New synthesis of phosphine oxides bearing a 2-methyl-4-oxopent-2-yl substituent

Article abstract of DOI:10.1016/j.mencom.2010.03.007

A new approach to the synthesis of substituted phosphine oxides bearing an oxo group at the γ-position to the phosphorus atom was developed.

Full text of DOI:10.1016/j.mencom.2010.03.007

Mendeleev
Communications
Mendeleev Commun., 2010, 20, 86–88
New synthesis of phosphine oxides bearing
a 2-methyl-4-oxopent-2-yl substituent
Dmitry A. Tatarinov,a,b Vladimir F. Mironov,*a,b Tamara A. Baronova,a
Anton A. Kostin,a,b Dmitry B. Krivolapov,a Boris I. Buzykina and Igor A. Litvinova
a A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Scientific Centre of the Russian Academy of
Sciences, 420088 Kazan, Russian Federation. Fax: +7 843 273 1872; e-mail: mironov@iopc.kcn.ru
b A. M. Butlerov Chemical Institute, Kazan State University, 420008 Kazan, Russian Federation.
Fax: +7 843 231 5416
DOI: 10.1016/j.mencom.2010.03.007
A new approach to the synthesis of substituted phosphine oxides bearing an oxo group at the γ-position to the phosphorus atom
was developed.
A current trend in modern organic chemistry is the design of
new phosphorus-containing ligands, which possess high stability
and selectivity for complexations. Phosphine oxides are the
most convenient precursors in the phosphine synthesis. Owing
to a high chemical stability in acid and alkaline media and
pronounced complexing properties with respect to the metal
ions, phosphine oxides are used as ligands in metallocomplex
catalysis1–4 and bifunctional one,5,6 for the creation of ion-
selective electrodes7,8 and extraction of metals.9,10 Fluorescent
complexes of phosphine oxides with rare-earth metals are the
most suitable for the creation of OLEDs11,12 due to a high light-
emitting ability and stability.
trum of phosphine oxide 2a. The first step of decomposition
leads to the elimination of the methyl or ethyl group bonded
with phosphorus atom and causes the appearance of peaks with
m/z 189 and 175 in the mass spectrum. The directions of the
fragmentation involving the removal of an acetyl group and an
acetone fragment are characteristic of the obtained phosphine
†
Melting points (uncorrected) were measured with a Boetius melting
point apparatus. NMR spectra were recorded on Bruker Avance-600 (1H,
600 MHz; 13C, 150.9 MHz), Bruker Avance-400 (1H, 400 MHz; 13C,
100.6 MHz) and Bruker CXP-100 (31P, 36.48 MHz) spectrometers. The
d
H and dP values were determined relative to internal (HMDS) or external
(H3PO4) standards. The IR spectrum was recorded on a Bruker Vector-22
instrument in Nujol. EI mass spectra were obtained on a TRACE MS
Finnigan MAT instrument; the ionization energy was 70 eV and the ion
source temperature was 200 °C. The samples were introduced into the
ion source via a direct inlet system. The evaporating ampoule was heated
from 35 to 150 °C at a rate of 35 K min–1. The mass spectrometric data
were processed using the Xcalibur system program.
Diethyl(2-methyl-4-oxopent-2-yl)phosphine oxide 2a. Compound 1
(5.7 g, 0.0316 mol) was added dropwise with stirring to the ethylmag-
nesium bromide prepared from magnesium (1.9 g, 0.079 mol) and ethyl
bromide (5.9 ml, 8.6 g, 0.079 mol) in diethyl ether (30 ml) according to
the standard procedure in the argon atmosphere. The reaction mixture was
refluxed during 1 h, cooled to 20 °C and treated with water (30 ml) and
then concentrated hydrochloric acid (7 ml). Water and organic layers were
separated and the water layer was extracted three times with CH2Cl2.
Combined methylene chloride extract and organic layer were evaporated
and then dried in a vacuum (12 Torr, 100 °C) to give compound 2a, a
light-yellow oil, 5.6 g (86% yield), bp 100–102 °C (0.02 Torr), nD20 1.4831,
d420 1.038. Found (%): C, 58.60; H, 10.56; P, 15.36. Calc. for C10H21O2P
(%): C, 58.80; H, 10.36; P, 15.16.
Chiral phosphine oxides, as well as chiral phosphines, attract
considerable attention due to their application as ligands for
complex catalysts in asymmetric synthesis13–15 and in other
fields.16
Here, we propose a new approach to the synthesis of func-
tionally substituted phosphine oxides, which contain an oxo
group at the γ-position to the phosphorus atom. This approach
involves the reaction of such easily available heterocycles as
1,2-oxaphospholene-2-oxides with organometallic compounds
and results in a formation of the new P–C bond. Thus, the
reaction of well-known 2-chloro-3,3,5-trimethyl-1,2-oxaphos-
pholene-2-oxide 117–19 with organomagnesium compounds in
a ratio of 1:2 (Scheme 1) gives rise to the substitution of both
exocyclic P–Cl and endocyclic P–O bonds. A cleavage of
the cycle and a formation of dialkyl(2-methyl-4-oxopent-2-yl)-
phosphine oxides 2 with high yields (> 90%) occur in this
process.†
The structure and composition of isolated phosphine oxides
2 were established by NMR spectroscopy and high-resolution
Dihexyl(2-methyl-4-oxopent-2-yl)phosphine oxide 2b was prepared as
described above from magnesium (9.16 g, 0.382 mol), 1-iodohexane
(56.6 ml, 80.98 g, 0.382 mol) in diethyl ether (80 ml) and 1,2-oxaphos-
pholene oxide 1 (30 g, 0.166 mol). Yield of 2b, 47 g (90%), transparent
oil, bp 160–162 °C (0.06 Torr), nD20 1.4695. 1H NMR (600 MHz, CDCl3)
d: 0.88 (br. t, 6H, H12, 3JHCCH 7.1 Hz), 1.25 (d, 6H, H1, H6, 3JPCCH 14.8 Hz),
mass spectrometry. There is a peak of the protonated molecular
+
·
ion with m/z 205 [M + H] in the electron impact mass spec-
i, 2RMgX
O
O
O
3
1.27 (m, 8H, H10, H11), 1.36 (m, 4H, H9, JHCCH 6.2–6.5 Hz), 1.56 (m,
ii, H2O, H+
– MgClX
R
R
3
P
O
P
2
4H, H8, two AB-parts of two ABCD-spectra), 1.63 and 1.71 (2m, 4H,
PCH7, two CD-parts of two ABCD-spectra), 2.14 (s, 3H, H5), 2.65 (d,
2H, H3, 3JPCCH 8.0 Hz). 31P-{1H} NMR (36.46 MHz, CDCl3) dP: 51.6 (s).
4
Cl
1
6
5
1
2a,b
+
+
·
·
MS, m/z: 317 [M + H] , 316 [M] , 287 [M – Et], 273 [M – C2H3O],
279 [M – C3H5O], 235 [M – C6H9], 231 [M – C6H13], 218 [C12H27OP],
217 [C12H26OP], 162 [C12H26OP – C4H7], 161 [C6H14OP – C4H8], 148
[M – C6H11 – C5H10], 133 [C6H14OP], 99.0 [C6H11O], 78, 55, 43, 29.
Found (%): C, 68.22; H, 11.88; P, 9.89. Calc. for C18H37O2P (%): C, 68.32;
H, 11.78; P, 9.79.
7
8
a R = CH2Me
7
8
9
10
11
12
b R = CH2CH2CH2CH2CH2Me
Scheme 1
– 86 –
© 2010 Mendeleev Communications. All rights reserved.

Mendeleev Commun., 2010, 20, 86–88
oxides and result in the appearance of peaks with m/z 161 and
147. An origination of other characteristic ions is caused by the
subsequent decomposition of the above ions.
We have found that the utilization of such heterocycles as
2-alkyl-3,3,5-trimethyl-1,2-oxaphospholene-2-oxide 317,18,20,21
bearing two exo- and endocyclic P–C bonds in the reaction with
the organomagnesium compounds allows us to synthesize asym-
metrically substituted phosphine oxides 4, in which there are
three different substituents at the phosphorus atom.‡
i, R2MgX
ii, HCl, H2O
O
O
R1
R2
O
3
P
O
P
2
– MgClX
R1
4
1
6
5
3a,b
4a,b
7
8
9
10
11
a R1 = Me, R2 = CH2CH2CH2Me
7
8
b R1 = CH2Me, R2 = 2-MeOC6H4
Thus, the reaction of oxaphospholenes 3 with Grignard
reagents followed by hydrolysis resulted in the formation of
2-methyl-4-oxopent-2-ylphosphine oxides 4 with the yields
of > 95%. Namely, the use of heterocycles such as 3 allows
us to exclude the formation of by-products and supplies high
Scheme 2
reaction selectivity and the purity and high yield of phosphine
oxides 4.
The structures of the compounds obtained were confirmed
by H, 13C, 31P NMR, IR spectroscopy and mass spectrometry.
‡
1
Butyl(2-methyl-4-oxopent-2-yl)methylphosphine oxide 4a was prepared
The protons of methyl groups (C1H3, C6H3) are nonequivalent
as described above from magnesium (1.1 g, 0.046 mol), 1-bromobutane
(4.9 ml, 6.3 g, 0.046 mol) and 2,3,3,5-tetramethyl-1,2-oxaphosphol-4-ene-
2-oxide 3a (5.5 g, 0.0344 mol) in diethyl ether (60 ml). Yield of 4a,
7.2 g (96%), a brown oil. 1H NMR (600 MHz, CDCl3) d: 0.44 (t, 3H,
H11, 3JHCCH 7.3 Hz), 0.79 [d, 6H, H1 (+ H6), 3JPCCH 15.3 Hz], 0.80 [d, 6H,
1
in the H NMR spectrum of phosphine oxides 4 (d 1.22 ppm,
3
3JPCCH 15.9 Hz; d 1.54 ppm, JPCCH 11.4 Hz) that is caused by
the presence of the asymmetric phosphorus atom. The protons
of R1 and R2 substituents resonate as AB-part of the ABMX3
system. The protons of the C3H2 group are also nonequivalent
and are revealed in view of the AB-multiplet.
3
2
H6 (+ H1), JPCCH 15.3 Hz], 0.93 [d, 5H, H7 (+ H10), JPCH 11.7 Hz],
0.97 [m, 5H, H10 (+ H7), JHCCH 7.3–7.4 Hz, JHCCH 7.3–7.4 Hz], 1.04,
3
3
1.13, 1.21, 1.29 (4m, 4H, H8,9), 1.68 (s, 3H, H5), 2.19–2.21 (m, 2H, H3,
AB-spectrum, JPCCH 8.8 Hz). 13C NMR (150.9 MHz, CDCl3) d: 19.72
3
The resonance picture of the 2-methyl-4-oxopentyl substi-
tuent in 13C NMR spectra has a similar character for all of the
obtained compounds. A characteristic doublet (3JPCCC 10–12 Hz)
of carbonyl group is observed at the low-field region. The sig-
nals of the sp3 carbons are revealed in a high-field region. The
doublets of C2 and C3 are the most easily interpreted due to
the spin–spin coupling constants with phosphorus. Methyl groups
C1H3 and C6H3 of phosphine oxides 4a,b are nonequivalent
[qm (s), C1, 1JHC1 128.0 Hz], 33.49 [br. dm (d), C2, 1JPC2 66.8 Hz], 45.79
[br. t (s), C3, JHC3 125.4 Hz], 205.35 [m (d), C4, JPCCC4 12.3 Hz,
1
3
2JHCC4 5.6–5.7 Hz, 2JHCC4 5.6–5.7 Hz], 31.22 [q (s), C5, 1JHC5 127.4 Hz],
19.62 [qm (s), C6, JHC6 128.0 Hz], 8.20 [qd (d), C7, JHC7 128.9 Hz,
1
1
1JPC7 63.0 Hz], 23.64 [br. tdm (d), C8, JPC8 63.9 Hz, JHC8 125.2 Hz],
1
1
22.70 [tdm (d), C9, JHC9 125.0–127.0 Hz], 23.20 [tdm (d), C10, JHC10
1
1
125.0–127.0 Hz, 3JPCCC10 13.6 Hz], 12.58 [qm (d), C11, 1JHC11 125.0 Hz,
2JHCC11 3.7–3.9 Hz, JHCCC11 3.7–3.9 Hz]. 31P-{1H} NMR (36.46 MHz,
3
1
in 13C-{1H} NMR as well as H NMR spectra. There are no
+
·
CDCl3) dP: 54.7 (s). MS, m/z: 219 [M + H] , 203 [M – Me], 175 [M –
spectral evidences of the keto-enol tautomerism in compounds
2, 4. Moreover, the structure of phosphine oxide 4b was con-
firmed by the single-crystal X-ray diffraction (Figure 1).§ The
phosphorus atom has a distorted tetrahedral configuration.
We have investigated chemical properties of compounds 2.
Oximes 5 were obtained by treatment of phosphine oxides 2
with hydroxylamine (Scheme 3).¶
– MeCO], 161 [M – C3H5O], 145 [C6H10O2P], 119 [C5H12PO], 99 [C6H11O],
77.8, 66.9, 42.8, 18. Found (%): C, 60.43; H, 10.72; P, 14.39. Calc. for
C11H23O2P (%): C, 60.53; H, 10.62; P, 14.19.
Ethyl(2-methyl-4-oxopent-2-yl)-2-methoxyphenylphosphine oxide 4b
was prepared as described above from magnesium (2.0 g, 0.0833 mol),
1-bromo-2-methoxybenzene (10.4 ml, 15.67 g, 0.0833 mol) and 2-ethyl-
3,3,5-tetramethyl-1,2-oxaphosphol-4-ene-2-oxide 3b (6.0 g, 0.0345 mol) in
diethyl ether (70 ml). Water and organic layers were separated. Phosphine
oxide 4b was crystallized from organic layer as white precipitate. Yield of
O
R
1
4b, 9.2 g (95%), mp 97–98 °C. H NMR (600 MHz, CDCl3) d: 1.04 (dt,
i, NaOH
P
3H, H8, 3JPCCH 12.0 Hz, 3JHCCH 7.8 Hz), 1.17 (d, 3H, H1, 3JPCCH 15.9 Hz),
ii, NH2OH·HCl, EtOH
R
2a,b
3
1.34 (d, 3H, H6, JPCCH 15.4 Hz), 2.03 (m, 1H, H7, A-part of ABM3X-
– NaCl
N
spectrum, 2JPCH 14.5–15.0 Hz, 2JHH 14.5–15.0 Hz, 3JHCCH 7.6 Hz), 2.12
(s, 3H, H5), 2.32 (m, H7, 1H, B-part of ABM3X-spectrum, 3JHCCH 7.6 Hz,
HO
5a,b
a R = Et
b R = n-hexyl
2
2JPCH 7.6 Hz, JHH 14.4–15.0 Hz), 2.48 (dd, 1H, H3, A-part of ABX-
2
3
spectrum, JHH 15.9 Hz, JPCCC 9.8 Hz), 2.79 (dd, 1H, H3, B-part of
ABX-spectrum, 2JHH 15.9 Hz, 3JPCCC 7.8 Hz), 3.84 (s, 3H, H15), 6.92 (dd,
1H, H11, 4JPCCCH 5.1 Hz, 3JHCCH 8.1 Hz), 7.12 (dd, 1H, H13, 3JHCCH 7.8 Hz,
Scheme 3
3
3
§
3JHCCH 7.3 Hz), 7.51 (br. dd, 1H, H12, JHCCH 8.1 Hz, JHCCH 7.3 Hz),
7.98 (ddd, 1H, H14, 3JPCCH 12.0 Hz, 3JHCCH 7.8 Hz, 4JHCCCH 1.4–1.7 Hz).
13C NMR (150.9 MHz, CDCl3) d: 20.56 [br. qm (s), C1, 1JHC1 128.0 Hz,
The X-ray diffraction data for compound 4b were collected on an Enraf-
Nonius CAD4 automatic diffractometer using graphite monochromated
MoKα (0.71073 Å) radiation. Crystals of compound 4b (C15H23O3P) are
monoclinic, a = 12.159(6), b = 8.185(4) and c = 16.442(6) Å, b = 108.55(3)°,
V = 1551.3(12) Å3, Z = 4, dcalc = 1.209 g cm–3, space group P21/c. Cell
parameters and intensities of 3138 independent reflections, from which
2544 with I ³ 2s, were measured in the w/2q-scan, q £ 26.28° mode.
Absorption correction was not applied [m(Mo) = 1.79 cm–1]. The struc-
ture was solved by a direct method using the SIR22 program and refined
by the full matrix least-squares using the SHELXL97 program.23 All non-
hydrogen atoms were refined anisotropically. The hydrogen atoms were
calculated and refined as riding atoms. All calculations were performed
on PC using WinGX program.24 The final residuals were Robs = 0.0425,
Rw obs = 0.1185. Cell parameters, data collection and data reduction were
performed on an Alpha Station 200 computer using the MolEN program.25
All figures were made using the PLATON program.26
1
2
3JHCCC1 2.8 Hz], 35.76 [dm (d), C2, JPC2 67.9 Hz, JHCC2 3.8 Hz], 47.26
[br. t (s), C3, JHC3 126.1 Hz], 206.22 [m (d), C4, JPCCC4 11.6–12.0 Hz,
1
3
2JH3CC4 5.7–6.0 Hz, 2JH2CC4 5.7–6.0 Hz], 31.57 [q (s), C5, 1JHC5 127.2 Hz],
21.15 [br. qm (s), C6, 1JHC6 128.0 Hz, 3J
2.8 Hz], 17.25 [tdq (d), C7,
HCCC6
1JHC7 126.8 Hz, JPC7 66.1 Hz, JHC8C7 4.0–4.1 Hz], 5.13 [qdt (d), C8,
1
2
1JHC8 129.0 Hz, JPCC8 5.7 Hz, JHCC8 5.0–5.2 Hz], 116.86 [dm (d), C9,
2
2
1JPC9 82.6 Hz], 158.70 [m (d), C10, 2JPCC10 4.7 Hz], 109.95 [ddd (d), C11,
1JHC11 159.2 Hz, JPCCC11 6.5 Hz, JHC13
6.9–7.2 Hz], 133.09 [dd (s),
3
3
CC11
C12, 1JHC12 160.0 Hz, 3JHC14
8.9 Hz], 120.35 [ddd (d), C13, 1JHC13 163.0 Hz,
CC12
3JPCCC13 9.7 Hz, JHC11
7.3–7.5 Hz], 135.72 [dddd (d), C14, JHC14
3
1
CC13
163.4 Hz, 3JHC12
8.4 Hz, 2JPCC14 4.0 Hz, 2JHC13C14 4.0 Hz]. 31P-{1H} NMR
CC14
+
+
·
(36.46 MHz, CDCl3) dP: 55.3 (s). MS, m/z: 282 [M] , 267 [M – Me] , 253
[M – Et]+, 254 [M – C2H4]+, 266 [M – MeCOCH], 201 [M – MeCCH2Me2],
184 [EtP(O)-(H)C6H4OMe] [M – C6H10O] [M1], 155 [M1 – Et], 137 [M1 –
– MeOH – Me], 125 [M1 – C2H4 – MeO], 107 [M1 – EtPOH], 77 [Ph], 98
[C6H10O], 83 [C6H10O – Me]. Found (%): C, 63.80; H, 8.23; P, 10.99.
Calc. for C15H23O3P (%): C, 63.82; H, 8.21; P, 10.97.
CCDC 746980 contains the supplementary crystallographic data for this
paper. These data can be obtained free of charge from The Cambridge
Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
For details, see ‘Notice to Authors’, Mendeleev Commun., Issue 1, 2010.
– 87 –

Mendeleev Commun., 2010, 20, 86–88
of about 1:3 were observed in 31P NMR spectra. The most
C(15)
signals were duplicated in 1H NMR spectra and the integral
signal strengths were also 1:3 due to the E,Z-isomerism relative
to C=N bonds. As a whole, the spectral parameters of oximes
5a,b are similar to those for the initial phosphine oxides 2a,b.
In conclusion, a new effective synthetic approach to 2-methyl-
4-oxopent-2-ylphosphine oxides, based on the reaction of 1,2-oxa-
phospholene derivatives with the Grignard reagents, has been
developed.
C(6)
C(1)
C(3)
C(11)
C(10)
C(14)
C(2)
O(10)
C(9)
C(12)
C(4)
O(4)
P(1)
C(5)
C(7)
C(13)
O(1)
C(8)
The work was supported by the Russian Foundation for
Basic Research and Tatarstan Academy of Sciences (grant
no. 09-03-97007-r_a).
Figure 1 Molecular geometry of compound 4b in a crystal. Selected bond
lengths (Å), bond and torsion angles (°): P(1)–O(1) 1.493(2), P(1)–C(2)
1.862(2), P(1)–C(7) 1.825(2), P(1)–C(9) 1.813(2), O(4)–C(4) 1.208(3),
O(10)–C(10) 1.368(2), O(10)–C(15) 1.416(3), C(4)–C(5) 1.511(4), C(3)–
C(4) 1.492(3), C(2)–C(3) 1.548(3); O(1)–P(1)–C(2) 110.84(8), O(1)–P(1)–
C(9) 108.30(8), O(1)–P(1)–C(7) 113.19(8), C(2)–P(1)–C(9) 109.43(8),
C(2)–P(1)–C(7) 110.07(8), C(7)–P(1)–C(9) 104.77(9), C(3)–C(4)–C(5)
116.0(2), C(2)–C(3)–C(4) 119.5(2), P(1)–C(2)–C(3) 107.9(1), O(1)–P(1)–
C(2)–C(3) 21.2(2), O(1)–P(1)–C(2)–C(1) 144.3(1), O(1)–P(1)–C(2)–C(6)
–94.4(1), C(9)–P(1)–C(2)–C(3) 140.6(1), C(5)–P(1)–C(4)–C(14) –96.4(2),
O(1)–P(1)–C(9)–C(10) –175.6(2), O(1)–P(1)–C(9)–C(14) –0.7(2), C(15)–
O(6)–C(6)–C(10) 171.2(2), O(1)–P(1)–C(7)–C(8) 60.0(2).
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sodium hydroxide (0.3824 g, 0.01435 mol) in ethanol (10 ml) was added
dropwise under stirring to the cold (ice-bath) mixture of compound 2b
(2 g, 0.00844 mol) and hydroxylamine hydrochloride (0.9972 g, 0.01435 mol)
in ethanol (10 ml). The reaction mixture was refluxed during 1 h, then
the solvent was evaporated to dryness in a vacuum (12 Torr, 60 °C). The
residue was twice extracted with methylene chloride. The extract was
separated from a water layer and dried in a vacuum (12 Torr, 60 °C) to
give a light-yellow oil, which gradually formed crystals. Oxime 5b,
1.9 g (89%), was obtained as the mixture of light-yellow crystals (the
mixture of E- and Z-forms in a ratio of 1:3), mp 66–67 °C. 1H NMR
3
(400 MHz, CDCl3) d: 0.88 (t, H12, E + Z, JHCCH 7.0 Hz), 1.17 (d, H1,
H6, Z, 3JPCCH 14.7 Hz), 1.21 (d, H1, H6, E, 3JPCCH 14.6 Hz), 1.29 (m, H10,
H11, E + Z), 1.38 (m, H9, E + Z), 1.55–1.75 (m, H7, H8, E + Z), 2.11 (s,
H5, E + Z), 2.43 (d, H3, Z, 3JPCCH 7.5 Hz), 2.59 (d, H3, E, 3JPCCH 7.8 Hz).
13C NMR (100.6 MHz, CDCl3) d: 21.38 [br. qm (br. s), C1, C6, Z + E,
3
3
1JHC 127.7 Hz, JHCCC 4.9 Hz, JHC3CC 4.9 Hz], 36.11 [dm (d), C2, Z,
1JPC2 64.0 Hz], 36.09 [dm (d), C2, E, JPC2 64.0 Hz], 40.75 [tm (d), C3,
1
Z, JHC3 128.0 Hz, JPCC3 1.0 Hz], 36.09 [tm (d), C3, E, JHC3 128.0 Hz,
1
2
1
2JPCC3 2.2 Hz], 153.85 [m (d), C4, Z, JPCCC4 13.5 Hz, JHC3C4 6.6 Hz,
3
2
2JHC5C4 6.6 Hz], 153.49 [m (d), C4, E, 3J
11.8 Hz, 2J
1
6.6–6.7 Hz,
HC3C4
23 G. M. Sheldrick, SHELXL-97. Program for Crystal Structure Refinement,
PCCC4
2JHC5C4 6.6–6.7 Hz], 30.84 [qt (br. s), C5, Z, JHC5 127.1 Hz, JHC3CC5
3
University of Göttingen, Germany, 1997.
3.8 Hz], 23.26 [qm (d), C5, E, JHC5 127.2 Hz, JHC3CC5 3.8–4.0 Hz,
4JPCCCC5 0.6 Hz], 24.55 [dm (d), C7, Z, 1JPC7 60.9 Hz], 24.47 [dm (d), C7,
E, 1JPC7 60.9 Hz], 31.33 [tm (d), C8, E + Z, 1JHC8 126.0 Hz, 2JPCC8 6.3 Hz],
31.27 [tm (d), C9, E + Z, 1JHC9 126.0 Hz, 3JPCCC9 18.6 Hz], 22.47 [tm (s),
1
3
24 L. J. Farrugia, J. Appl. Crystallogr., 1999, 32, 837.
25 L. H. Straver and A. J. Schierbeek, MolEN. Structure Determination
System, Nonius B.V., Delft, The Netherlands, 1994, vols. 1 and 2.
26 A. L. Spek, Acta Crystallogr., Sect. A, 1990, 46, 34.
C10, E + Z, JHC10 125.2 Hz, JHCCC10 3.5–4.0 Hz, JHCC10 3.5–4.0 Hz],
1
3
2
22.28 [tm (s), C11, E + Z, JHC11 127.7 Hz], 13.99 [qm (s), C12, E + Z,
1
1JHC12 124.5–125.0 Hz]. 31P-{1H} NMR (36.46 MHz, CDCl3) dP: 56.8 (s),
56.6 (s). Found (%): C, 65.51; H, 11.34; N, 4.14; P, 9.41. Calc. for
C18H38NO2P (%): C, 65.22; H, 11.55; N, 4.23; P, 9.34.
Received: 11th September 2009; Com. 09/3392
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