of 3 is
longer, at 1.320(4) Å, than the corresponding bond in
[(Ph2C2PPh)W(CO)5] (1.307(6) Å). Thus, it appears that
1
2
the alkynyl substituent weakens the adjacent CdC and
P-C bonds, probably through a conjugative destabiliz-
ing interaction. Any proposed insertion mechanism
must rationalize both the regio- and stereoselectivity of
(3), C
11 1.449(4), C
3.1(1), C -P-C
9.1(2), P-C -C
21.1(1), W-P-C
11143.2(3).
1
-C
2
1.320(4), P-C
-C 1.403(4), C
107.9(1), C -P-C
-P-W 123.5(1), C
-C -C 146.0(3), C
5
1.823(3), P-W 2.4870(8), C
-C 1.198(5); C -P-C
109.1(1), P-C -C
1
-
C
2
3
3
4
1
2
4
6
1
1
5
2
5
1
2
2
1
67.8(2), C
125.0(1), C
1
2
-P-W
-C -
5
1
2
3
2
1
C
(8) Tran Huy, N. H.; Mathey, F. Unpublished results.
(
9) Svara, J .; Marinetti, A.; Mathey, F. Organometallics 1986, 5,
1
161.
10) Maigrot, N.; Ricard, L.; Charrier, C.; Le Goff, P.; Mathey, F.
Bull. Soc. Chim. Fr. 1992, 129, 76.
the reaction. A direct insertion into the P-C ring bond
is ruled out because it would certainly afford the less
(

Notes
Organometallics, Vol. 16, No. 20, 1997 4503
+
+
+
Sch em e 1. P r op osed Mech a n ism for th e
F or m a tion of cis-1,2-Dih yd r o-1,2-d ip h osp h etes
intensity) 1126 (M , 18), 1042 (M - 3CO, 34), 902 (M - 8CO,
+
59), 846 (M - 10 CO, 100).
[
1,2-D ip h e n y l-3-p h e n e t h y n y lp h o s p h ir e n e ]p e n t a -
ca r bon yltu n gsten (3). A solution of 7-phosphanorborna-
-
3
diene complex 1 (3.3 g, 5 × 10
butadiyne (2 g, 1 × 10 mol), and 200 mg of CuCl in toluene
20 mL) was heated at 60 °C for 5 h. After evaporation, the
residue was chromatographed on silica gel with hexane/CH
Cl as the eluent. The first fraction was eluted with hexane;
00 mg of diyne in excess was recovered. The second fraction
was eluted with hexane/CH Cl (10/1); 1.7 g of phosphirene 3
was isolated as a light yellow powder (yield 55%): P NMR
mol), 1,4-diphenyl-1,3-
-
2
(
2
-
2
7
2
2
3
1
1
(
CDCl
3
) δ -133.99 ( J (P-W) ) 273.8 Hz); mass m/z (relative
intensity) 638 (M , 12), 578 (M - 2CO, 8), 550 (M - 3CO,
+
+
+
hindered and more stable trans stereoisomers. Our
+
+
1
9), 522 (M - 4CO, 29), 494 (M - 5CO, 100). Anal. Calcd
for C27 PW: C, 51.10; H, 2.36. Found: C, 50.39; H, 2.41.
The third fraction was eluted with hexane/CH Cl (10/2);
00 mg of 1,2-dihydro-1,2-diphosphete 4 was obtained and
characterized as described hereafter.
1,2,3-Tr iph en yl-4-ph en eth yn yl-1,2-dih ydr o-1,2-diph os-
proposal is summarized in Scheme 1. The activated
15 5
H O
1
2
C dC double bond of the phosphirene ring is attacked
2
2
2
by the incoming phosphinidene at the less hindered C .
1
1
The structural data show (Figure 2) that W is farther
2
1
1
2
away from C than R : W ‚‚‚C separation of 3.753 vs
[
1
5
2
2
.955 Å for R (C )‚‚‚C . Hence, the attack takes place
p h ete]d eca ca r bon yld itu n gsten (4). A solution of phos-
1
-3
on the W side of the phosphirene ring. The orientation
phirene complex 3 (1 g, 1.57 × 10 mol), 7-phosphanorbor-
2
1
-3
of the phosphinidene places W away from W . Phos-
phirane carbocations are known to ring-open easily.
nadiene complex 1 (1 g, 1.5 × 10 mol), and 60 mg of CuCl in
1
1
toluene (10 mL) was heated at 60 °C for 3 h. After evaporation,
the residue was chromatographed on silica gel with hexane/
CH Cl (10/2) as the eluent; 300 mg of phosphirene complex 3
2 2
were recovered, and then 1 g of complex 4 was isolated as
yellow powder (yield 60%, based on the phosphirene con-
In our case, the opening of the phosphirane carbocation
resulting from the initial attack places the two phos-
phorus atoms face to face with the required stereochem-
istry.
31
sumed): P NMR (CDCl
3
) δ 38.88 and 41.16 (∑J (P-P) ) 33.85
This series of reactions opens a new, convenient, and
rather general access to symmetrically or unsymmetri-
cally substituted cis-1,2-dihydro-1,2-diphosphetes. More-
over, it should be possible to introduce functional groups
13
2
3
Hz); C NMR (CDCl ) δ 86.92 (dd, J (C-P) ) 21.9 Hz, J (C-
3 4
3
P) ) 8.6 Hz, CtCPh), 103.06 (pseudotriplet, J (C-P) ≈ J (C-
1
2
P) ≈ 3.0 Hz, CtC-Ph), 154.28 (dd, J (C-P) ) 33.1 Hz, J (C-
2
P) ) 15.1 Hz, CdC), 196.49 (d, J (C-P) ) 6.2 Hz, CO cis),
1
2
2
on the phosphorus atoms such as alkoxy, alkoxycar-
198.99 (d, J (C-P) ) 27.2 Hz, CO trans); mass m/z (relative
+
+
+
1
3
14
15
intensity) 1066 (M , 35), 982 (M - 3CO, 72), 870 (M - 7CO,
bonyl, dialkylamino, and vinyl from the appropriate
phosphinidene precursors, thus broadening the scope of
this method.
+
9
6), 786 (M - 10CO, 100). Anal. Calcd for C38
C, 42.77; H, 1.8. Found: C, 42.83; H, 2.01.
H
20
O
10
P
2
W
2
:
[
1-Meth yl-2,3-d ip h en yl-4-p h en eth yn yl-1,2-d ih yd r o-1,2-
d ip h osp h ete]d eca ca r bon yld itu n gsten (6). A solution of
Exp er im en ta l Section
-3
phosphirene complex 3 (0.3 g, 0.5 × 10 mol), 7-phosphanor-
-3
bornadiene complex 5 (1 g, 1.6 × 10 mol), and 60 mg of CuCl
All reactions were performed under nitrogen; the solvents
were purified, dried and degassed by standard techniques. H,
C, and P NMR spectra were recorded on a Bruker AC 200
in toluene (10 mL) was heated for 2.5 h. The same purification
1
3
1
as above gave 300 mg of 6 as a yellow powder (yield 60%):
NMR (CDCl ) δ 25.96 (d, ∑J (P-P) ) 29.22 Hz, P-Me), 34.67
d, P-Ph); H NMR (CDCl ) δ 1.56 (pseudotriplet, 3H, Me), 7.55
P
1
3
31
3
SY spectrometer operating at 200.13, 50.32, and 81.01 MHz,
respectively. All chemical shifts are reported in ppm downfield
1
(
(
3
1
3
1
m, 18H, Ph); C NMR (CDCl
3
) δ 21.66 (d, J (C-P) )7.4 Hz,
3
1
13
31
3 4
from internal TMS ( H and C) and external 85% H PO ( P).
CH
-
,
3
), 85.42 (dd, 2J (C-P) ) 23.1 Hz, J (C-P) ) 9.0 Hz,
Mass spectra (EI) were obtained at 70 eV by the direct inlet
method.
1,2-Diph en yl-3-(ph en oxypr opyn yl)-4-(ph en oxym eth yl)-
,2-dih ydr o-1,2-diph osph ete]decacar bon ylditu n gsten (2).
3
4
CtCPh), 102.45 (pseudotriplet, J (C-P) ≈ J (C-P) ≈ 3.3 Hz
-CtCPh), 151.14 (dd, 1J (C-P) ) 33.3 Hz, 2J (C-P) ) 14.4
[
Hz, CdC), 196.08 (d, CO cis), 198.20 (d, CO trans); mass m/z
relative intensity) 1004 (M , 15), 920 (M - 3CO, 45), 864
1
+
+
(
(
A solution of 7-phosphanorbornadiene complex 1 (3.3 g, 5 ×
+
+
+
M - 5CO, 32), 808 (M - 7CO, 81), 724 (M - 10CO, 100).
: C, 39.44; H, 1.79. Found: C,
-
3
-3
1
0
mol), 1,6-diphenoxy-2,4-hexadiyne (2 g, 7.6 × 10 mol),
Anal. Calcd for C33
0.13; H, 1.67.
1-Ben zyl-2,3-d ip h en yl-4-p h en eth yn yl-1,2-d ih yd r o-1,2-
d ip h osp h ete]d eca ca r bon yld itu n gsten (8). Same proce-
18 10 2 2
H O P W
and 200 mg of CuCl as a catalyst in toluene (20 mL) was
heated at 60 °C for 10 h. After evaporation, the residue was
chromatographed on silica gel (70-230 mesh Merck) with
4
[
hexane/CH
2 2
Cl as the eluent; 1.7 g of 2 was isolated as a dark
3
1
dure as above with 7 (yield 60%): P NMR (CDCl
3
) δ 39.80
d, ∑J (P-P) ) 35.86 Hz), 41.69 (d); C NMR (CDCl ) δ 41.2
Ph), 86.38 (dd, J (C-P) ) 21.7 Hz, J (C-P) ) 9.2 Hz,
3
1
orange powder (yield 47%):
P NMR (CDCl
3
) δ 43.88 (d,
) δ 4.7 (s, 4H,
) δ 56.41 (s,
1
3
(
(
3
1
∑
CH
CH
J (P-P) ) 28 Hz), 49.37 (d); H NMR (CDCl
3
2
3
s, CH
2
1
3
2
OPh), 6.9-7.3 (m, 20H, Ph); C NMR (CDCl
3
1
-
CtCPh), 102.8 (s, -CtCPh), 151.05 (dd, J (C-P) ) 32.4 Hz,
2
2
2
) , 66.77 (d, J (C-P) ) 4.4 Hz , CH
21.3 Hz, J (C-P) ) 9.1 Hz, -CtCsCH
2
), 81.11 (dd, J (C-P)
2
J (C-P) ) 15.0 Hz, CdC); mass m/z (relative intensity) 1080
3
3
)
2
OPh), 98.87 (d, J (C-
+
+
+
+
(
8
O
M , 6), 996 (M - 3CO, 26), 912 (M - 6CO, 29), 856 (M -
1
P) ) 3.3 Hz, -CtCsCH
2
OPh), 156.56 (dd, J (C-P) ) 30.5 Hz,
+
CO, 32), 800 (M - 10CO, 100). Anal. Calcd for C39
H
22
-
2
2
J (C-P) ) 16.8 Hz, CdC), 195.26 (d, J (C-P) ) 6.3 Hz , CO
P
2
W
2
: C, 43.33; H, 2.02. Found: C, 42.62; H, 2.09.
2
10
cis), 198.2 (d, J (C-P) ) 18.2 Hz, CO trans); mass, m/z (relative
[
1-Allyl-2,3-d ip h en yl-4-p h en et h yn yl-1,2-d ih yd r o-1,2-
d ip h osp h ete]d eca ca r bon yld itu n gsten (10). Same proce-
(
11) Tran Huy, N. H.; Mathey, F. Synlett. 1995, 353.
3
1
dure as above with 9 (yield 60%): P NMR (CDCl
3
) δ 35.52
(12) Alcaraz, J .-M.; Svara, J .; Mathey, F. Nouv. J . Chim. 1986, 10,
1
3
21.
(
(
(d, ∑J (P-P) ) 35.8 Hz), 38.36 (d); H NMR (CDCl
H, PCH -), 5.2-5.6 (m, 3H, -CHdCH ), 7.6 (m, 15H, Ph);
NMR (CDCl ) δ 40.82 (s , -CH -), 86.23 (dd, J (C-P) ) 21.3
Hz, J (C-P) ) 9.3 Hz, -CtCPh), 102.77 (pseudotriplet, J (C-
3
) δ 2.7 (m,
13) Holand, S.; Mathey, F. Organometallics 1988, 7, 1796.
14) (a) Deschamps, B.; Ricard, L.; Mathey, F. Polyhedron 1989, 8,
13
2
2
2
C
2
3
2
2
671. (b) Deschamps, B.; Mathey, F. Synthesis 1995, 941.
15) Tran Huy, N. H.; Ricard, L.; Mathey, F. Organometallics 1991,
0, 3958.
3
3
(
4
1
1
P) ≈ J (C-P) ≈ 3.4 Hz, -CtCPh), 151.37 (dd, J (C-P) ) 33.3

4
504 Organometallics, Vol. 16, No. 20, 1997
Notes
(M+ - 3CO, 23), 834 (M - 7CO, 49), 778 (M+ - 9CO, 53),
+
Ta ble 1. Ta ble of Cr ysta llogr a p h ic Da ta
+
7
50 (M - 10CO, 100).
3
8
X-r a y Str u ctu r e Deter m in a tion s. All data sets were
formula
space group
data collection temp (K)
a (Å)
b (Å)
c (Å)
C28H15O5PW C39H22O10P2W2
collected on an Enraf Nonius CAD4 diffractometer using Mo
KR (λ ) 0.710 73 Å) and a graphite monochromator. The
crystal structures were solved by direct methods (SIR92) and
refined with the Enraf Nonius OpenMOLEN package using
reflexions having F2 < 3.0σ(F2). The hydrogen atoms were
included as fixed contributions in the final stages of least-
squares refinement while using anisotropic temperature
factors for all other atoms. Crystal data are assembled in
Table 1.
P 1h (No. 2)
123
P21/n (No. 14)
123
10.249(2)
11.856(2)
12.422(2)
101.92(3)
108.93(2)
100.85(1)
1342.0(1)
2
15.666(2)
12.488(2)
19.927(4)
R (deg)
â (deg)
γ (deg)
110.34(1)
3
V (Å )
3655.0(2)
4
Z
3
dcalc (g/cm )
1.598
44.8
1.963
65.7
-
1
µ (cm
)
Ack n ow led gm en t. The authors thank the CNRS
and Ecole Polytechnique for financial support.
max 2θ
60.0
52.6
no. of reflns measd
no. of reflns included
no. of params refined
unweighted agreement factor
weighted agreement factor
GOF
8219
6429
327
8014
4485
479
Su p p or tin g In for m a tion Ava ila ble: X ray structure
determination for 3 and 8, including tables of positional
parameters, bond distances and angles for non-hydrogen
atoms, and âij values (8 pages). Ordering information is given
on any current masthead page.
0.028
0.034
1.09
0.030
0.029
1.01
convergence, largest shift/error 0.03
0.00
2
Hz , J (C-P) ) 13.8 Hz, CdC), 196.17 (m, CO cis), 197.84 (m,
+
CO trans); mass: m/z (relative intensity) 1030 (M , 8), 946
OM970487T