Phosphine-catalyzed synthesis of unsymmetrical 1,3-bis- and trisphosphorus ligands

Article abstract of DOI:10.1055/s-0029-1217176

Phosphine-catalyzed umpolung γ-additions of phosphorus pronucleophiles on alkynes bearing phosphinoyl (P=O) or phosphinothioyl (P=S) moieties have been explored. The reaction leads to bis- or trisphosphorus subunits that can be useful for the preparation of chelating ligands. Georg Thieme Verlag Stuttgart.

Full text of DOI:10.1055/s-0029-1217176

1466
LETTER
Phosphine-Catalyzed Synthesis of Unsymmetrical 1,3-Bis- and
Trisphosphorus Ligands
Synthesis of
U
nsym
i
metrical 1,3
L
-Bis-
a
nd Trisp
i
hospho
n
rus Ligands, Dan Bernardi, Eric Doris, Frédéric Taran*
CEA, iBiTecS, Service de Chimie Bioorganique et de Marquage, Gif sur Yvette 91191, France
Fax +33(1)69087991; E-mail: frederic.taran@cea.fr
Received 22 January 2009
The preparation of the starting alkynes 1 was achieved us-
ing a conventional route (Scheme 2). Compounds 1a,b
were obtained by reaction of propynyl magnesium bro-
mide on the corresponding phosphinic chloride at –78 °C.
Abstract: Phosphine-catalyzed umpolung g-additions of phospho-
rus pronucleophiles on alkynes bearing phosphinoyl (P=O) or phos-
phinothioyl (P=S) moieties have been explored. The reaction leads
to bis- or trisphosphorus subunits that can be useful for the prepara-
tion of chelating ligands.
With the objective to synthesize mixed 1,3-phosphinoyl/
phosphinothioyl P(O)/P(S) ligands, we also prepared the
sulfur containing alkyne 1c that will be used as model sub-
strate. Alkyne 1c was obtained in satisfactory yield by re-
acting 1a with Lawesson’s reagent (Scheme 2).
Key words: addition reactions, catalysis, umpolung, chelates,
phosphorus
Among known metal chelating subunits, phosphorus-
based functions are of considerable importance in coordi-
nation chemistry.1 Because of their strong metal ion com-
plexing ability, bis- and trisphosphorus compounds are
commonly used as efficient bi- or tridentate ligands for
metal sequestration. In this context, new and efficient syn-
thetic methods for the preparation of this important class
of organophosphorus products are of key interest.2
To study the g-P-addition, the reaction of diphenylphos-
phine oxide with alkyne 1a was chosen as the model reac-
tion (Scheme 3).
Our first attempts showed that the g-P-addition was trick-
ier compared to the a-P-addition reaction (Table 1). In-
deed, prolonged heating of reactants in the presence of 20
mol% of the phosphine catalyst afforded only traces of the
desired product (entries 1 and 2, Table 1). After numerous
unsuccessful attempts, microwave irradiation in 2-PrOH
was found to be the most efficient method to obtain good
yields of product 2a (entry 7, Table 1).
In connection with our efforts to develop new synthetic
routes to bisphosphorus actinide ligands,3 we have recent-
ly described the phosphine-catalyzed a-P-addition on
phosphinoyl alkynes, leading to P–C–P backbones4
(Scheme 1, upper part). In this paper, we would like to re-
port the extension of this process to the preparation of 1,3-
diphosphane oxides 4. The designed route to compounds
4 involves a Bu3P-catalyzed g-addition of phosphorus
pronucleophiles on activated alkynes 1, as the key step
(Scheme 1, lower part). Phosphines are known to impart
the electronic character to the g-carbon of acetylenic
esters and promote C–C,5 C–O,6 or C–N7 bond formation
in the presence of various pronucleophiles. Following our
results on the Bu3P-catalyzed a-C–P bond formation,4 we
envisaged that such chemistry could be extended to g-P-
addition by using the appropriate phosphorus-based pro-
nucleophiles and alkynes. Thus, reaction of 1-(phosphane
oxide)-propyne 1 with H-phosphane oxide pronucleo-
philes in the presence of catalytic amounts of Bu3P should
generate 1,3-diphosphoryl(phosphonyl, phosphinyl)-pro-
penes 2 and 3 whose double bond could be hydrogenated
to afford the desired products 4.
To look at the scope and limitations of this new reaction
we ran a series of g-additions under the optimized condi-
tions (Scheme 4, Table 2). The reaction generated, in each
case, a mixture of Z- and E-isomers of g-adducts 2 and 3
in moderate to good yields. It has to be pointed out that
compounds 2 and 3 were not formed in the absence of
Bu3P. The only products observed in this case are classical
Michael adducts resulting from the 1,4-addition of H-
phosphane oxide.
After isolation by flash chromatography of 2 and 3 from
the crude product, the mixture of isomers (2/3) was sub-
jected to hydrogenation to afford a single product 4 in
high yield. However, in the case of sulfur-containing com-
pounds 2g/3g, hydrogenation proceeded less readily and
required 1.5 equivalents of Pd/C and high pressure (50
bar) to generate the expected product 4g. Notably was that
the mixture of isomers 2h/3h failed to react, even under
these forcing conditions.
This synthetic route, based on phosphine-catalyzed um-
polung g-addition, allows the control of the nature of the
two phosphorus moieties and therefore is well adapted to
the preparation of unsymmetrical 1,3-bisphosphorus com-
pounds. The latter are usually difficult to synthesize by
classical methods.8
Overall, the double bond incorporated in the skeleton of 2
and 3 was found to display very poor reactivity and func-
tionalization attempts using, for example, Michael addi-
tion reactions with amines, Rli, or RMgX were
unsuccessful.
Bu3P
(20% mol)
O
O
O
O
SYNLETT 2009, No. 9, pp 1466–1470
x
x.
x
x.
2
0
0
9
P
P
+
H
P
Ph
P
Ph
Ph
Ph
Advanced online publication: 13.05.2009
DOI: 10.1055/s-0029-1217176; Art ID: D02709ST
Ph
Ph
Ph
Ph
1a
2a
© Georg Thieme Verlag Stuttgart · New York

LETTER
Synthesis of Unsymmetrical 1,3-Bis- and Trisphosphorus Ligands
1467
O
O
R2
P
H
R2 P–
ref. 4
Bu
P+
Bu
P+
Bu
Bu
R2
Bu
Bu
R2
Bu3P
O
P
(20% mol)
R1
R1
–
Ar
toluene, Δ
Ar
P O
Ar
P
R1
O
R1
R1
R1
α-addition
R2
R2
P
Bu
P+
2 R2
R
R2
H+
transfer
R2
Bu
Bu
P
O
O
O
O
P
O
O
NaBH4
–
– Bu3P
Ar
P
Ar
P
R1
Ar
P
R1
R1
R1
R1
R1
this work
R1
H+
transfer
R1
P
R1
O
P
+
P
Bu
Bu
Bu
P
R1
R1
Bu3P
Bu
Bu
Bu
+
P
–
O
–
R1
O
1
O
P
R2
H
R2
O
P
γ-addition
R2
R2
O
P–
R1
R1
O
R2
+
P
Bu
Bu
P
–
R2
Bu
R1
R1
+
P
Bu
Bu
Bu
P
H+
transfer
O
O
P
O
R2
R2
R2
R1
P
P
R1
R1
R2
–
R1
O
+
P
Bu
Bu
Bu
Bu
Bu
Bu
+
P
P
O
–
– PBu3
– Bu3P
R1
R1
R1
R1
R1
R1
O
P
P
O
P
O
H2, Pd/C
O
O
+
P
R2
P
O
P
R2
R2
R2
R2
3
2
R2
4
Scheme 1 Routes to unsymmetrical phosphorus ligands using phosphine-catalyzed umpolung additions
O
S
P
R
O
Lawesson's reagent
MgBr
P
R
Ph
Ph
Cl
P
R
Ph
THF
–78 °C to r.t.
toluene
reflux, 16 h
1a R = Ph, 96%
1b R = Me, 68%
1c R = Ph, 56%
Scheme 2 Preparation of compounds 1
Scheme 3 Model reaction under investigation
Compound 1d was then reacted with 3 equivalents of di-
ethylphosphite under microwave irradiation. The reaction
resulted in double g-P-addition of HP(O)(OEt)2 on 1d.
Catalytic hydrogenation of the crude mixture finally af-
forded the desired trisphosphane oxide 4h in satisfactory
yield.
The same strategy was also applied to the preparation of
trisphosphane oxide 4h starting from bisalkyne 1d which
was prepared by double addition of propynyl magnesium
bromide on dichlorophenylphosphine oxide (Scheme 5).
Synlett 2009, No. 9, 1466–1470 © Thieme Stuttgart · New York

1468
Y. Lin et al.
LETTER
O
X
P
R3
P
R2
Bu3P
2
X
P
R1
R1
O
P
R3
O
R2
X
(20% mol)
H2, Pd/C
EtOH
Ph
P
R3
P
R2
+
+
Ph
H
R1
MW
i-PrOH, –150 °C
30 min
Ph
O
R2
X
4
1
P
R3
P
3
R1
Ph
Scheme 4 Preparation of unsymmetrical bisphosphorus ligands 4
Table 1 Optimization of the Model Reactiona
Table 2 Scope of the Reaction
Entry R
R¢
R¢¢
X
Yield (%)a Product 4
of 2 and 3 (yield, %)a
(2:3 ratio)
Entry
Conditions
Yield of 2a (%)b
1
2
3
4
5
6
7
EtOH, 80 °C, 6 h
traces
traces
27
toluene, 110 °C, 6 h
O
P
O
P
1
2
3
4
5
6
Ph
Ph
Ph
Ph
Me
Me
Ph
Ph
O
O
O
O
O
O
2a 72 (–)
Ph
EtOH, MW, 150 °C, 30 min
DME, MW, 150 °C, 30 min
MeCN, MW, 150 °C, 30 min
t-BuOH, MW, 150 °C, 30 min
i-PrOH, MW, 150 °C, 30 min
Ph
Ph
Ph
4a 96
O
traces
traces
traces
72
O
2b/3b 74
(50:50)
P
P
OEt OEt
OEt Ph
EtO
Ph
Ph
OEt
4b 90
O
O
2c/3c 78
(56:44)
P
P
EtO
a Reactions were conducted with 1.1 equiv of Ph2P(O)H at 0.1 M.
b Isolated yields.
Ph
Ph
Ph
4c 89
O
O
2d/3d 25
(72:28)
O
O
P
P
Me
Me
MgBr
Me
Ph
Ph
Cl
P
P
Cl
Me
THF
–78 °C to r.t.
Ph
Ph
4d 94
1d 88%
O
O
2e/3e 45
(37:63)
P
P
OEt OEt
OEt Ph
OEt OEt
EtO
O
Me
Ph
OEt
1)
(3 equiv)
H
P
OEt
4e 99
O
OEt
O
Bu3P (20% mol)
2f/3f 49
(18:82)
P
P
EtO
MW
Me
Ph
Ph
i-PrOH, 150 °C, 30 min
4f 99
O
2) H2, Pd/C
S
2g/3g 26
(58:42)
O
O
P
P
7
8
Ph
Ph
S
S
EtO
EtO
OEt
P
Ph
Ph
P
OEt
O
P
OEt
EtO
4g 90
2h/3h 34
(50:50)
Ph
Ph
no reaction
Ph
4h 41%
a Isolated yields.
Scheme 5 Preparation of trisphosphorus ligand 4h
In conclusion, we have developed a new method for the
synthesis of symmetrical or unsymmetrical 1,3-phos-
phane oxides compounds using g-P-addition on activated
propynes. The reaction proceeds under microwave irradi-
ation within 30 minutes, and the resulting mixture of iso-
mers was successfully reduced to the final products by
hydrogenation.9 This method is complementary to others
known procedures but only requires two steps and is
straightforward for the synthesis of 1,3-phosphane oxides.
This reaction may also be used for the preparation of un-
symmetrical 1,3-bisphosphines that are of interest in ca-
talysis by complete reduction of products 2 and 3.10
Acknowledgment
This work is part of the ‘ChelAn’ project supported by the National
Research Agency (ANR) of France. We thank E. Zekri and D. Buis-
son for experimental assistance with MS and LC-MS measure-
ments.
References and Notes
(1) Irving, H. M. In Comprehensive Coordination Chemistry,
Vol. 1; Wilkinson, G. G.; Gillard, R. D.; McCleverty, J. A.,
Eds.; Pergamon Press: Oxford, 1987, 542.
Synlett 2009, No. 9, 1466–1470 © Thieme Stuttgart · New York

LETTER
Synthesis of Unsymmetrical 1,3-Bis- and Trisphosphorus Ligands
1469
(2) (a) Cristau, H.-J.; Virieux, D.; Mouchet, P.; Fruchier, A. Eur.
J. Org. Chem. 1999, 1561. (b) Antczak, M. I.; Montchamp,
J.-L. Tetrahedron Lett. 2008, 49, 5909. (c) Gouault-
Bironneau, S.; Deprèle, S.; Sutor, A.; Montchamp, J.-P. Org.
Lett. 2005, 7, 5909. (d) Inoue, S.; Okauchi, T.; Minami, T.
Synthesis 2003, 1971.
(3) (a) Lecerclé, D.; Gabillet, S.; Gomis, J.-M.; Taran, F.
Tetrahedron Lett. 2008, 49, 2083. (b) Lecerclé, D.; Taran,
F. Synlett 2007, 12, 1863. (c) Sawicki, M.; Siaugue, J. M.;
Jacopin, C.; Moulin, C.; Bailly, T.; Burgada, R.; Meunier, S.;
Baret, P.; Pierre, J. L.; Taran, F. Chem Eur. J. 2005, 11,
3689.
(4) Lecerclé, D.; Sawicki, M.; Taran, F. Org. Lett. 2006, 8,
4283.
(5) (a) Trost, B. M.; Li, C.-J. J. Am. Chem. Soc. 1994, 116,
3167. (b) Alvarez-Ibarra, C.; Csakÿ, A. C.;
Gomez de la Olivia, C. J. Org. Chem. 2000, 65, 3544.
(c) Lu, X.; Zhang, C.; Xu, Z. Acc. Chem. Res. 2001, 34, 535.
(6) (a) Trost, B. M.; Li, C.-J. J. Am. Chem. Soc. 1994, 116,
10819. (b) Alvarez-Ibarra, C.; Csakÿ, A. C.;
(160 MHz, CDCl3): d = –20.76 ppm. MS (ESI/TOF):
m/z = 203 [M + H]+.
General Procedure for g-P-Addition Reaction
The mixture of compound 1 (1 equiv), phosphorus
pronucleophiles (1.2 equiv), and tributylphosphine (0.2
equiv) in 2-PrOH was irradiated under microwave for 30
min at 150 °C. The solvent was evaporated under vacuum,
and the product was purified by column chromatography on
SiO2 (eluent: acetone).
Compound 2a: white solid, mp 87–90 °C. 1H NMR (400
MHz, CDCl3): d = 3.36 (dd, J = 7.6 Hz, J = 15.2 Hz, 2 H),
6.34–6.46 (m, 1 H), 6.47–6.60 (m, 1 H), 7.33–7.56 (m, 16
H), 7.69–7.75 (m, 4 H) ppm. 13C NMR (100 MHz, CDCl3):
d = 36.61 (d, J = 17 Hz), 37.25 (d, J = 17 Hz), 128.45 (d,
J = 12 Hz), 128.76 (d, J = 12 Hz), 129.44 (d, J = 10 Hz),
130.86 (d, J = 10 Hz), 131.25 (d, J = 10 Hz), 131.76 (d, J = 3
Hz), 131.61, 132.12 (d, J = 2 Hz), 132.19, 132.66, 140.17–
140.30 (m)ppm. 31P NMR (160 MHz, CDCl3): d = 23.38,
23.42, 28.96, 29.00 ppm. MS (ESI/TOF): m/z = 443 [M +
H]+.
Gomez de la Olivia, C. Tetrahedron Lett. 1999, 40, 8465.
(7) Trost, B. M.; Li, C.-J. J. Org. Chem. 1997, 62, 5670.
(8) (a) Lu, X.; Tao, X.; Zhu, J.; Sun, X.; Xu, J. Synthesis 1989,
848. (b) Grushin, V. V. Chem. Rev. 2004, 104, 1629.
(c) Kauffmann, T.; Antfang, E.; Olbrich, J. Tetrahedron Lett.
1984, 25, 1963. (d) Han, L.-B.; Zhao, C.-Q. J. Org. Chem.
2005, 70, 10121. (e) Benn, R. F.; Briggs, J. C.; McAuliffe,
C. A. J. Chem. Soc., Dalton Trans. 1984, 293.
(9) General Procedure for the Preparation of Compounds 1
To a soln of phosphoric chloride (5.5 mmol) in dry THF
propynylmagnesium bromide (10 mL, 5 mmol, 0.5 M in
THF) was added dropwise under Ar at –78 °C. The mixture
was stirred at this temperature for 2 h, diluted with Et2O,
washed with a sat. soln of NH4Cl and brine, dried over
MgSO4, filtered, and concentrated under vacuum. The crude
residue was purified by column chromatography on SiO2
(eluent: EtOAc–cyclohexane = 8:2).
General Procedure for Hydrogenation of Compounds 2
and 3
A mixture of 2 and 3 was hydrogenated using Pd/C (0.03
equiv of 10% Pd/C) catalyst in EtOH at r.t. for 24 h. After
filtration, the residue was washed with EtOH (3×). The
combined organic phases were evaporated to give desired
product.
Compound 4a: white solid, mp 142–144 °C. 1H NMR (400
MHz, CDCl3): d = 1.91–2.02 (m, 2 H), 2.43–2.50 (m, 4 H),
7.35–7.46 (m, 12 H), 7.63–7.66 (m, 8 H) ppm. 13C NMR
(100 MHz, CDCl3): d = 14.85, 29.95 (dd, J = 11, 71 Hz),
128.59 (d, J = 12 Hz), 130.61 (d, J = 9 Hz), 131.68 (d, J =
3 Hz), 132.53 (d, J = 98 Hz) ppm. 31P NMR (160 MHz,
CDCl3): d = 32.52 ppm. MS (ESI/TOF): m/z = 445 [M + H]+.
HRMS: m/z calcd for C27H26O2NaP2: 467.1306; found:
467.1312.
Compound 4b: yellow oil. 1H NMR (400 MHz, CDCl3): d =
1.23 (t, J = 7.2 Hz, 6 H), 1.81–1.95 (m, 4 H), 2.38–2.43 (m,
2 H), 3.98–4.03 (m, 4 H), 7.43–7.51 (m, 6 H), 7.69–7.75 (m,
4 H) ppm. 13C NMR (100 MHz, CDCl3): d = 15.29, 16.33 (d,
6 H), 26.26 (dd, J = 14, 140 Hz), 30.00 (d, J = 84 Hz),
128.62 (d, J = 11 Hz), 130.68 (d, J = 10 Hz), 131.73 (d, J =
2 Hz), 132.61 (d, J = 98 Hz) ppm. 31P NMR (160 MHz,
CDCl3): d = 30.58, 32.01 ppm. MS (ESI/TOF): m/z = 381
[M + H]+. HRMS: m/z calcd for C19H26O4NaP2: 403.1204;
found: 403.1211.
Compound 1a: white solid, mp 89–90 °C. 1H NMR (400
MHz, CDCl3): d = 2.11 (d, J = 3.6 Hz, 3 H), 7.43–7.48 (m, 6
H), 7.79–7.85 (m, 4 H) ppm. 13C NMR (100 MHz, CDCl3):
d = 5.02 (d, J = 3 Hz), 75.33 (d, J = 174 Hz), 105.46 (d,
J = 32 Hz), 128.44 (t, J = 10 Hz), 130.81 (d, J = 12 Hz),
132.01 (d, J = 3 Hz), 133.20 (d, J = 121 Hz) ppm. 31P NMR
(160 MHz, CDCl3): d = 7.76 ppm. MS (ESI/TOF): m/z = 241
[M + H]+.
Compound 1b: white solid, mp 67–68 °C. 1H NMR (400
MHz, CDCl3): d = 1.86 (d, J = 14.4 Hz, 3 H), 2.04 (d, J = 3.6
Hz, 3H), 7.47-7.56 (m, 3H), 7.81-7.87 (m, 2H).13C NMR
(100 MHz, CDCl3): d = 4.77 (d, J = 3 Hz), 20.53 (d, J = 86
Hz), 75.22 (d, J = 167 Hz), 103.2 (d, J = 32 Hz), 128.56 (d,
J = 13 Hz), 129.85 (d, J = 11 Hz), 131.99 (d, J = 3 Hz),
133.54 (d, J = 118 Hz) ppm. 31P NMR (160 MHz, CDCl3) d
= 10.17 ppm. MS (ESI/TOF): m/z = 179 [M + H]+.
Compound 1c: white solid, mp 93–94 °C. 1H NMR (400
MHz, CDCl3): d = 2.12 (d, J = 4 Hz, 3 H), 7.41–7.48 (m, 6
H), 7.89–7.92 (m, 4 H) ppm. 13C NMR (100 MHz, CDCl3):
d = 5.39 (d, J = 3 Hz), 73.25 (d, J = 158 Hz), 106.07 (d,
J = 28 Hz), 128.52 (d, J = 14 Hz), 130.73 (d, J = 12 Hz),
131.66 (d, J = 3 Hz), 133.83 (d, J = 97 Hz) ppm. 31P NMR
(160 MHz, CDCl3): d = 19.69 ppm. MS (ESI/TOF): m/z =
257 [M + H]+.
Compound 4c: yellow oil. 1H NMR (400 MHz, CDCl3): d =
1.18–1.24 (m, 3 H), 1.75–2.08 (m, 4 H), 2.35–2.46 (m, 2H);
3.74–3.80 (m, 1 H), 3.95–4.02 (m, 1 H), 7.39–7.51 (m, 9 H),
7.63–7.72 (m, 6 H) ppm. 13C NMR (100 MHz, CDCl3): d =
14.63, 16.35 (d, J = 6 Hz), 30.15 (dd, J = 14, 100 Hz), 60.51
(d, J = 6 Hz), 128.58 (d, J = 12 Hz), 130.67 (d, J = 9 Hz),
131.50 (d, J = 10 Hz), 131.68 (s, l), 132.22–132.27 (m)ppm.
31P NMR (160 MHz, CDCl3): d = 32.17, 43.68 ppm. MS
(ESI/TOF): m/z = 413 [M + H]+. HRMS: m/z calcd for
C23H26O3NaP2: 435.1255; found: 435.1258.
Compound 4d: white solid, mp 145–148 °C. 1H NMR (400
MHz, CDCl3): d = 1.37 (d, J = 12.0 Hz, 6 H), 1.85–1.94 (m,
4 H), 2,37–4,48 (m, 2 H), 7.40–7.47 (m, 6 H), 7.69 (t, J = 8.8
Hz, 4 H) ppm. 13C NMR (100 MHz, CDCl3): d = 14.85,
16.03 (d, J = 68 Hz), 22.12, 30.24 (dd, J = 12, 71 Hz),
31.77–31.83 (m), 32.43 (d, J = 13 Hz), 128.68 (d, J = 12
Hz), 130.62 (d, J = 9 Hz), 131.84 (d, J = 2 Hz), 132.83 ppm.
31P NMR (160 MHz, CDCl3): d = 32.45, 43.33 ppm. MS
(ESI/TOF): m/z = 321 [M + H]+. HRMS: m/z calcd for
C17H22O2NaP2: 343.0993; found: 343.0995.
Compound 1d: white solid, mp 85–86 °C. 1H NMR (400
MHz, CDCl3): d = 1.88 (d, J = 4.0 Hz, 6 H), 7.31–7.41 (m, 3
H), 7.77 (dd, J = 7.2, 15.6 Hz) ppm. 13C NMR (100 MHz,
CDCl3): d = 4.76 (d, J = 4 Hz), 74.85 (d, J = 102 Hz), 103.42
(d, J = 39 Hz), 128.47 (d, J = 15 Hz), 129.92 (d, J = 12 Hz),
132.35 (d, J = 3 Hz), 132.97 (d, J = 141 Hz) ppm. 31P NMR
Synlett 2009, No. 9, 1466–1470 © Thieme Stuttgart · New York

1470
Y. Lin et al.
LETTER
Compound 4e: yellow oil. 1H NMR (400 MHz, CDCl3): d =
1.05–1.17 (m, 6 H), 1.58 (d, J = 11.2 Hz, 3 H), 1.65–1.96 (m,
6 H), 3.85–3.92 (m, 4 H), 7.35–7.40 (m, 3 H), 7.58 (s, l, 2 H)
ppm. 13C NMR (100 MHz, CDCl3): d = 15.29 (d, J = 4 Hz),
16.17 (d, J = 70 Hz), 16.27 (t, J = 5 Hz), 26.24 (dd, J = 13,
140 Hz), 31.55–32.69 (m), 61.39 (d, J = 6.4 Hz), 128.58 (d,
J = 10 Hz), 128.58 (d, J = 11 Hz), 129.90 (d, J = 8 Hz),
131.62, 133.05 (d, J = 97 Hz)ppm. 31P NMR (160 MHz,
CDCl3): d = 30.42, 36.84 ppm. MS (ESI/TOF): m/z = 319 [M
+ H]+. HRMS: m/z calcd for C14H24O4NaP2: 341.1048;
found: 341.1046.
for C18H24O3NaP2: 373.1098; found: 373.1097.
Compound 4g: dark oil. 1H NMR (400 MHz, CDCl3): d =
1.08–1.49 (m, 8 H), 1.71–2.09 (m, 4 H), 3.88–4.16 (m, 4 H),
7.28–7.60 (m, 6 H), 7.63–8.87 (m, 3 H) ppm. 13C NMR (100
MHz, CDCl3): d = 0.98, 16.38 (d, J = 5 Hz), 19.68, 22.64,
29.30, 29.40, 29.64, 31.86, 61.59 (d, J = 6 Hz), 128.40,
128.55, 128.67, 130.45, 131.00 (d, J = 11 Hz), 131.50,
131.87 (d, J = 11 Hz), 133.67 ppm. 31P NMR (160 MHz,
CDCl3): d = 30.66, 42.12 ppm. MS (ESI/TOF): m/z = 397
[M + H]+. HRMS: m/z calcd for C19H26O3NaP2S: 419.0976;
found: 419.0981.
Compound 4f: colorless oil. 1H NMR (400 MHz, CDCl3):
d = 1.03–1.17 (m, 3 H), 1.53 (t, J = 12.8 Hz, 3 H), 1.58–1.98
(m, 6 H), 3.61–3.71 (m, 1 H), 3.83–3.93 (m, 1 H), 7.26–7.42
(m, 6 H), 7.48–7.62 (m, 4 H) ppm. 13C NMR (100 MHz,
CDCl3): d = 14.53–14.65 (m), 15.54, 15.76, 16.22–16.46
(m), 29.67 (t, J = 14 Hz), 30.67 (t, J = 14 Hz), 31.70 (t,
J = 12 Hz), 32.39 (t, J = 12 Hz), 57.46, 60.34–60.45 (m),
128.42–128.62 (m), 129.57 (d, J = 20 Hz), 129.83 (d, J = 9
Hz), 130.79 (d, J = 20 Hz), 131.38 (d, J = 10 Hz), 131.51–
131.61 (m), 132.16–132.35 (m), 132.44 (d, J = 20 Hz),
133.39 (d, J = 20 Hz)ppm. 31P NMR (160 MHz, CDCl3): d =
36.74 (d, J = 3.4 Hz), 36.85, 43.27 (d, J = 3.5 Hz), 43.44
ppm. MS (ESI/TOF): m/z = 351 [M + H]+. HRMS: m/z calcd
Compound 4h: colorless oil. 1H NMR (400 MHz, CDCl3):
d = 1.23 (t, J = 6.8 Hz, 6 H), 1.28 (t, J = 6.8 Hz, 6 H), 1.72–
1.96 (m, 12 H), 3.96–4.10 (m, 8 H), 7.47–7.54 (m, 3 H),
7.67–7.72 (m, 2 H). 13C NMR (100 MHz, CDCl3): d = 15.14
(t, J = 4 Hz), 16.34 (t, J = 6 Hz), 26.34 (dd, J = 14, 140 Hz),
30.37 (dd, J = 14, 68 Hz), 61.52 (d, J = 6 Hz), 128.76 (d,
J = 11 Hz), 130.41 (d, J = 9 Hz), 131.28 (d, J = 92 Hz),
131.82 (d, J = 3 Hz) ppm. 31P NMR (160 MHz, CDCl3): d =
30.45, 30.48, 39.71 ppm. MS (ESI/TOF): m/z = 483 [M +
H]+. HRMS: m/z calcd for C20H37O7NaP3: 505.1650; found:
505.1645.
(10) Benn, R. F.; Briggs, J. C.; McAuliffe, C. A. J. Chem. Soc.,
Dalton Trans. 1984, 293.
Synlett 2009, No. 9, 1466–1470 © Thieme Stuttgart · New York

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