α- and β-diphenylphosphorylated secondary alkanols: I. general method of synthesis and extraction properties towards f-elements

Article abstract of DOI:10.1134/S1070363216030208

A simple and effective general method of synthesis of α- and β-diphenylphosphorylated secondary alkanols by the reduction of the corresponding phosphorylalkanones with NaBH4 was developed. The extraction properties of the resulting phosphorylalkanols Ph

Full text of DOI:10.1134/S1070363216030208

ISSN 1070-3632, Russian Journal of General Chemistry, 2016, Vol. 86, No. 3, pp. 629–638. © Pleiades Publishing, Ltd., 2016.
Original Russian Text © E.I. Goryunov, A.G. Matveeva, A.M. Safiulina, I.B. Goryunova, G.V. Bodrin, V.K. Brel, 2016, published in Zhurnal Obshchei
Khimii, 2016, Vol. 86, No. 3, pp. 489–498.
To the 100th Anniversary of A.N. Pudovik
α- and β-Diphenylphosphorylated Secondary Alkanols:
I. General Method of Synthesis
and Extraction Properties Towards f-Elements
E. I. Goryunova, A. G. Matveevaa, A. M. Safiulinab,
I. B. Goryunovaa, G. V. Bodrina, and V. K. Brela
a Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences,
ul. Vavilova 28, Moscow, 119991 Russia
e-mail: phoc@ineos.ac.ru
b Uralchem United Chemical Company, Open Joint-Stock Company,
Presnenskaya nab. 6/2, Moscow, 123317 Russia
Received October 29, 2015
Abstract—A simple and effective general method of synthesis of α- and β-diphenylphosphorylated secondary
alkanols by the reduction of the corresponding phosphorylalkanones with NaBH4 was developed. The
extraction properties of the resulting phosphorylalkanols Ph2P(O)(CR2)nCH2CH(OH)Me (n = 0, 1; R = H, Me)
were studied in the recovery of f-elements (LaIII, NdIII, HoIII, YbIII, UVI, ThIV) from nitric acid solutions into
chloroform and compared with those of both related phosphorylketones and known extractants (n-BuO)3PO,
(n-C8H17)3PO, and Ph2P(O)CH2C(O)N(n-Bu)2.
Keywords: P,P-diphenylphosphorylalkanones, sodium borohydride, secondary P,P-diphenylphosphorylalkanols,
lanthanides, extraction
DOI: 10.1134/S1070363216030208
Solvent extraction is one of the methods most
commonly used for the recovery and separation of
elements with similar properties in hydrometallurgy
and spent nuclear fuel reprocessing [1–4]. The most
popular extractants in the industry are neutral
organophosphorus compounds of diverse types [4–7].
The efficiency of extraction processes is known to be
governed primarily by the choice of extractant that
should fit to specific and fairly stringent requirements
including high efficiency and selectivity in the
extraction of target metals, low cost, chemical stability,
easy stripping, etc. [1, 3–5].
phosphine oxide Ph2P(O)CH2C(O)NBu2, in the extrac-
tion of heavy lanthanides from HNO3 solutions into
chloroform [8–10]. Also, the first data on the recovery
of lanthanides from acidic media by micellar
extraction with the use of the same acetyl-containing
phosphine oxides as chelating agents [11] proved to be
very interesting. One of the most effective phos-
phorylketones, Ph2P(O)CHMeCH2C(O)Et, was used in
the development of extraction techniques for the
recovery of lanthanides from low-margin mineral raw
materials eudialyte [12] and phosphogypsum [13]. In
complexing with lanthanide cations phosphorylketones
typically exhibit P=O-monodentate coordination, but
in the presence of C=O group in the molecule of the
extractant its efficiency increases due presumably to
the involvement of the carbonyl group1 in additional
Recently, acetyl-containing phosphine oxides were
suggested as extractants for the separation of lantha-
nides. Compounds of this group R2P(O)–X–C(O)Me
(R = Alk, cyclo-Alk, Ph; X – various linkers) were
shown to be much more effective than the known
extractants, e.g., tributyl phosphate (BuO)3PO, trioctyl-
phosphine oxide (C8H17)3PO, and carbamoylmethyl-
1
The involvement is directly evidenced by high extraction
capability towards lanthanides, exhibited by phosphorylketone
Ph2P(O)CH2CH2C(O)Me compared to phosphine oxide
Ph2P(O)Bu-n [9].
629

630
GORYUNOV et al.
Scheme 1.
O
O
P
O
P
OH
CH
OH
CH
OH
CH
Ph
Ph
Ph
Ph
Ph
Ph
P
Me
Me
Me
Me
Me
1
2
3
O
O
O
O
BuO
C8H17
C8H17
Ph
Ph
Ph
Ph
Bu
Bu
P
BuO
BuO
P
O
P
P
O
Me
N
C8H17
4
6
5
7
Scheme 2.
O
O
O
C
OH
(1) NaBH4, 20oC, MeOH−H2O
Ph2P
Ph2P
(CH2)n
Me
(CH2)n CH Me
(2) H2SO4, 20oC
4, 8
1, 2
n = 1 (1, 4), 2 (2, 8).
weak interactions (hydrogen bonding, solvation, weak
coordination bonding, etc.). Hence it can be expected
that the modification of the structure of phosphine
oxides by introducing another additional donor center
which is not involved, or weakly involved, in coor-
dination will also lead to more effective and selective
extractants than unmodified prototypes. For example,
in the structure of phosphorylalkanols, along with the
phosphoryl group responsible for coordination, there is
a center able to participate in weak interactions, OH
group. In nonaqueous media phosphorylalkanols can
form associates2 (L–OH)n via intermolecular >P=O···HO–
bonds. In this case, it can be expected that the
extracted complexes will comprise not only the L–OH
molecules but also associated (L–OH)n particles,
whereby the extractability of the complexes will be
enhanced. The molecules and associates in such
complexes will form coordination bonds with f-
element cations via P=O group, and the size
(lipophilicity) of the coordinated ligand will increase
due to intermolecular hydrogen bonding. Aggregation
is well known to significantly improve the efficiency
of extraction by acidic podands and acids of phos-
phorus [14–19].
influence of the structure modification on the extrac-
tion properties of ligands.
The extraction capabilities of phosphorylalkanols
1–3 towards f-elements were examined by analyzing
how they are influenced by the structure of the linker
between the P=O and CH(OH) groups. As references
served phosphorylketone Ph2P(O)CH2C(O)Me which
is structurally related to alcohol 1, as well as known
organophosphorus extractants 5–7 (Scheme 1).
A number of α- and β-diphenylphosphorylated3
secondary alkanols was described in the literature, but
currently there exists no general simple, powerful, and
technologically effective method for the synthesis of
compounds of this type. It therefore seemed logical to
develop a method for direct reduction of structurally
similar phosphorylketones whose preparation metho-
dology is fairly well established (see, e.g., [20]). This
approach was tested on the synthesis of simplest α- and
β-diphenylphosphorylalkanols 1 and 2.
We found that the reduction of phosphorylated
acetone 4 and 4-(diphenylphosphoryl)butan-2-one 8 by
an excess of NaBH4 in a water-methanol medium
proceeds vigorously at room temperature with negligible
formation of byproducts and gives target phosphorylal-
kanols 1 and 2 in nearly quantitative yields (Scheme 2).
Here, we synthesized a series of phosphorylalka-
nols 1–3 which are structurally related to the pre-
viously studied phosphorylketones [9], and this
allowed us to subsequently assess most properly the
3
In this case, similarly to the previously studied phos-
phorylketones [9], compounds are considered in which the linker
between the Ph2P(O) and CH(OH) moieties contains no more
than two carbon atoms.
2
Along with associates, phosphorylalkanol molecules with intra-
molecular hydrogen bond can participate in the equilibrium.
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α- AND β-DIPHENYLPHOSPHORYLATED SECONDARY ALKANOLS: I.
631
Scheme 3.
O
O
O
C
CH3COOH
Ph2PCl + CH2
Ph2PCH2CH2C Me
CH
Me
~20oC, solvent
8
Compound 1 obtained by this method is an air-
stable white crystalline substance, mp 97.0–98.5°C.
Although it exhibits unusually large differences in the
physicochemical constants compared to those
presented in various publications,4 its structure was
unambiguously confirmed by NMR and X-ray
diffraction data.
Our experiments showed that in diethyl ether the
reaction was complete after 5 days (67.5% yield). By
contrast, the process was greatly accelerated when
methylene chloride was used as the solvent (reaction
time 8 h, 74.1% yield). In acetonitrile the reaction was
complete within 3 h (75.3% yield). Thus, the use of
MeCN significantly intensifies the synthesis of
phosphorylketone 8.6
As to alcohol 2, the most efficient reported
approach to its synthesis is based on the reaction of
CH2=CHCH(OH)CH3 with diphenylphosphinous acid
in a methanol-hexane medium at ~20°C in the
presence of catalytic amounts of Et3B, which affords
only 80% yield of the target alcohol [24]. The
preparation of alcohol 2 by the reduction of the
corresponding ketone that we have developed proceeds
under equally mild conditions but does not require the
use of catalysts and allows isolation of the target
product in a significantly higher yield.
Since both the synthesis of phosphorylketone 8 by
the Conant reaction7 and the reduction of this ketone
by sodium borohydride proceed at room temperature at
a fairly high rate without formation of any significant
amounts of byproducts, we could reasonably expect
that these processes might be effectively combined
into a single one-pot process.
Indeed, elimination of the stage of isolation of
ketone 8 as individual component in this case
substantially simplifies the procedure of preparation of
the target phosphoryl carbinol 2, with its yield
remaining very high, 90.9% (Scheme 4).
We also explored the possibility of using a two-step
one-pot process for preparation of β-diphenylphos-
phorylated secondary alkanols with the use of di-
phenylchlorophosphine as the initial organophosphorus
compound. The first step of this process, conversion of
Ph2PCl to 4-(diphenylphosphoryl)butan-2-ones, could
be based on the classical Conant reaction [25],5 which
is considered with good reason to be the best method
for the synthesis of phosphorylketones [26]. Today the
most efficient version of this reaction, which was
implemented for the synthesis of simplest β-diphenyl-
phosphorylated alkanone 8, is the reaction of Ph2PCl
with the corresponding α,β-enone in anhydrous
benzene at room temperature [27]. Unfortunately, a
significant drawback of this method is a low reaction
rate, with 42 h required for the reaction to go to
completion. We believed that the use of a different
solvent would significantly accelerate the process and
so studied the reaction in diethyl ether, methylene
chloride, and acetonitrile (Scheme 3).
Further, a similar one-pot process (Scheme 4) we
used equally successfully (87.6% yield) for obtaining a
previously unknown phosphorylalkanol 3, whose
structure was confirmed by spectral and X-ray diffrac-
tion data.
Thus, we showed that the reduction of diphenyl-
phosphorylalkanones with sodium borohydride in a
water-methanol medium is a simple general powerful
method for the synthesis of the corresponding α- and
β-diphenylphosphorylated secondary alkanols, and this
reaction is suitable in principle as the final stage of a
technologically effective one-pot processes.
The extraction capabilities of phosphorylalkanols
1–3 towards f-elements were studied in the extraction
of a group of lanthanides(III), as well as of ura-
nium(VI) and thorium(IV) from nitric acid water
solutions into chloroform at varied nitric acid con-
4
For example, in [21], where its preparation was first mentioned,
6
as well as in a later publication [22], alkanol 1 was isolated as a
high-boiling liquid. In a recent study [23], by contrast, secondary
alcohol 1 was obtained as a solid with mp 200–205°C (!).
According to our preliminary results, this technique can also be
successfully employed to improve the corresponding parameters
of the reaction of diphenylchlorophosphine with other types of
compounds containing the >C=CH–C(O)– moiety.
5
The reaction of Ph2PCl with α,β-enone in the presence of glacial
7
The reaction is run in anhydrous acetonitrile.
acetic acid.
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632
GORYUNOV et al.
Scheme 4.
O
O
O
C
CH3COOH
Ph2PCR2CH2 C Me
Ph2PCl + CR2 CH
Me
~20oC, MeCN
8, 9
O
NaBH4
OH
Ph2P
CR2CH2CH Me
~20oC, MeOH
2, 3
R = H (2, 8), Me (3, 9).
centration and constant concentrations of the salt in the
water phase and of the ligand in CHCl3. When
analyzing the distribution ratios (DM) as dependent on
the structure of phosphorylalkanols 1–3 we monitored
the influence of the structure of the linker between the
P(O) and CH(OH) moieties.
presence of a strongly coordinating P=O center, the
OH group of phosphorylalkanols can participate in
weak coordination interactions, thereby modifying the
extraction properties of the compound.
Studies of the solvent extraction of f-elements showed
that alcohol 1 effectively extracts lanthanides(III), with
DLn being 1.13–2.43 in the extraction from 4 M HNO3
(Fig. 1). Under the same experimental conditions
alcohols 2 and 3 show negligible extraction towards
lanthanides(III), with DLn not exceeding 0.03
throughout the HNO3 concentration range of 0.05–4 M
and increasing only slightly to DLn ≤ 0.1 in the
extraction from 5 and 6 M HNO3.
Structural data on metal complexes of phos-
phorylated alcohols are scarce. For example, in [28]
the structure of lanthanide and alkaline earth metal
complexes with alcohols Alk2P(O)CH2CH(OH)Alk'
and AlkP(O)[CH2CH(OH)Alk']2, patented as poly-
merization catalysts for carbonyl-containing or cyclic
monomers, was described. According to the X-ray
diffraction data [28], most of these complexes are
alkoxides, and those involving the AlkP(O)[CH2CH·
(O)Alk'][CH2CH(OH)Alk']– anion have the oxygen
atom of the OH group directed towards the metal
cation, suggesting a weak M→O(H) bond. The same
patent [28] contains information on the complexes
formed by the secondary alkanol (t-Bu)2P(O)CH2CH·
(OH)Bu-t with chlorides of divalent metals (Mg, Zn,
Sn), in which two alkanol molecules are coordinated to
the cation by oxygen atoms of the P=O and OH
groups. For example,8 in the complex [{t-Bu2P(O)·
CH2CH(OH)Bu-t}2(H2O)Mg]Cl2 the Mg→O(H) bond
length is 2.049 Å.
The NMR examination revealed the stability of the
phosphorylalkanols during extraction from 4 M HNO3
and their nearly equal solubilities in the water phase: c
~ 2 × 10–6 M in contact of 0.01 M solution of alkanol
in chloroform with water (according to inductively
coupled plasma atomic emission spectrometry data).
Unlike phosphorylalkanols 1–3, their related phos-
phorylketones Ph2P(O)CH2C(O)Me 4, Ph2P(O)CH2CH2·
C(O)Me 8, and Ph2P(O)CMe2CH2C(O)Me 9 exhibit
approximately equal extraction capabilities towards
lanthanides [9].
The distribution ratios for lanthanides in the
extraction by phosphorylalkanol 1 vary with the HNO3
concentration in the water phase in nearly identical
manner, exhibiting a growing trend (Fig. 1).
The involvement of the OH group in the coor-
dination was also revealed for the crystalline complex
[Ni{Ph2P(O)CH2CH2OH}4]2+·[NiCl4]2–, in which, ac-
cording to the X-ray diffraction data, all four mole-
cules of the phosphorylated primary alcohol exhibit
bidentate coordination via oxygen atoms of the P=O
and OH groups, with the Ni→O(H) bond being fairly
weak (bond length 2.576 Å) [29]. Thus, despite the
This pattern is exhibited by many extractants,
including related diphenylphosphorylated ketones [9],
with the main extractable species being presumably the
cationic and neutral complexes [Ln(L)n(NO3)2]+·(NO3)–
and [Ln(L)n(NO3)3]0 (n ≤ 3) occurring in equilibrium.
With growing HNO3 concentration the content of
better extractable neutral complexes should increase,
and so the distribution ratios tend to increase.
8
Unfortunately, the X-ray diffraction data were stated in patent
[28] very briefly and were not included in the Cambridge
Crystallographic Database.
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α- AND β-DIPHENYLPHOSPHORYLATED SECONDARY ALKANOLS: I.
633
DLn
DU
[HNO3], M
[HNO3], M
Fig. 1. Variation of the distribution ratios of lanthanides(III)
with HNO3 concentration in the extraction by ligand 1
(0.01 M solution in CHCl3): (1) Gd, (2) Nd, (3) Pr, (4) La,
(5) Yb, and (6) Ho.
Fig. 2. Variation of the distribution ratio of uranium(VI)
with HNO3 concentration in the extraction by ligands 1–3
(0.01 M solutions in CHCl3): (1) 1, (2) 2, and (3) 3.
Our experiments revealed fairly poor extraction of
UVI (Fig. 2) and negligible extraction of ThIV by all
alkanols studied. The extraction capabilities of the
most efficient alkanol 1 increase with increasing HNO3
concentration (DU 0.45 for 4 M HNO3, Fig. 2), and
those of ligands 2 and 3 are low (maximal DU of 0.15
and 0.18, respectively), being nearly independent of
the HNO3 concentration in the 2–4 M range.
also expected for ketone 4 in whose molecule both
functional groups (in this specific case, phosphoryl and
carbonyl groups), like in that of alkanol 1, are
separated by a methylene fragment, but the distribution
ratios of ketone 4 differ only slightly from those of
ketones 8 and 9 with the corresponding ethylene linker
[9]. Therefore, the assumption of the inertness of
phosphorylalkanols 2 and 3, observed in the extraction
experiments, as being due mainly to the different
structures of the complexes extracted is not exhaustive.
Presumably, the extraction properties of alkanols 1–3
are more strongly influenced by the difference in
aggregation than in coordination properties.
Thus, changes in the structure of the linker between
the P=O and CH(OH) groups produce radical changes
in the extraction properties of phosphorylated
secondary alkanols. Reasons for this unusual effect are
as yet unclear, but it can be presumed that the structure
of alcohol 1, by contrast to its homologs, is
considerably more favorable for the participation of
the OH group in additional interactions. For example,
bidentate coordination of ligand 1, similar to that
described for phosphorylalkanols Bu2P(O)CH2CH·
(OH)Bu-t [28] and Ph2P(O)CH2CH2OH [29], should
cause an increase in the stability of the extracted
complexes and, consequently, in the extraction
efficiency. For alkanols 2 and 3 the possible bidentate
coordination is less favorable, since it entails the
formation of seven- rather than six-membered metal
cycles. The bidentate coordination in the case of ligand
1 is more probable for lanthanides with large radii
from the beginning of the series. Consequently, the
efficiency of their extraction by phosphorylalkanol 1
should be higher than that of heavy lanthanides with
smaller radii, which was indeed the case in our
experiments (Fig. 1). Such bidentate coordination is
Metal extraction is significantly affected by
aggregation of ligands and their complexes in the
organic phase [14–19]. For example, phosphoryl-
containing acid podands and bisphosphonic acids
differing in the structure of the bridge between the
terminal groups form in organic solutions aggregates
with different numbers of particles, and the degree of
association in each group depends in a complicated
manner on the bridge structure [14–19]. The effect of
the aggregation state of compounds on the extraction
of metals and the formation of hydrogen bonds in
aggregates was examined earlier [14–19]. For
example, for related podands the differences in the size
and structure of the associates formed via hydrogen
bonds are responsible for 3–70-fold changes in the
distribution ratios of uranium(VI) and thorium(IV) [14,
30, 31]. At the same time for the phosphorylketones
Ph2P(O)(CR1R2)nCH2C(O)Me (n = 0, 1; R1, R2 = H,
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634
DM
GORYUNOV et al.
As to significant difference in the extraction
properties of phosphorylalkanols 1–3, one of the main
reasons for this is presumably the difference in their
hydrophilic-lipophilic properties, leading, in particular,
to higher aggregation states of both alcohol 1 and the
complexes extracted.
EXPERIMENTAL
The NMR spectra of 0.1 M solutions in CDCl3
were recorded on a Bruker AV-400 instrument
[400.13 (1H and 1H–{31P}), 100.61 (13C), and 161.98 MHz
(31P)]. The residual proton signals of the deuterated
1
solvent served as the internal reference for the H and
1H–{31P} NMR spectra, and the signals from the
carbon nuclei of the deuterated solvent, for the 13C
NMR spectra; 85% H3PO4 served as the external
reference for the 31P NMR spectra. The FTIR spectra
were measured on a Bruker Tensor 37 FTIR spectro-
meter (KBr pellets). Elemental analysis was performed
in the Laboratory of Microanalysis, Nesmeyanov
Institute of Organoelemental Compounds, Russian
Academy of Sciences.
Fig. 3. Comparison of the distribution ratios of LaIII, NdIII,
HoIII, YbIII, and UVI in the extraction into chloroform by
compounds 1 and 4–7 (0.01 M solutions in CHCl3) from
3.96 M HNO3; initial concentration of the lanthanide and
uranyl nitrates in the water phase 2.5 × 10–4 M.
Diphenylchlorophosphine (98%, Acros) was
purified by vacuum distillation just before the reaction;
all the manipulations with this compound were
performed under argon. Methyl vinyl ketone (95%,
Acros) and mesityl oxide (99%, Aldrich) were distilled
before the reaction at normal pressure over
hydroquinone. Glacial acetic acid (reagent grade) was
distilled just before use. Sodium borohydride (99%,
Acros) was used without further purification. Basic
Al2O3 Brockmann I (50–200 μm, Acros) and silica gel
(130–270 μm, 60 Å, Aldrich) were used. Diphenyl-
phosphorylated acetone 4 was synthesized and purified
by the known procedure described in [32].
Me, Ar, Het) which are not prone to self-association
DLn is weakly dependent on the structure of the linker
between P(O) and C(O) groups.
Further research is required to verify these
hypotheses, which is beyond the scope of this study.
The extraction properties of phosphorylated alcohol
1 were compared with those of related ketone 4 and
known mono- and bidentate phosphoryl-containing
extractants 5–7, studied under identical experimental
conditions. Figure 3 shows that alcohol 1 not only
more effectively extracts lanthanides from nitric acid
media than ketone 4 and known compounds 5–7 but
also exhibits a fairly high selectivity towards pairs of
heavy and light lanthanides. The separation factor for
the neodymium–holmium pair is 1.8, and that for the
gadolinium–holmium pair, 2.0. In the case of uranium,
reference ligands 6 and 7 proved to be more powerful
extractants, by contrast.
Acetonitrile (99.9%, Acros), methylene chloride
(reagent grade), and diethyl ether (reagent grade) were
dehydrated by standard procedures [33]. Other
solvents [methyl tert-butyl ether (99.8%, Acros),
hexane (reagent grade), methanol (reagent grade), and
chloroform (reagent grade)] were used without further
purification.
Thus, the transformation of phosphorylketone 4
into the corresponding alcohol 1 substantially im-
proves the extraction properties of the ligand with
respect to f-elements, particularly lanthanides. The
distribution ratios achieved with alcohol 1 exceed 2–3-
fold those with ketone 4 in the extraction of light
lanthanides, and 1.2–1.7-fold in the extraction of heavy
lanthanides and uranium.
Model compounds tributyl phosphate (n-BuO)3PO
5 (99%, Acros) and trioctylphosphine oxide (n-C8H17)PO
6 (98%, Acros) were used without further purification;
(N,N-dibutylcarbamoylmethyl)diphenylphosphine
oxide Ph2P(O)CH2C(O)N(Bu-n)2 7 was synthesized
and purified in accordance with the known technique
from [34].
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α- AND β-DIPHENYLPHOSPHORYLATED SECONDARY ALKANOLS: I.
635
1-(Diphenylphosphoryl)propan-2-ol (1). To a
solution of 2.0 g (7.74 mmol) of diphenylphos-
phorylated acetone 4 in 20 mL of methanol, a solution
of 150 mg (3.94 mmol) of NaBH4 in 4 mL of distilled
water was added dropwise with stirring. The resulting
mixture was stirred for 4 h at room temperature and
left overnight, then diluted with an equal volume of
distilled water, acidified to pH ≤ 3 with dilute (1 : 3)
H2SO4, and extracted with chloroform (4 × 15 mL).
The extract was washed successively with distilled
water (3 × 10 mL) and saturated water solution of
NaHCO3 (2 × 5 mL) and then dried over anhydrous
MgSO4. The solvent was removed in a vacuum, and
the residue was washed successively with 11 mL of
hexane–ether (10 : 1) mixture and 10 mL of hexane
and then dried in a vacuum (~15 Torr) for 1 h at ~20°C.
Yield 1.92 g (95%), mp 97.0–98.5°C.9 IR spectrum, ν,
volatiles were removed under a water-jet pump
(~10 Torr). The residue was kept in a vacuum
(~1 Torr) for 2.5 h at ~55°C, then dissolved in 10 mL
of CH2Cl2, and filtered sequentially through 1.3 g of
basic Al2O3 and 1.3 g of silica gel; the carrier was
washed with 6 mL of CH2Cl2 each time. The solvent
was removed from the filtrate under vacuum, and the
residue was recrystallized from methyl tert-butyl ether.
Yield 1.27 g (77.8%), mp 98.5–100°C (mp 105–106°C
[35]). IR spectrum, ν, cm–1: 1185 (P=O), 1720 (C=O).
1H NMR spectrum, δ, ppm: 2.09 s (3H, CH3), 2.47–
2.57 m (2H, CH2P), 2.70–2.79 m [2H, CH2C(O)],
7.40–7.54 m (6H, m,p-C6H5), 7.67–7.76 m (4H, o-
1
C6H5). H–{31P} NMR spectrum, δ, ppm: 2.09 s (3H,
CH3), 2.47–2.56 m (2H, CH2P), 2.70–2.78 m [2H,
CH2C(O)], 7.41–7.47 m (4H, m-C6H5), 7.48–7.53 m
(2H, p-C6H5,), 7.71 d (4H, o-C6H5, 3JHH = 7.6 Hz). 13C
cm–1: 1169 (P=O), 3325 (OH). H NMR spectrum, δ,
NMR spectrum, δC, ppm (J, Hz): 23.16 d (CH2P, 1JCP
=
1
ppm (J, Hz): 1.27 d.d (3H, CH3, 3JHH = 6.1, 4JHP = 1.4),
73.9), 29.61 s (CH3), 35.08 d (CH2CH2P, JCP = 2.4),
2
2.35 d.d.d (1H, CHAHB, 3JH H
A
= 2.2, 2JH P
A
= 7.5, 2JH H
A
B
=
=
128.62 d (m-C6H5, JCP = 11.8), 130.59 d (o-C6H5,
3
3
2
4
14.9), 2.46 d.d.d (1H, CHAHB, JH H
B
= 9.9, JH P
B
2JCP = 9.1), 131.81 d (p-C6H5, JCP = 2.7), 132.28 d
11.7, 2JH H
A
B
= 14.9), 4.18–4.30 m [1H, CH(OH)], 4.50
(ipso-C6H5, JCP = 99.6), 206.06 d (C=O, JCP = 13.5).
31P NMR spectrum: δP 32.37 ppm. Found, %: C 70.68;
H 6.39; P 11.49. C16H17O2P. Calculated, %: C 70.58; H
6.29; P 11.38.
1
3
br.s (1H, OH), 7.42–7.57 m (6H, m,p-C6H5), 7.66–7.78
1
m (4H, o-C6H5). H–{31P} NMR spectrum, δ, ppm (J,
3
Hz): 1.27 d (3H, CH3, JHH = 6.1), 2.35 d.d (1H,
3
2
CHAHB, JH H
A
= 2.1, JH H
A
B
= 14.9), 2.46 d.d (1H,
3
2
4-(Diphenylphosphoryl)butan-2-ol (2). a. To a
solution of 1.0 g (3.67 mmol) of ketone 8 in 10 mL of
methanol, a solution of 70 mg (1.86 mmol) of NaBH4
in 2 mL of distilled water was added dropwise with
stirring. The resulting mixture was stirred for 4 h at
room temperature, left overnight, and then treated as
described above for compound 1. After removal of the
solvent from the extract the residue was dried for 3 h at
50–60°C in a vacuum (~1 Torr). Yield 0.971 g
(96.5%), mp 101.5–103.5°C (mp 101–102°C [36]). IR
spectrum, ν, cm–1: 1159, 1182 sh (P=O), 3500 sh,
CHAHB, JH H
B
= 9.8, JH H
A B
= 14.9), 4.19–4.29 m [1H,
CH(OH)], 4.47 br.s (1H, OH), 7.43–7.57 m (6H, m,p-
C6H5), 7.67–7.77 m (4H, o-C6H5). 13C NMR spectrum,
3
δC, ppm (J, Hz): 24.75 d (CH3, JCP = 14.2), 37.94 d
1
2
(CH2, JCP = 71.2), 63.18 d (CH, JCP = 4.7), 128.68 d
3
2
(m-C6H5, JCP = 11.5), 130.27 d (o-C6H5, JCP = 9.8),
2
130.83 d (o-C6H5, JCP = 9.4), 131.83 d (ipso-C6H5,
1JCP = 98.2), 131.92 d (p-C6H5, JCP = 2.7), 131.98 d
4
(p-C6H5, 4JCP = 2.7), 133.16 d (ipso-C6H5, 1JCP = 99.6).
31P NMR spectrum: δP 33.91 ppm. Found, %: C 69.28;
H 6.65; P 11.88. C15H17O2P. Calculated, %: C 69.22; H
6.58; P 11.90.
1
3325, 3330 sh (OH). H NMR spectrum, δ, ppm (J,
3
Hz): 1.19 d (3H, CH3, JHH = 6.2), 1.69 d.d.d.d.d (1H,
4-(Diphenylphosphoryl)butan-2-one (8).10 To a
solution of 0.44 g (6.3 mmol) of methyl vinyl ketone
in 5 mL of anhydrous acetonitrile, a solution of 0.41 g
(6.7 mmol) of glacial AcOH in 3 mL of anhydrous
acetonitrile and a solution of 1.32 g (6 mmol) of
Ph2PCl in 3 mL of anhydrous acetonitrile were added
sequentially dropwise. The resulting mixture was kept
for 3 h at room temperature, and the solvent and other
2
3
3
CHAHBCH, JH H
A
B
= 14.5, JH H
A
A
= 8.2, JH HA' = 8.2,
A
3
3JH H
A
B' = 6.6, JH P
= 12.9), 1.85 d.d.d.d.d (1H,
2
3
3
CHAHBCH, JH H
B
A
= 14.3, JH H
B
= 3.3, JH HA' = 6.5,
B
3JH H
B
B' = 8.5, 3JH 3P
B
= 14.3), 2.41 d.d.d.d (1H, PCHA'HB',
2JHA' B' = 15.2, JHA'
A
= 8.3, JHA'
B
= 6.5, JHA'
=
3
2
H
H
H
P
2
11.5), 2.48 d.d.d.d (1H, PCHA'HB', JHB' A' = 15.2,
H
3
2
3JHB'
A
= 6.7, JHB'
B
= 8.5, JHB' = = 11.4), 3.50–3.80
H
H
P
3
br.s (1H, OH), 3.90 d.d.q [1H, CH(OH), JHH = 6.2,
3
3JHH
A
= 8.4, JHH = 3.4], 7.44–7.50 m (4H, m-C6H5),
B
9
After recrystallization from the hexane–CHCl3 mixture the
7.50–7.56 m (2H, p-C6H5), 7.72–7.79 m (4H, o-C6H5).
melting point remains unchanged.
13C NMR spectrum, δC, ppm (J, Hz): 23.32 s (CH3),
10 The most powerful technique for the synthesis of 8 in an
acetonitrile medium is presented.
26.45 d (CH2P, 1JCP = 71.9), 31.24 d (CH2CH2P, 2JCP
=
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 86 No. 3 2016

636
GORYUNOV et al.
3
3.7), 67.50 d (CH, JCP = 10.3), 128.71 d (m-C6H5,
volatiles were removed in
a
water-jet pump
3JCP = 11.7), 128.73 d (m-C6H5, JCP = 11.7), 130.80 d
(~10 Torr). The residue was kept under vacuum
(~1 Torr) for 2.5 h at ~55°C and then dissolved in
30 mL of CH2Cl2. The resulting solution was filtered
through 5.0 g of basic Al2O3; the carrier was washed
with 15 mL of CH2Cl2. The filtrate was evaporated in a
vacuum (~10 Torr), and the residue was kept under
vacuum (~1 Torr) for 2 h at ~55°C. As a result, 6.841 g
(~100%) of crystalline 4-(diphenylphosphoryl)-4-
methylpentan-2-one 9 with ~97% purity according to
the 31P NMR data was obtained. The product was
dissolved in 60 mL of methanol, and to the resulting
solution a solution of 0.866 g (22.8 mmol) of NaBH4
in 24 mL of distilled water was added dropwise. The
mixture was stirred for 3 h at room temperature, left
overnight, and then treated as described above for
compound 1. After removal of the solvent the residue
was dried for 3 h at 50–60°C in a vacuum (~1 Torr),
refluxed in 60 mL of hexane–ether (57 : 3) mixture,
and then cooled to 0°C. The resulting precipitate was
separated, washed with hexane–ether (57 : 3) mixture
(2 × 30 mL) and air-dried. Yield 6.038 g (87.6%), mp
126.5–127.5°C. IR spectrum, ν, cm–1: 1159, 1182
3
2
2
(o-C6H5, JCP = 9.5), 130.84 d (o-C6H5, JCP = 8.8),
131.81 d (p-C6H5, 4JCP = 2.9), 131.84 d (p-C6H5, 4JCP
2.9), 132.54 d (ipso-C6H5, 1JCP = 99.0), 132.57 d (ipso-
=
1
31
C6H5, JCP = 98.3). P NMR spectrum: δP 34.54 ppm.
Found, %: C 70.05; H 7.11; P 11.22. C16H19O2P.
Calculated, %: C 70.06; H 6.98; P 11.29.
b. To a solution of 1.802 g (25.7 mmol) of methyl
vinyl ketone in 10 mL of anhydrous acetonitrile, a
solution of 1.553 g (25.8 mmol) of glacial AcOH in
7 mL of anhydrous acetonitrile and a solution of 5.037 g
(22.8 mmol) of Ph2PCl in 7 mL of anhydrous
acetonitrile were added sequentially dropwise. The
reaction mixture was kept for 3 h at room temperature,
and the solvent and other volatiles were removed under
a water-jet pump (~10 Torr). The residue was kept
under vacuum (~1 Torr) for 2.5 h at ~55°C and then
dissolved in 30 mL of CH2Cl2. The resulting solution
was filtered through 5.0 g of basic Al2O3, and the
carrier was washed with 15 mL of CH2Cl2. The solvent
was removed from the filtrate under a water-jet pump
(~10 Torr), and the residue was kept under vacuum
(~1 Torr) for 2 h at ~55°C. As a result, 5.983 g (~96%)
of crystalline ketone 8 with ~99% purity according to
the 31P NMR data was obtained. The product was
dissolved in 60 mL of methanol, and to the resulting
solution a solution of 0.866 g (22.8 mmol) of NaBH4 in
24 mL of distilled water was added dropwise. The
mixture was stirred for 3 h at room temperature, left
overnight, and then treated as described above for
compound 1. After removal of the solvent the residue
was dried for 3 h at 50–60°C in a vacuum (~1 Torr),
refluxed in 60 mL of hexane–ether (57 : 3) mixture,
and then cooled to 0°C. The resulting precipitate was
separated, washed with hexane–ether (57 : 3) mixture
(2 × 30 mL) and air-dried. Yield 5.479 g (90.9%), mp
102–104°C. Found, %: C 70.05; H 7.07; P 11.24.
C16H19O2P. Calculated, %: C 70.06; H, 6.98; P 11.29.
The spectral characteristics of the resulting compound
were identical to those of the sample obtained by
method a.
1
(P=O), 3500 sh, 3390, 3330 sh (OH). H NMR
3
spectrum, δ, ppm (J, Hz): 1.15 d (3H, CH3CH, JHH
=
A
3
6.2), 1.30 d (3H, CH3 CP, JHP = 15.6), 1.31 d (3H,
B
3
2
CH3 CP, JHP = 14.7), 1.44 d.d (1H, CHAHB, JH H
A
B
=
=
=
3
2
15.2, JH P
A
= 25.6), 1.93 d.d.d (1H, CHAHB, JH H
B
A
3
3
3
15.2, JH P
B
= JH H = 10.0), 4.12 d.q (1H, CH, JHH
B
6.2, 3JHH
B
= 9.5), 5.64 br.s (1H, OH), 7.47–7.61 m (6H,
m,p-C6H5), 7.93–8.05 m (4H, o-C6H5). 13C NMR
B
spectrum, δC, ppm (J, Hz): 22.13 s (CH3 CP), 24.35 s
A
2
(CH3CH), 26.76 d (CH3 CP, JCP = 2.3), 37.17 d
1
(PCMe2, JCP = 68.7), 49.97 s (CH2), 62.90 d (CH,
3JCP = 1,5), 128.44 d (m-C6H5, JCP = 10.7), 128.52 d
3
3
1
(m-C6H5, JCP = 10.7), 129.89 d (ipso-C6H5, JCP
=
1
90.8), 130.12 d (ipso-C6H5, JCP = 93.1), 131.88 s (p-
2
C6H5), 132.33 d (o-C6H5, JCP = 8.4), 132.51 (o-C6H5,
31
2JCP = 8.4). P NMR spectrum: δP 42.80 ppm. Found,
%: C 71.54; H 7.67; P 10.21. C18H23O2P. Calculated,
%: C 71.50; H 7.67; P 10.24.
Study of the extraction capabilities of com-
pounds (1–7). For the preparation of solutions we used
bidistilled water, CHCl3 (reagent grade), arsenazo III
(analytical grade), HNO3 (high purity grade), UO2(NO3)2·
6H2O (reagent grade), Th(NO3)4·4H2O (reagent grade),
La(NO3)3·6H2O (reagent grade), Pr(NO3)3· 6H2O
(reagent grade), Nd(NO3)3·6H2O (reagent grade), Gd
(NO3)3·6H2O (pure grade), Ho(NO3)3·6H2O (pure
grade), and Yb(NO3)3·6H2O (pure grade). The
4-(Diphenylphosphoryl)-4-methylpentan-2-ol (3).
To a solution of 2.522 g (25.7 mmol) of mesityl oxide
in 10 mL of anhydrous acetonitrile, a solution of 1.553 g
(25.8 mmol) of glacial AcOH in 7 mL of anhydrous
acetonitrile and a solution of 5.037 g (22.8 mmol) of
Ph2PCl in 7 mL of anhydrous acetonitrile were added
sequentially dropwise. The reaction mixture was kept
for 24 h at room temperature, and the solvent and other
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α- AND β-DIPHENYLPHOSPHORYLATED SECONDARY ALKANOLS: I.
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ACKNOWLEDGMENTS
This study was financially supported by the Russian
Foundation for Basic Research (project no. 14-03-
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