Synthesis of the first chiral phosphorous chelate aminophosphino-carbene complex and its applications in stereoselective addition reactions

Article abstract of DOI:10.1016/S0020-1693(99)00372-2

The first phosphorous chelate chiral aminophosphinomethyl carbene complex 5 has been synthesized. Its conjugated base represents a new chiral α-unsubstituted amide enolate equivalent for stereo selective addition reactions. The structure of the major diastereoisomer of the aldol addition complex between 5 and pO₂N-C₆H₄-CHO, solved by X-ray diffraction, shows that the (S)-enantiomer of the conjugated base of 5 reacts preferentially with the re face of the carbonyl function.

Full text of DOI:10.1016/S0020-1693(99)00372-2

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Inorganica Chimica Acta 296 (1999) 236–245
Synthesis of the first chiral phosphorous chelate
aminophosphino–carbene complex and its applications in
stereoselective addition reactions
Stefano Maiorana a,*, Antonio Papagni b,1, Emanuela Licandro a, Dario Perdicchia a,
Clara Baldoli c, Claudia Graiff d, Antonio Tiripicchio d
a Dipartimento di Chimica Organica e Industriale, Uni6ersita’ degli Studi di Milano, 6ia Golgi 19, I-20133 Milan, Italy
b Dipartimento di Scienza dei Materiali, Uni6ersita’ degli Studi di Milano ‘Bicocca’, 6ia Cozzi 53, I-20125 Milan, Italy
c Centro Studio Sintesi e Stereochimica Speciali Sistemi Organici del CNR 6ia Golgi 19, I-20133 Milan, Italy
d Dipartimento di Chimica Generale ed Inorganica, Chimica Analitica, Chimica Fisica, Uni6ersita` di Parma,
Centro di Studio per la Strutturistica Diffrattometrica del CNR, Viale delle Scienze, I-43100 Parma, Italy
Received 24 June 1999
Abstract
The first phosphorous chelate chiral aminophosphinomethyl carbene complex 5 has been synthesized. Its conjugated base
represents a new chiral a-unsubstituted amide enolate equivalent for stereoselective addition reactions. The structure of the major
diastereoisomer of the aldol addition complex between 5 and pO2NꢀC6H4ꢀCHO, solved by X-ray diffraction, shows that the
(S)-enantiomer of the conjugated base of 5 reacts preferentially with the re face of the carbonyl function. © 1999 Elsevier Science
S.A. All rights reserved.
Keywords: Carbene complexes; Diastereoselective aldol additions; Intramolecular phosphorous coordination
1. Introduction
and good/excellent stereoselectivities have been ob-
tained with cyclic enones [4a,b] and nitroolefins [5]
using the chiral aminocarbene complexes 1 and 2 (Fig.
1).
Ever since their first preparation [1], Fischer-type
carbene complexes have continued to reveal their par-
ticular and highly interesting chemical behavior, and
are now routinely used as versatile organometallic
reagents in organic synthesis [2]: for example, they can
be used in both metal-centered cycloaddition reactions
(i.e. benzannulation or cyclopropanation reactions) [2]
and in carbene-centered reactions, in which exploitation
of the reactivity of anions on the a-carbon atom (easily
generated by treatment with bases) makes it possible to
prepare differently functionalized carbene complexes
[3]. The possibility of using them as chiral enol–acetate
equivalents in stereoselective CꢀC bond formation in
Michael addition reactions has also been envisaged,
The immobilization of a portion of the organic car-
bene ligand by means of chelation to the metal [6] is a
recently introduced strategy in Fischer carbene chem-
istry which often profoundly modifies reactivity and
allows many processes to be performed stereoselectively
under milder conditions. The high levels of diastereose-
lection obtained in both aldol and Michael addition
reactions by using the chiral chelated aminocarbene
complex 3 [7,8] is a recent example of the application of
this strategy (Fig. 1)2,3
.
Double bonds [10], sulfur [11] or phosphorous atoms
[12] present in the carbenic ligand can be easily coordi-
nated to the metal when placed at the right distance;
furthermore, we have recently reported [13] that the
nitrogen atom of hydrazinocarbenes can be easily coor-
dinated to the metal to afford highly stable four-mem-
bered ring chelate complexes.
* Corresponding author. Tel.: +39-02-266 3978; fax: +39-02-236 4369.
E-mail address: maior@icil64.cilea.it (S. Maiorana)
1 Also corresponding author. antonio.papagni@mater.unimi.it.
0020-1693/99/$ - see front matter © 1999 Elsevier Science S.A. All rights reserved.
PII: S0020-1693(99)00372-2

S. Maiorana et al. / Inorganica Chimica Acta 296 (1999) 236–245
237
of conformationally rigid chiral aminocarbene com-
plexes. The complexes 4 were expected to have advan-
tages over simple aminocarbenes or complex 3, at least
in terms of the reactivity of the corresponding conju-
gated base, because it has been reported [14] that the
replacement of a CO ligand by a lower p-accepting
phosphine in Fischer-type carbene complexes leads to a
considerable reduction in the hydrogen acidity on the
a-carbon atom at the carbenic center. Consequently,
there is an increase in the nucleophilicity of the corre-
sponding conjugated bases in their reactions with elec-
trophiles. Furthermore, the presence in 4 of the
magnetic spin active phosphorous atom introduces an
additional parameter that may be useful in analysing
the stereochemical outcome of stereoselective processes.
We report here the synthesis of the first chiral phos-
phorous-chelate aminophosphinocarbene complex 5,
the generation of its conjugated base, and some prelim-
inary results concerning its use in stereoselective pro-
cesses (Fig. 2).
Fig. 1.
2. Results and discussion
Complex 5 was synthesized in racemic form by
means of aminolysis of the methoxymethylcarbene
complex 6 with aminophosphine 7 in THF at −78°C.
The aminophosphinocarbene complex 8, obtained as a
3:1 E/Z mixture without any purification4, was heated
for 30 min in refluxing toluene to give the chelate
complex 9 in an overall yield of 63% (from 7). Finally,
the nitrogen atom was methylated under phase transfer
conditions to afford 5 in 93% yield (Scheme 1).
The great potential offered by intramolecular coordi-
nation (especially in stereoselective processes) prompted
us to investigate the process in more detail by extending
it to different heteroatoms with the aim of preparing
new chiral amino carbene complexes and exploiting
them in stereoselective syntheses.
In particular, we concentrated on phosphorous atom
chelate aminophosphinocarbene complexes with the
general structure 4 (Fig. 2), which represent a new class
4 The E and Z isomers of complex 8 can be separated by means of
column chromatography. However both pure isomers were found to
evolve into a 3:1 E/Z mixture (Z more rapidly) when left standing in
a solution and dry state, and this hampers their full spectroscopic
characterization. Furthermore, atmospheric oxygen must be carefully
excluded in all manipulations of this complex in order to avoid the
easy oxidation of the phosphine function to a phosphinoxide func-
tion.
Fig. 2.
2 The diastereoisomeric excess is almost always found on the
corresponding a-hydroxyamides: i.e. after the removal of the metal-
carbonyl moiety by oxidation with Ce+4 salts. Since the recovered
organic material from this oxidation never reached 100; the reported
diastereoselectivities represent only a qualitative and not a quantita-
tive evaluation of the stereochemical outcome of the aldol addition
process. D.e. has been evaluated using another chelated imidazolidi-
none complex on the aldol addition complex with a silylated hydroxy
function; the absolute configuration of the new stereocenter of this
latter complex has also been determined by X-ray analysis [8].
3 Complex 1 has also been used in aldol addition reactions, but
with modest or no diastereoselection [9]. Complex 2 was reacted with
p-NO2-benzaldehyde giving the corresponding aldol addition product
in 67% yield and as a 1:1 diastereoisomeric mixture. (d.e. evaluated
by 1H NMR on aromatic hydrogen ortho to the carbinolic function).
Scheme 1. (i) THF, −78°C, 5 h; (ii) toluene reflux, 45 min; (iii) MeI
(50 equiv.), benzene, NaOH 50; TBAB, 20 min.

238
S. Maiorana et al. / Inorganica Chimica Acta 296 (1999) 236–245
Complex 5 is remarkably stable to air and silica gel,
with a stability that is comparable with or better than
that of simple aminocarbene complexes. The treatment
of 5 with n-BuLi in THF at −78°C easily generates the
corresponding conjugated base, and its reactivity was
investigated in reactions with electrophiles (Table 1).
Various types of electrophiles were considered: alky-
lating reagents, aromatic and aliphatic aldehydes (linear
and a-branched), and electron-poor olefins such as
b-nitrostyrene and 2-cyclohexene-1-one. All of these
electrophiles led to good reactivity at −78°C of the
conjugated base of 5 to afford adducts 10 in good to
excellent yields, with a conversion of over 90% in
almost all cases (Table 1). A new stereocenter is pro-
duced in entries 2–10: the observed diastereoselectivi-
ties were fair to good with aromatic aldehydes (entries
2–5), and moderate with linear and a-branched alde-
hydes and in Michael reaction with 2-cycloexene-1-one
(entries 6–8 and 10). No diastereoselection was ob-
served with nitrostyrene (entry 9). In all cases, the
diastereoselection could be easily determined on the
crude reaction mixture by integrating the well-separated
31P resonance signals for each diastereoisomers, and the
resonances of the two aromatic hydrogen atoms falling
within the range of 6.7–6.2 ppm were also particularly
diagnostic.
Scheme 2.
The reaction with isobutyrraldehyde was also per-
formed at −100°C in order to check whether the
diastereoselection was affected by temperature (entry 8,
Table 1
Reaction of the complex 5 with electrophiles a,b
Entry
Electrophile
R
Temp. (°C)
Time (min)
Yield a (%)
D.e. b (%)
31P NMR (ppm)
major
75.19
minor
78.33
1
2
3
4
5
6
7
8
9
BnBr
a: Bn–
−78
−78
−78
−78
−78
−78
−78
−100
−78
200
5
30
200
200
200
200
200
200
85(5)
80(1)
78(5)
73(15)
85(10)
62(37)
76(20)
88(7)
–
75.43
Ph–CHO
Ph–CHO
Ph–CHO
b: Ph–CH(OH)–
Ph–CH(OH)–
Ph–CH(OH)–
60
60
60
74
34
44
40
0
pNO2C6H4–CHO c: pNO2C6H4–CH(OH)–
73.26
74.79
75.17
78.03
78.77
78.71
EtCHO
iPrCHO
iPrCHO
d: EtCH(OH)–
e: iPrCH(OH)–
iPrCH(OH)–
85(6)
68.53
75.31
78.46
76.87
10
−78
200
92(2)
34
a Yields on isolated compounds. Between brakets recovering of unreacted 5.
b D.e. evaluated on the crude reaction mixture by 1H NMR and by 31P NMR.

S. Maiorana et al. / Inorganica Chimica Acta 296 (1999) 236–245
239
Fig. 3. ORTEP view of the structure of the (SC17,RC28)-enantiomer of the complex 10c together with the atomic numbering scheme. The ellipsoids
for the atoms are drawn at 30% probability level.
Table 1): the aldol addition complex was recovered
with the the same level of diastereoselection as that
observed at −78°C, but with a considerable improve-
ment in chemical yield (88% versus 76%).
in Table 2. The coordination around Cr is distorted
octahedral with the organic moiety acting as a chelating
ligand through the P1 and C26.
The six-membered chelation ring shows an envelope
,
confomation with C24 out by 0.85(1) A from the mean
We have investigated the effect of the reaction time
in the aldol addition process using benzaldehyde. By
monitoring its reaction with 5 at different times (5, 30,
200 min, entries 2–4), it was possible to see that the
addition of the conjugated base of 5 to the aldehyde is
very fast (pratically complete within 5 min, with the
plane through the other five atoms, the chelation
Table 2
,
Selected bond lengths (A) and angles (°) for 10c·0.75CH2Cl2
Cr(1)ꢀC(26)
Cr(1)ꢀP(1)
P(1)ꢀC(17)
O(5)ꢀC(28)
N(1)ꢀC(26)
N(1)ꢀC(25)
N(1)ꢀC(24)
N(2)ꢀC(32)
C(17)ꢀC(24)
C(26)ꢀC(27)
C(27)ꢀC(28)
C(28)ꢀC(29)
2.121(6)
2.379(2)
1.858(6)
1.421(7)
1.314(7)
1.472(8)
1.490(8)
1.471(9)
1.543(9)
1.519(8)
1.531(9)
1.520(9)
1
unreacted 5 analyzed by H NMR being less than 1%)
and that, after the addition, equilibrium of the aldolate,
the conjugated base of 5, and the starting aldehyde
seems to take place. These results, together with those
obtained at different temperature, strongly suggest the
reversibility of the aldol addition process, in which both
temperature and reaction times play an important role
in determining the chemical yields of aldol complexes
10 without affecting the diastereoselection (Scheme 2).
In the case of complex 10c, we were able to isolate a
pure sample of major diastereoisomer by means of
preparative thin layer chromatography. Crystallization
from dichloromethane/pentane affords crystals of the
dichloromethane solvate of 10c suitable for X-ray anal-
ysis. Because of the presence of an inversion center in
the crystal structure the major diastereoisomer is
present in both (R,S) or (S,R) configurations. Disor-
dered molecules of dichloromethane are also present in
the crystals.
C(26)ꢀCr(1)ꢀP(1)
C(17)ꢀP(1)ꢀCr(1)
C(26)ꢀN(1)ꢀC(25)
C(26)ꢀN(1)ꢀC(24)
C(25)ꢀN(1)ꢀC(24)
C(24)ꢀC(17)ꢀP(1)
N(1)ꢀC(24)ꢀC(17)
N(1)ꢀC(26)ꢀC(27)
N(1)ꢀC(26)ꢀCr(1)
C(27)ꢀC(26)ꢀCr(1)
C(26)ꢀC(27)ꢀC(28)
O(5)ꢀC(28)ꢀC(29)
O(5)ꢀC(28)ꢀC(27)
C(29)ꢀC(28)ꢀC(27)
91.44(18)
111.7(2)
128.1(5)
121.6(5)
110.3(5)
106.4(4)
112.2(5)
114.1(5)
128.1(4)
117.6(4)
111.8(5)
110.7(6)
110.6(5)
112.0(5)
The structure of the (S,R) enantiomer of 10c is
shown in Fig. 3 together with the atomic numbering
system and selected bond distances and angles are given

240
S. Maiorana et al. / Inorganica Chimica Acta 296 (1999) 236–245
formed stereocenter is, in almost all cases, opposite to
that present in the aminophosphino moiety.
4. Experimental
4.1. General
The amino phosphine 7 and complex 6 were prepared
using standard procedures [16,17]. The aliphatic alde-
hydes, benzaldehyde and 2-cyclohexene-1-one were pur-
chased from Aldrich and distilled just before use; the
para-nitrobenzaldehyde and b-nitrostyrene were pur-
chased from Aldrich and used as received. The reagent
n-BuLi (1.6 M hexane solution) was purchased from
Merck and titred just before use. THF was dried by
refluxing over Na/benzophenone ketyl. All of the ma-
nipulations were made under an inert atmosphere.
Flash and dry chromatography were performed using
silica gel 60 Merck 230–400 mesh. The melting points
were measured using a Bu¨chi 510 melting point appara-
tus and are uncorrected. The IR spectra were recorded
on a Perkin–Elmer 1725X FT-IR spectrometer, and the
NMR spectra were obtained using a Bruker AMX 300
and AC300; mass spectra (EI, FAB) were collected
using a VG Analytical 7070 EQ instrument.
Fig. 4. Stereochemical model for the reaction between the conjugated
base of (S)-5 and aldehydes.
P1Cr1C26 angle being 91.44(18)°. The Cr1ꢀC26,
,
,
2.121(6) A, and C26ꢀN1, 1.314(7) A, bond lengths fall
,
in the average values [(2.102(8) and 1.321(7) A] found
for the CrꢀC and CꢀN bond lengths in the CrꢀCꢀN
fragments of aminocarbene complexes [15].
The X-ray analysis has confirmed the chelated nature
of complex 5 and clearly shows that the major (S,R)
diastereoisomer produced in the aldol addition process
has originated by reaction of the (S)-enantiomer of 5
with the re face of the carbonyl function. It is likely
that the configuration of the major diastereoisomer of
aldol complexes 10b and 10e is also (S,R) [or (R,S)],
and that of complex 10d is (S,S) [or (R,R)]. In fact, the
diastereoisomer nature of the above complexes can be
inferred by comparison of their 31P and 1H NMR
spectra with those of 10c. X-ray analysis also shows
two phenyl substituents (one bound to phopshorous
atom and the other on the stereogenic center of the
aminophospine moiety) shielding the bottom face of the
chelate six-membered ring in its envelope conformation.
If the conjugated base of 5 keeps in solution the same
conformation, the approach of the aldehyde must pref-
erentially occur from the opposite side of the two
phenyl rings and with the bulky substituent far from
the tetracarbonylchromium moiety. In Fig. 4, the ap-
proaching model of aldehydes to the conjugated base of
the (S)-5 enantiomer is represented.
4.2. Synthesis of complex 9
The aminophosphine 7 (4.4 mmol dissolved in 5 ml
of dry THF) was added in 5 min to a THF solution (30
ml) of 6 (4 mmol) cooled to −78°C. The mixture was
allowed to react for 5 h at −78°C, then the solvent was
removed under reduced pressure to afford a crude
reaction mixture containing complex 8 as the main
1
reaction product (E/Z mixture, 3:1 ratio by H NMR
analysis). The crude reaction mixture was dissolved in
dry toluene and refluxed for 45 min. The solvent was
removed under reduced pressure and the dark orange
oil purified by means of dry column chromatography
(eluent: light petroleum/methylene chloride, 3:2) to af-
ford 9 in 63% yield (based on starting complex 6).
Complex 9: yellow solid, m.p. 71°C (from methylene
chloride/pentane). IR (Nujol) cm−1: 3295 (wNꢀH);
1995 (wCO trans), 1989–1850 (broad, wCO cis).
1H NMR (300 MHz, CDCl3) l ppm: 2.89 (s, 3H,
CH3–CꢁCr), 3.68 (m, 1H, Ph2PꢀCHꢀCH2ꢀN), 4.10 [m,
1H, Ph2PꢀCHꢀC(H)HꢀN], 4.40 [m, 1H, Ph2PꢀCHꢀ
CH(H)ꢀN], 6.57 (d, 2H arom, Jortho=7.6 Hz), 6.90–
7.40 (m, 13H arom), 9.17 (bs, 1H, NH). 13C NMR
(75 MHz, CDCl3) l ppm: 39.97 (Ph2PꢀCH+CrꢁCꢀ
CH3), 56.12 (d, Ph2PꢀCHꢀCH2ꢀN, JP–C=12.7 Hz),
126.37 (CH, arom), 126.74 (CH, arom), 128.09 (CH,
arom), 128.25 (CH, arom), 128.60 (CH, arom), 129.97
(CH, arom), 130.10 (CH, arom), 131.72 (d, Cq,
3. Conclusions
We report here the synthesis of the first stable and
chiral intramolecularly phosphorous chelated amino-
carbene complex, and the generation and reactivity of
the corresponding conjugated base towards elec-
trophiles. These preliminary results indicate the better
reactivity of this complex in comparison with simple
aminocarbene complexes. The diastereoselectivity ob-
served in aldol addition reaction were good only in the
case of aromatic aldehydes, but it is likely that these
can be improved by modifying the substitution pattern
in the starting aminophosphine. In the case of an aldol
addition reaction, the configuration of the newly
JP–C=30.5 Hz), 135.51 (CH, arom), 138.09 (Cq),

S. Maiorana et al. / Inorganica Chimica Acta 296 (1999) 236–245
241
139.75 (d, Cq, JP–C=32.0 Hz), 217 (bs, CO), 225 (bs,
CO), 230 (bs, CO), 232 (bs, CO), 285 (bs, CrꢁCꢀC). 31P
NMR (121 MHz, CDCl3, H3PO4 as external standard)
l ppm: 68.96. Anal. Found: C, 62.87; H, 4.29; N,
2.71%. Calc. for C26H22CrNO4P, MW 495.44: C, 63.03;
H, 4.48; N, 2.83%.
base of complex 5 (generated by treating 1 mmol of 5
with 0.7 ml of 1.6 M hexane solution of n-BuLi (1.1
mmol) at −78°C for 20 min) under an inert atmo-
sphere. The mixture was allowed to react at −78°C
and the progress of the reaction was monitored by TLC
analysis (eluent: CH2Cl2/light petroleum 1:1). After the
time reported in Table 1, the reaction was considered
concluded. The reaction was quenched by adding 10 ml
of a saturated ammonium chloride solution, followed
by extraction with CH2Cl2 (2×50 ml). The organic
phase was dried over Na2SO4, and the solvent was
evaporated under reduced pressure. The crude reaction
mixture was purified by means of dry flash chromatog-
raphy (eluent: light petroleum/methylene chloride, 3:2)
to afford complexes 10a–g (see Table 1 for yields). The
diasteroisomeric mixture of complexes 10b and d–g
were unseparable using classical techniques. The pure
major diastereoisomer of complex 10c was obtained by
means of preparative TLC (eluent: light petroleum/
ethylacetate, 3:2) and crystallized from methylene
chloride/pentane.
4.3. Synthesis of the complex 5
NaOH 50% (6 ml) and tertrabutylammonium bro-
mide (0.8 mmol) were added at room temperature to a
benzene solution (30 ml) of 9 (4.2 mmol). Under vigor-
ous stirring, MeI (50 mmol) was introduced by means
of a syringe, and the mixture was allowed to react at
room temperature. The reaction, which was monitored
by means of TLC analysis (eluent: light petroleum/
methylene chloride, 3:2), was completed after 30 min
and quenched by adding water (10 ml); the organic
solvent was removed under reduced pressure. The re-
sulting suspension was extracted with methylene chlo-
ride (2×20 ml), and the organic phase was washed
with water (2×10 ml), dried over Na2SO4 and the
solvent evaporated under reduced pressure. The crude
reaction mixture was purified by means of dry column
chromatography (eluent: light petroleum/methylene
chloride, 3:2) to afford complex 5 in 93% yield.
Complex 10a: yellow solid, m.p. 211°C (dec.) (from
methylene chloride). IR (Nujol) cm−1: 1996 (wCO
trans), 1897–1830 (broad, wCO cis). 1H NMR (300
MHz, CDCl3) l ppm: 2.70 [dt, 1H, Jgem=Jvic1=12.5
Hz, Jvic2=5.4 Hz, PhꢀC(H)HꢀCH2ꢀCꢁCr], 2.90 [dt,
1H, Jgem=Jvic1=12.5 Hz, Jvic2=5.2 Hz, PhꢀCH(H)ꢀ
Complex 5: yellow solid, m.p. 95°C (from toluene,
the complex crystallized incorporating a molecule of
toluene), m.p. 158°C (from methylene chloride/pen-
tane). IR (Nujol) cm−1: 1994 (wCO trans), 1986–1833
CH2ꢀCꢁCr], 3.31 (s, 3H, NCH3), 3.40 [dt, 1H, Jgem
vic1=12.5 Hz, Jvic2=5.4 Hz, PhꢀCH2ꢀC(H)HꢀCꢁCr],
=
J
3.50 [dt, 1H, Jgem=Jvic1=12.5 Hz, Jvic2=5.2 Hz,
PhꢀCH2ꢀCH(H)ꢀCꢁCr], 3.70 [m, 1H, Ph2PꢀCHꢀ
CH2ꢀN], 4.10 [m, 1H, Ph2PꢀCHꢀC(H)HꢀN], 4.78 [m,
1H, Ph2PꢀCHꢀCH(H)ꢀN], 6.60 (d, 2H arom, Jortho=6
Hz), 6.90–7.40 (m, 18H arom). 13C NMR (75 MHz,
CDCl3) l ppm: 31.64 (CrꢁCꢀCH2ꢀCH2ꢀPh), 39.38
(Ph2PꢀCHꢀCH2), 43.23 (NꢀCH3), 54.50 (CrꢁCꢀCH2ꢀ
CH2ꢀPh), 65.04 (d, Ph2PꢀCHꢀCH2ꢀN, JP–C=14 Hz),
126.41, 126.52, 127.48, 127.61, 128.29, 128.83, 129.96,
130.25, 135.50, 135.63 (CH, arom), 137.33 (Cq), 138.47
(Cq), 131.24 (d, Cq, JP–C=30 Hz), 140.38 (d, Cq,
1
(broad, wCO cis). H NMR (300 MHz, CDCl3) l ppm:
2.82 (s, 3H, CH3ꢀCꢁCr), 3.29 (s, 3H, NCH3), 3.76 [m,
1H, Ph2PꢀCHꢀCH2ꢀN], 4.22 [ddd, 1H, JPꢀH=29 Hz,
J
gem=13.5 Hz, Jvic=2.1 Hz, Ph2PꢀCHꢀC(H)HꢀN],
4.78 [m, 1H, Ph2PꢀCHꢀCH(H)ꢀN], 6.68 (d, 2H arom,
ortho=6 Hz), 6.90–7.40 (m, 13H arom), 9.17 (bs, 1H,
J
NH). 13C NMR (75 MHz, CDCl3) l ppm: 39.60
(CrꢁCꢀCH3), 39.72 Ph2PꢀCHꢀCH2), 48.84 (NꢀCH3),
65.30 (d, Ph2PꢀCHꢀCH2ꢀN, JP–C=13.9 Hz), 126.57
(CH, arom), 127.57 (CH, arom), 128.34 (CH, arom),
128.52 (CH, arom), 128.73 (CH, arom), 129.90 (CH,
arom), 130.09 (CH, arom), 132.29 (d, Cq, JP–C=32
Hz), 135.61 (CH, arom), 138.16 (Cq), 140.43 (d, Cq,
JP–C=35 Hz), 220.03 (CO), 224.60 (CO), 229.03 (CO),
230.05 (CO), 281.50 (CrꢁCꢀC). 31P NMR (121 MHz,
CDCl3, H3PO4 as external standard) l ppm: 75.43.
Anal. Found: C, 67.89; H, 5.02; N, 2.15%. Calc. for
C34H30CrNO4P, MW 599.58: C, 68.11; H, 5.04; N,
2.34%.
JP–C=35 Hz), 219.79 (CO), 224.53 (CO), 229.17 (CO),
230.14 (CO), 282.89 (CrꢁCꢀC). 31P NMR (121 MHz,
CDCl3, H3PO4 as external standard) l ppm: 73.89. MS
(EI) m/z: 509 (M+), 453 (M+−2CO), 425 (M+
−3CO), 397 (M+−4CO), 345 (M+−4COꢀCr). Anal.
Found: C, 63.30; H, 4.55; N, 2.58%. Calc. for
C27H24CrNO4P, MW 509.45: C, 63.65; H, 4.75; N,
2.75%.
Complex 10b: yellow solid, m.p. 161°C (from
methylene
chloride/pentane,
mixture
of
two
diastereoisomers). IR (Nujol) cm−1: 3555, 3470 (wOH
major diast. and minor diast.), 1998 (wCO trans, both
diast.), 1896–1826 (broad, wCO cis, both diast.). 1H
NMR (300 MHz, CDCl3) l ppm: 1.85 (d, JOH–H=3.6
Hz, OH, major diast.), 1.90 (d, JOH–H=3.5 Hz, OH,
minor diast.), 3.28 (s, 3H, CH3N, major diast.), 3.45–
3.65 [m, 5H, NCH3 (minor diast.)+PhCH(OH)ꢀ
4.4. General procedure for the preparation of the
complexes 10a–g
The electrophiles (1.2 equiv.) were added at −78°C
to a tetrahydrofuran solution (10 ml) of the conjugated

242
S. Maiorana et al. / Inorganica Chimica Acta 296 (1999) 236–245
CH2ꢀCꢁCr (major diast.+minor diast.)], 3.75 (m, 1H,
Ph2PꢀCHꢀCH2ꢀN, major diast.+minor diast.), 4.10
[m, 1H, Ph2PꢀCHꢀC(H)HꢀN, major diast.+minor
diast.], 4.75 [m, 1H, Ph2PꢀCHꢀCH(H)ꢀN, major
diast.+minor diast.], 5.47 [dt, 1H, Jvic1=9.3 Hz,
73.26. Anal. Found: C, 61.55; H, 4.72; N, 4.37%. Calc.
for C34H29CrN2O7P, MW 615.59: C, 61.82; H, 4.42; N,
4.24%.
Complex 10d: yellow solid, m.p. 153°C (from
methylene chloride/pentane, mixture of two diastereo-
isomers); IR (Nujol) cm−1: 3605, (wOH, both diast.),
1995 (wCO trans, both diast.), 1896–1836 (broad, wCO
Jvic2=3.6 Hz, JH–OH=3.6 Hz, PhCHOH, major
diast.], 5.68 (m, 1H, PhCHOH, minor diast.), 6.55 (d,
2H arom, Jortho=7.2 Hz, minor diast.), 6.61 (d, 2H
arom, Jortho=7.0 Hz, major diast.), 6.90–7.60 (m, 18H
arom, major diast.+minor diast.). 13C NMR (75 MHz,
CDCl3) l ppm: 39.20 (Ph2PꢀCHꢀCH2, major diast.+
minor diast.), 45.60 (NꢀCH3, major diast.+minor
diast.), 60.09 [CrꢁCꢀCH2ꢀCH(OH)Ph, major diast.+
minor diast.], 65.43 (Ph2PꢀCHꢀCH2ꢀN, major diast.+
minor diast.), 72.82 [CrꢁCꢀCH2ꢀCH(OH)Ph major
diast.+minor diast.], 125.52, 126.39, 127.51, 127.54,
127.82, 128.18, 128.35, 128.63, 128.83, 129.89, 130.03,
130.31, 135.51, 135.83 (CH, arom, major diast.+minor
diast.), 131.72 (d, Cq, JP–C=30.4 Hz), 138.35 (Cq,
major diast.+minor diast.), 139.04 (d, Cq, JPꢀC=35.4
Hz), 144.46 (Cq, major diast.+minor diast.), 220.69,
220.81, 224.19, 224.38, 224.53, 228.98, 229.18, 229.44
(CO major diast.+minor diast.), 281.75 (CrꢁCꢀC, mi-
nor diast.), 281.94 (CrꢁCꢀC, major diast.). 31P NMR
(121 MHz, CDCl3, H3PO4 as external standard) l ppm:
78.33 (minor diast.), 75.19 (major diast.). Anal. Found:
C, 66.55; H, 5.12; N, 2.10%. Calc. for C34H30CrNO5P,
MW 615.59: C, 66.34; H, 4.91; N, 2.28%.
1
cis, both diast.). H NMR (300 MHz, CDCl3) l ppm:
1.0 [m, 3H, ꢀCH(OH)ꢀCH2CH3], 1.43 (d, 1H, JOHꢀH
=
5.1 Hz, OH, major diast.), 1.65 [m, 2H,
CH(OH)ꢀCH2CH3+OH minor diast.], 3.20 [m, 1H,
EtCH(OH)ꢀC(H)HꢀCꢁCr, major diast.+minor diast.],
3.37 (s, 3H, CH3N, major diast.), 3.45–3.65 [m, 1H,
EtCH(OH)ꢀC(H)HꢀCꢁCr
(major
diast.+minor
diast.)+s, 3H, NCH3 (minor diast.)], 3.59 (m, 1H,
Ph2PꢀCHꢀCH2ꢀN minor diast.), 3.75 (m, 1H, Ph2Pꢀ
CHꢀCH2ꢀN, major diast.), 3.90–4.15 [m, 1H,
Ph2PꢀCHꢀC(H)HꢀN, major diast.+minor diast.],
4.20–4.40 [EtCH(OH)ꢀCH2ꢀCꢁCr (major diast.+mi-
nor diast.)], 4.65–4.85 [m, 1H, Ph2PꢀCHꢀCH(H)ꢀN,
major diast.+minor diast.], 6.52 (d, 2H arom, Jortho
=
7.2 Hz, minor diast.), 6.63 (d, 2H arom, Jortho=6.5 Hz,
major diast.), 6.90–7.60 (m, 13H arom, major diast.
+minor diast.). 13C NMR (75 MHz, CDCl3) l ppm:
10.37 [(CH(OH)ꢀCH2CH3, major diast.], 10.43
[(CH(OH)ꢀCH2CH3 minor diast.], 32.00 [(CH(OH)ꢀ
CH2CH3, minor diast.], 32.11 [(CH(OH)ꢀCH2CH3, ma-
jor diast.], 39.61 (Ph2PꢀCHꢀCH2ꢀ, minor diast.), 39.72
(Ph2PꢀCHꢀCH2ꢀ, major diast.), 45.81 (NꢀCH3, minor
diast.), 46.34 (NꢀCH3, major diast.), 58.04 [CrꢁCꢀ
CH2ꢀCH(OH)ꢀCH2CH3, minor diast.], 58.39 [CrꢁCꢀ
CH2ꢀCH(OH)ꢀCH2CH3, major diast.] 65.80 (Ph2Pꢀ
CHꢀCH2ꢀN, minor diast.), 65.97 (Ph2PꢀCHꢀCH2ꢀN,
major diast.), 72.36 [CrꢁCꢀCH2ꢀCH(OH)ꢀCH2CH3,
major diast.], 72.59 [CrꢁCꢀCH2ꢀCH(OH)ꢀCH2CH3,
minor diast.], 126. 78, 126.87, 127.88, 128.00, 128.26,
128.60, 128.68, 128.79, 129.24, 130.27, 130.46, 130.70,
130.81, 130.92, 135.75, 135.91, 136.11, 136.28 (CH,
arom, both diast.), 131.61 (d, Cq, JPꢀC=30.1 Hz,
PhꢀPꢀ, minor diast.), 132.40 (d, Cq, JPꢀC=30.4 Hz,
PhꢀPꢀ, major diast.), 138.68 (d, JPꢀC=5.2 Hz, Cq, Ph,
major diast.), 139.27 (d, JPꢀC=34.6 Hz, Cq, PhꢀPꢀ,
minor diast.), 139.32 (d, JPꢀC=7.3 Hz, Cq, Ph, minor
diast.), 140.11 (d, Cq, JPꢀC=33.4 Hz, PhꢀPꢀ, major
diast.), 220.64 (d, JPꢀC=8.8 Hz, CO, minor diast.),
221.24 (d, JPꢀC=9.8 Hz, CO, major diast.), 224.76 (d,
Complex 10c: orange solid, m.p. 155°C (dec.) (from
methylene chloride/pentane, mixture of two diastereo-
isomers). Data for the major diastereoisomer: m.p.
170°C (dec.) (from methylene chloride/pentane). IR
(Nujol) cm−1: 3470 (wOH), 1991 (wCO trans), 1866–
1
1826 (broad, wCO cis). H NMR (300 MHz, CDCl3) l
ppm: 2.10 (d, JOH–H=3.5 Hz, OH), 3.34 (s, 3H,
NꢀCH3), 3.45 [dd, 1H, Jgem=12.6 Hz, Jvic=10.3 Hz,
PhCH(OH)ꢀC(H)HꢀCꢁCr], 3.65 [dd, 1H, Jgem=12.6
Hz, Jvic=3.7 Hz, PhCH(OH)ꢀCH(H)ꢀCꢁCr], 3.83 (m,
1H, Ph2PꢀCHꢀCH2ꢀN), 4.23 [ddd, 1H, JPꢀH=29 Hz,
J
gem=13.5 Hz, Jvic=1.6 Hz, Ph2PꢀCHꢀC(H)HꢀN],
4.76 [m, 1H, Ph2PꢀCHꢀCH(H)ꢀN], 5.65 [dt, 1H,
vic1=10.1 Hz, vic2=JHꢀOH=3.5 Hz, pNO2Ph-
J
J
CH(OH)ꢀCH2ꢀ], 6.65 (d, 2H arom, Jortho=6.8 Hz),
6.90–7.50 (m, 13H arom), 7.67 (bd 2H, system AA%,
J
J
ortho=8.7 Hz, pNO2Ph–), 8.25 (bd 2H, system BB%,
ortho=8.7 Hz, pNO2Ph. 13C NMR (75 MHz, CDCl3) l
ppm: 39.45 (d, JPꢀC=8 Hz Ph2PꢀCHꢀCH2), 46.20
J
PꢀC=13.3 Hz, CO, major diast.), 225.96 (d, JPꢀC=
(NꢀCH3), 59.95 [CrꢁCꢀCH2ꢀCH(OH)Ar], 66.17 (d,
13.2 Hz, CO, minor diast.), 229.66, 229.85, 229.98,
230.47 (CO, major diast.+minor diast.), 283.45 (d,
JPꢀC=13 Hz Ph2PꢀCHꢀCH2ꢀN), 72.61 [CrꢁCꢀ
CH2ꢀCH(OH)Ar], 122.73, 124.32, 126.72, 127.03,
127.99, 128.12, 128.74, 128.87, 129.40, 130.45, 130.64,
130.76, 135.65, 135.82 (CH, arom), 131.70 (d, Cq,
J
PꢀC=11.6 Hz CrꢁCꢀC, minor diast.), 283.64 (d,
CrꢁCꢀC, JPꢀC=16.3 Hz, major diast.). 31P NMR (121
MHz, CDCl3, H3PO4 as external standard) l ppm:
78.76 (minor diast.), 74.79 (major diast.). Anal. Found:
C, 63.25; H, 5.25; N, 2.36%. Calc. for C30H30CrNO5P,
MW 567.55: C, 63.49; H, 5.33; N, 2.47%.
JPꢀC=30 Hz), 138.50 (Cq), 140.04 (d, Cq, JPꢀC=35
Hz), 148.10 (Cq, Ar), 151.10 (Cq, Ar), 220.3, 224.75,
229.87, 230.05 (CO), 288.40 (Cr=CꢀC). 31P NMR (121
MHz, CDCl3, H3PO4 as external standard) l ppm:

S. Maiorana et al. / Inorganica Chimica Acta 296 (1999) 236–245
243
Complex 10e: yellow solid, m.p. 110°C (from
methylene chloride/pentane, mixture of two diastereo-
isomers); IR (Nujol) cm−1: 3601, (wOH, both diast.),
1988 (wCO trans, both diast.), 1890–1840 (broad, wCO
cis, both diast.). H NMR (300 MHz, CDCl3) l ppm:
0.94 [d, 3H, Jvic=3.6 Hz, ꢀCH(OH)ꢀCH(CH3)CH3,
2.41%. Calc, for C31H32CrNO5P, MW 581.56: C, 63.59;
H, 5.63; N, 2.34%.
Complex 10f: yellow solid, m.p. 163°C (from
methylene chloride/pentane, mixture of two diastereo-
isomers). IR (Nujol) cm−1: 1994 (wCO trans, both
diast.), 1986–1833 (broad, wCO cis, both diast.), 1554
1
1
major diast.], 0.99 [d, 3H,
(OH)ꢀCHCH3(CH3), major diast.], 1.01 [d, 3H, Jvic
J
vic=3.6 Hz, ꢀCH-
(was NO2, both diast.). H NMR (300 MHz, CDCl3) l
=
ppm: 2.7 (s, 3H, NCH3, one diast.), 2.93 (s, 3H, NCH3,
4.3 Hz, ꢀCH(OH)ꢀCHCH3(CH3), minor diast.], 1.04 [d,
3H, Jvic=4.3 Hz, ꢀCH(OH)ꢀCHCH3(CH3), minor
diast.], 1.37 (d, 1H, JOHꢀH=4.7 Hz, OH major diast.),
1.48 (d, 1H, JOHꢀH=5.1 Hz, OH diast. minor), 1.80 [m,
1H, CH(OH)ꢀCH(CH3)2], 3.20 [m, 1H, (CH3)2CH-
(OH)ꢀC(H)HꢀCꢁCr (major diast.+minor diast.)], 3.37
(s, 3H, CH3N, major diast.), 3.45–3.65 [m, 1H,
(CH3)2CH(OH)ꢀC(H)HꢀCꢁCr (major diast.+minor
diast.)+s, 3H, NCH3 (minor diast.)], 3.59 (m, 1H,
Ph2PꢀCHꢀCH2ꢀN minor diast.), 3.74 (m, 1H,
Ph2PꢀCHꢀCH2ꢀN, major diast.), 3.90–4.20 [m, 1H,
Ph2PꢀCHꢀC(H)HꢀN, major diast.+minor diast.],
one diast.), 3.20–3.30 [m, 2H, CrꢁCꢀC(H)Hꢀ
CH(Ph)ꢀCH2ꢀ, +CrꢁCꢀC(H)2CH(Ph)ꢀCH2ꢀ
both
diast.], 3.48 [m, 1H, CrꢁCꢀCH(H)ꢀCH(Ph)ꢀCH2ꢀ, one
diast.], 3.55–4.10 [m, 6H, CrꢁCꢀC(H)HꢀCH-(Ph)ꢀ
CH2ꢀ + Ph2 PꢀCHꢀC(H)HꢀN + Ph2PꢀCHꢀCH2ꢀN,
both diast.], 4.30 [m, 1H, Ph2PꢀCHꢀCH(H)ꢀN], 4.82
[m, 2H, CrꢁCꢀCH2ꢀCH(Ph)ꢀCH2ꢀNO2, one diast.],
5.02 [m, 2H, CrꢁCꢀCH2ꢀCH(Ph)ꢀCH2ꢀNO2, one
diast.], 6.48 (bd, 2H, Jortho=7.5 Hz, one diast.) 6.68
(bd, 2H arom, Jortho=7.5 Hz, one diast.), 6.90–7.40 (m,
18H arom both diast.). 13C NMR (75 MHz, CDCl3) l
ppm: 38.24 (d, JPꢀC=15.5 Hz, Ph2PꢀCHꢀCH2ꢀ, one
diast.), 38.68 (Ph2PꢀCHꢀCH2ꢀ, one diast.), 42.56
[(PhꢀCHꢀCH2NO2, both diast.), 43.32 (NꢀCH3, one
diast.)], 45.93 (NꢀCH3, one diast.), 60.24 [CrꢁCꢀ
CH2ꢀCH(Ph)ꢀCH2, both diast.], 65.43 (Ph2PꢀCHꢀ
CH2ꢀN, both diast.), 79.00 [CrꢁCꢀCH2ꢀCH(Ph)ꢀ
CH2ꢀNO2, one diast.], 79.35 [CrꢁCꢀCH2ꢀCH(Ph)ꢀ
CH2ꢀNO2, one diast.], 126.46, 126.81, 127.43, 127.64,
127.80, 128.10, 128.21, 128.43, 129.02, 129.18, 129.94,
130.21, 130.37, 134.89, 135.04, 135.63, 135.78 (CH,
arom, both diast.), 130.78 (d, Cq, JPꢀC=30.3 Hz, one
diast.), 132.06 (d, Cq, JPꢀC=30.3 Hz, one diast.), 137.01
(Cq one diast.), 138.19, 138.49, 138.67, 138.81 (Cq, both
diast.), 140.05 (d, Cq, JPꢀC=35.4 Hz, one diast.),
218.92, 220.68, 223.13, 225.09, 228.90, 228.97, 229.27,
230.12 (CO both diast.), 284.21 (d, JPꢀC=14.9 Hz
Cr=CꢀC, one diast.), 285.49 (d, CrꢁCꢀC, JPꢀC=15.1
Hz, one diast.). 31P NMR (121 MHz, CDCl3, H3PO4 as
external standard) l ppm: 68.53 (one diast.), 78.45 (one
diast.). Anal. Found: C, 63.65; H, 4.84; N, 4.04%. Calc.
for C35H31CrN2O5P, MW 658.62: C, 63.83; H, 4.74; N,
4.25%.
4.25–4.35
[(CH3)2CH(OH)ꢀCH2ꢀC=Cr
(major
diast.+minor diast.)], 4.60–4.80 [m, 1H, Ph2PꢀCHꢀ
CH(H)ꢀN, major diast.+minor diast.], 6.53 (d, 2H
arom, Jortho=7.2 Hz, minor diast.), 6.62 (d, 2H arom,
J
ortho=6.7 Hz, major diast.), 6.90–7.60 (m, 13H arom,
major diast.+minor diast.). 13C NMR (75 MHz,
CDCl3) ppm: 17.71, 18.98, 19.25 [(CH(OH)ꢀ
l
CH(CH3)2, major diast.+minor diast.], 35.50
[(CH(OH)ꢀCH(CH3)2, major diast.], 35.55 [(CH(OH)ꢀ
CH(CH3)2, minor diast.] 39.70 (Ph2PꢀCHꢀCH2ꢀ, minor
diast.), 39.78 (Ph2PꢀCHꢀCH2ꢀ, major diast.), 45.78
(NꢀCH3, major diast.), 46.25 (NꢀCH3, minor diast.),
55.17 [CrꢁCꢀCH2ꢀCH(OH)ꢀCH(CH3)2, minor diast.],
55.69 [CrꢁCꢀCH2ꢀCH(OH)ꢀCH(CH3)2, major diast.]
65.76 (Ph2PꢀCHꢀCH2ꢀN, minor diast.), 65.94
(Ph2PꢀCHꢀCH2ꢀN, major diast.), 75.40 [CrꢁCꢀCH2ꢀ
CH(OH)ꢀCH(CH3)2, minor diast.], 75.55 [CrꢁCꢀCH2ꢀ
CH(OH)ꢀCH(CH3)2, major diast.], 126. 75, 126.82,
127.83, 127.96, 128.25, 128.57, 128.65, 128.77, 129.23,
130.25, 130.44, 130.73, 130.79, 130.84, 130.91, 135.77,
135.93, 136.11, 136.28 (CH, arom, both diast.), 131.68
(d, Cq, JPꢀC=29.8 Hz, PhꢀPꢀ, major diast.), 132.38 (d,
Cq, JPꢀC=30.3 Hz, PhꢀPꢀ, minor diast.), 138.77 (d,
Complex 10g: yellow solid, m.p. 124°C (from
methylene
chloride/pentane,
mixture
of
two
JPꢀC=5.1 Hz, Cq, Ph, minor diast), 139.29 (d, JPꢀC
=
diastereoisomers). IR (Nujol) cm−1: 1991 (wCO trans,
both diast.), 1986–1833 (broad, wCO cis, both diast.),
35.1 Hz, Cq, PhꢀPꢀ, major diast.), 139.37 (d, JPꢀC=7.2
Hz, Cq, Ph, minor diast.) 140.08 (d, Cq, JPꢀC=33.7 Hz,
PhꢀPꢀ, major diast.), 220.72 (d, JPꢀC=8.5 Hz, CO,
major diast.), 221.34 (d, JPꢀC=9.8 Hz, CO, minor
diast.), 224.80 (d, JPꢀC=13.2 Hz, CO, minor diast.),
226.04 (d, JPꢀC=13.4 Hz, CO, major diast.), 229.54,
229.76, 229.92 (CO, major diast.+minor diast.), 230.46
(CO, major diast.), 283.95 (d, JPꢀC=14.0 Hz CrꢁCꢀC,
major diast.), 284.14 (d, CrꢁCꢀC, JPꢀC=14.8 Hz, mi-
nor diast.). 31P NMR (121 MHz, CDCl3, H3PO4 as
external standard) l ppm: 78.71 (minor diast.), 75.18
(major diast.). Anal. Found: C, 64.02; H, 5.55; N,
1
1709 (wCꢁO, both diast.). H NMR (300 MHz, CDCl3)
l ppm: 1.60–2.50 (m, 7H, cyclohexyl, major diast.+
minor diast.), 3.10 [dd, 1H, Jgem=13.0 Hz, Jvic=5.3
Hz, CrꢁCꢀC(H)Hꢀcyclohexyl], 3.27 (s, 3H, NCH3, mi-
nor diast.), 3.30 (s, 3H, NCH3, major diast.), 3.32–3.80
[m, 2H, CrꢁCꢀC(H)Hꢀcyclohexyl+Ph2PꢀCHꢀCH2ꢀN,
minor diast.+major diast.], 4.05 [m, 1H, Ph2PꢀCHꢀ
C(H)HꢀN], 4.66 [m, 1H, Ph2PꢀCHꢀC(H)HꢀN, minor
diast.+major diast.], 4.78 [m, 1H, Ph2PꢀCHꢀ
CH(H)ꢀN, minor diast.+major diast.], 6.56 (d, 2H
arom, Jortho=7.3 Hz, major diast.), 6.61 (d, 2H arom,

244
S. Maiorana et al. / Inorganica Chimica Acta 296 (1999) 236–245
Table 3
major diast.), 211.09 (CH2ꢀCꢁO, both diast.), 215.83
(CO both diast.), 220.09 (d, JPꢀC=9.5 Hz, CO, major
diast.), 220.23 (d, JPꢀC=12.0 Hz, CO, minor diast.),
224.73 (d, JPꢀC=13.6 Hz, CO, minor diast.), 225.07 (d,
Crystal data and structure refinement for 10c·0.75CH2Cl2
Formula
Formula weight
Temperature (K)
Wavelength (A)
Crystal system
Space group
C34H29CrN2O7P·0.75CH2Cl2
724.26
293(2)
0.71073
triclinic
JPꢀC=13.3 Hz, CO, major diast.), 229.92 (CO, major
,
diast.), 230.10 (CO, minor diast.), 288.71 (d, JPꢀC=16.0
Hz CrꢁCꢀC, minor diast.), 288.92 (d, CrꢁCꢀC, JPꢀC
=
(
P1
15.4 Hz, major diast.). 31P NMR (121 MHz, CDCl3,
H3PO4 as external standard) l ppm: 75.31 (minor
diast.), 76.88 (major diast.). Anal. Found: C, 64.88; H,
5.48; N, 2.20%. Calc. for C33H32CrNO5P, MW 605.58:
C, 65.45; H, 5.33; N, 2.31%.
Unit cell dimensions
,
a (A)
18.255(6)
11.792(5)
8.533(4)
68.22(3)
81.66(4)
81.51(4)
1678.9(12)
2
,
b (A)
,
c (A)
h (°)
i (°)
k (°)
3
4.5. Crystal structure determination of the complex
10c·0.75CH2Cl2.
,
Volume (A )
Z
Density (calc., Mg m−3
)
1.433
0.559
747
Absorption coefficient, (v, mm−1
F(000)
)
The intensity data of 10c·0.75CH2Cl2 were collected
at room temperature (22°C) on a Siemens AED single-
crystal diffractometer using the graphite-monochro-
mated Mo Ka radiation and the q–2q scan technique.
Final unit cell parameters were obtained from a least-
squares refinement using 24 reflections. Crystallo-
graphic and experimental details are summarized in
Table 3.
Data were corrected for Lorentz and polarization
effects in the usual manner. A correction for absorption
was made for both complexes (maximum and minimum
value for the transmission coefficient was 1.000 and
0.6873 [18]).
Crystal size
q range (°)
Index ranges
0.21×0.34×0.35 mm
3.08–25.00
−215h521, −125k514,
05l510
5893
5893
Reflections collected
Independent reflections
Observed reflections [I\2|(I)]
Refinement method
3167
Based on F2
5893/0/290
Data/restraint/parameters
Flack index
−0.09(4)
0.769
R1=0.0769, wR2=0.2087
R1=0.1652, wR2=0.2405
Goodness-of-fit on F2
Final R indices [I\2s(I)] a
R indices (all data)
Largest difference peak and hole 0.740 and −0.429
−3
,
(e A
)
The structure was solved by Patterson and Fourier
methods and refined by full-matrix least-squares proce-
a R1=S ꢀFo−Fcꢀ/ꢀS(Fo); wR2=[S [w(Fo2−Fc2)2]/S [w(Fo2)2]]1/2
.
2
dures (based on Fo ) with anisotropic thermal parame-
ters in the last cicles of refinement for the Cr, P, N, O
and C1ꢀC4 atoms only. Molecules of the dichloro-
methane solvent are also present in the crystals. These
have been found disordered and distributed around the
inversion center in three positions, two of which having
the carbon atom in common. The hydrogen atoms
(excepting those of the disordered solvent molecules)
were introduced into the geometrically calculated posi-
tions and refined riding on the atoms to which they are
attached. In the final cycles of refinement a weighting
scheme w=1/[|2Fo2+ (0.1603 P)2] (10c·0.75CH2Cl2),
J
ortho=7.8 Hz, minor diast.), 6.90–7.40 (m, 13H arom).
13C NMR (75 MHz, CDCl3) l ppm: 25.84 (OꢁCꢀ
CH2ꢀCH2ꢀCH2ꢀ, minor diast.), 25.99 (OꢁCꢀCH2ꢀ
CH2ꢀCH2ꢀ, major diast.), 31.95 (OꢁCꢀCH2ꢀCH2ꢀ
CH2ꢀ, major diast.), 32.22 (OꢁCꢀCH2ꢀCH2ꢀCH2ꢀ, mi-
nor diast.) 38.62 (Ph2PꢀCHꢀCH2ꢀ, minor diast.), 38.76
(Ph2PꢀCHꢀCH2ꢀ, major diast.), 39.20 (bs, OꢁCꢀCH2ꢀ
CHꢀCH2ꢀ, both diast.), 41.61 (OꢁCꢀCH2ꢀCH2ꢀCH2ꢀ,
minor diast.), 41.72 (OꢁCꢀCH2ꢀCH2ꢀCH2ꢀ, major
diast.), 43.32 (NꢀCH3, one diast.), 44.79 (NꢀCH3, ma-
jor diast.), 45.05 (NꢀCH3, minor diast.), 48.32
(OꢁCꢀCH2ꢀCHꢀCH2, minor diast.), 48.54 (OꢁCꢀCH2ꢀ
CHꢀCH2, major diast.), 58.63 [bs, CrꢁCꢀCH2ꢀ
CHꢀCH2ꢀCꢁO, both diast.], 65.53 (Ph2PꢀCHꢀCH2ꢀN,
minor diast.), 65.72 (Ph2PꢀCHꢀCH2ꢀN, major diast.),
126.90, 127.88, 128.00, 128.37, 128.53, 128.68, 128.77,
128.88, 130.40, 130.57, 130.70, 135.80, 135.89, 135.97,
2
where P=(Fo2+2Fc )/3 was used.
All calculations were carried out on the CNRDIF
computers of the ‘Centro di Studio per la Strutturistica
Diffrattometrica’ del CNR, Parma, using the SHELXL-97
system of crystallographic computer programs [19].
136.04 (CH, arom, both diast.), 131.87 (d, Cq, JPꢀC
30.7 Hz, PhꢀPꢀ, major diast.), 132.03 (d, Cq, JPꢀC
30.8 Hz, PhꢀPꢀ, minor diast.), 138.58 (d, JPꢀC=6.1 Hz,
Cq, Ph, minor diast.), 138.58 (d, JPꢀC=5.4 Hz, Cq, Ph,
major diast.), 139.48 (d, JPꢀC=34.8 Hz, Cq, PhꢀPꢀ,
major diast.), 139.78 (d, Cq, JPꢀC=34.0 Hz, PhꢀPꢀ,
=
=
5. Supplementary material
The supplementary material for the structure includes
the lists of atomic coordinates for the non-H atoms, of
calculated coordinates for the hydrogen atoms, of an-
isotropic thermal parameters. The details of the crystal

S. Maiorana et al. / Inorganica Chimica Acta 296 (1999) 236–245
245
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structure investigation are deposited to the Cambridge
Crystallographic Data Center as supplementary publi-
cations (copies of the data can be obtained free of
charge on application to CCDC, 12 Union Road, Cam-
bridge CB2 1EZ, UK (fax: +44-1223-336 033; e-mail:
deposit@ccdc.cam.ac.uk.
Acknowledgements
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[10] U. Schick, L. Jordi, S. Ricard, J. Veciana, K.H. Do¨tz, J.M.
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We thank the Ministero dell’Universita` e della
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