Catalytic hydrophosphination of styrenes

Article abstract of DOI:10.1021/ol017238s

(equation presented) The first example of intermolecular hydrophosphination of styrenes catalyzed by Ni and Pd complexes is described. The reaction of Ph₂PH with styrene, 4-vinylpyridine, 2-vinylpyridine, 4-methoxystyrene, 2-methoxystyrene, and 5-vinyl-2-methylpyridine in benzene under Ni[P(OEt)₃]₄ catalysis proceeds with high yield and selectivity to give only anti-Markovnikov product.

Full text of DOI:10.1021/ol017238s

ORGANIC
LETTERS
2
002
Vol. 4, No. 5
61-763
Catalytic Hydrophosphination of
Styrenes
7
Mstislav O. Shulyupin, Marina A. Kazankova, and Irina P. Beletskaya*
Department of Chemistry, Moscow State UniVersity, Leninskie Gory,
GSP-3 Moscow, Russian Federation
beletska@org.chem.msu.ru
Received December 17, 2001
ABSTRACT
The first example of intermolecular hydrophosphination of styrenes catalyzed by Ni and Pd complexes is described. The reaction of Ph
with styrene, 4-vinylpyridine, 2-vinylpyridine, 4-methoxystyrene, 2-methoxystyrene, and 5-vinyl-2-methylpyridine in benzene under Ni[P(OEt)
catalysis proceeds with high yield and selectivity to give only anti-Markovnikov product.
2
PH
3 4
]
Tertiary phosphines are an important class of organic
compounds widely employed both as ligands for transition
metals complexes and in various catalytic processes. Though
addition of P-H reagents to olefins. This reaction can be
carried out in the presence of radical initiators, in the acid-
1
5
or base-catalyzed process, or in the presence of transition
6
in common applications triarylphosphines are usually used,
the more electron-rich alkyldiarylphosphines may bring
special advantages in more demanding cases.2 The ligands
metal catalysts and lanthanides.
Here, we report the first example of the addition of
secondary phosphine across the double bond of aryl (het-
eroaryl)ethenes catalyzed by Ni and Pd complexes. Recently,
it was shown that diphenylphosphine addition across an
unactivated triple bond is catalyzed by these complexes.7
,3
2 2
Ph PAlk are obtained by coupling Ph PHal with organo-
lithium or magnesium compounds or by the reaction between
4
phosphide anion and an alkylhalide. However, from the
point of view of “green chemistry” and the “atom efficiency”
principle, the cleanest route toward such phosphines is the
(
5) Wolfsberger, W. Chem. Zeitung 1988, 112, 53.
(6) Pt- and Pd-catalyzed addition of Ph2PH and PH3 to a double bond is
limited to Michael-type activated alkenes: Nagel, U.; Reigel, B.; Bublewitz,
A. J. Organomet. Chem. 1989, 370, 223. Hoye, P. A. T.; Pringle, P. G.;
Smith, M. B. J. Chem. Soc., Chem. Commun. 1990, 1701. Pringle, P. G.;
Brewin, D.; Smith, M. B.; Worboys, K. In Aqueous Organometallic
Chemistry and Catalysis; Horvath, I. T., Joo, F., Eds.; Dordrecht, The
Netherlands, 1995; Vol. 5, p 111. Costa, E.; Pringle, P. G.; Smith, M. B.;
Worboys, K. J. Chem. Soc., Dalton Trans. 1997, 4277. Wicht, D. K.;
Kourkine, I. V.; Lew, B. M.; Nthenge, J. M.; Glueck, D. S. J. Am. Chem.
Soc. 1997, 119, 5039. Costa, E.; Pringle, P. G.; Worboys, K. Chem.
Commun. 1998, 49. Orpen, A. G.; Pringle, P. G.; Smith, M. B.; Worboys,
K. J. Organomet. Chem. 1998, 550, 255. Wicht, D. K.; Kourkine, I. V.;
Kovacik, I.; Glueck, D. S.; Concolino, T. E.; Yap, G. P. A.; Incarvito, C.
D.; Rheingold, A. L. Organometallics 1999, 18, 5381. Wicht, D. K.;
Kovacik, I.; Glueck, D. S. Liable-Sands, L. M.; Incarvito, C. D.; Rheingold,
A. L. Organometallics 1999, 18, 5141. Kovacik, I.; Wicht, D. K.; Grewal,
N. S.; Glueck, D. S.; Incarvito, C. D.; Guzei, I. A.; Rheingold, A. L.
Organometallics 2000, 19, 950. Hydrophosphination of an unactivated
double bond by lanthanide catalysis: Douglass, M. R.; Marks. T. J. J. Am.
Chem. Soc. 2000, 122, 1824. Takaki, K.; Takeda, M.; Koshoji, G.; Shishido,
T.; Takehira, K. Tetrahedron Lett. 2001, 42, 6357. Douglass, M. R.; Stern,
C. L.; Marks, T. J. J. Am. Chem. Soc. 2001, 123, 10221.
(
1) Collman, J. P.; Hegedus, L. S.; Norton, J. R.; Finke, R. G. Principles
and Applications of Organotransition Metal Chemistry; University Science
Books: Mill Valley, CA, 1987. Omac, J. Application of Organometallic
Compounds; Wiley: Toronto, 1999. ComprehensiVe Organometallic Chem-
istry, 2nd ed.; Abel, E. N., Jordon, F., Stone, A., Wilkinson, J., Eds.;
Pergamon Press: New York, 1995; Vola. 9 and 12. Brandsma, L.;
Vasilevsky, S. F.; Verkruijsse, H. D. Application of Transition Metal
Catalysts in Organic Synthesis; Springer-Verlag: Berlin, Heidelberg, New
York, 1999.
(2) Applied Homogeneous Catalysis with Organometallic Compounds;
Cornils, B.; Herrmann, W. A., Eds.; VCH: New York, 1996. Homogeneous
Catalysis with Metal-Phosphine Complexes; Pignolet, L. H., Ed.; Plenum
Press: New York, 1983.
(3) Han, L.-B.; Mizaeri. F.; Zhao Ch.-Q.; Tanaka, M. J. Am. Chem. Soc.
2
1
000, 122, 5407. Han, L.-B.; Tanaka, M. J. Am. Chem. Soc. 1996, 118,
571.
(4) For example, see: The Chemistry of Functional GroupssThe
Chemistry of Organophosphorus Compounds; Hartley, F. R., Ed.; Wiley:
Chichester, U.K., 1990-1992. Handbook of Organophosphorus Chemistry;
Engel, R., Ed.; Marcel Dehker: New York, 1992.
1
0.1021/ol017238s CCC: $22.00 © 2002 American Chemical Society
Published on Web 02/09/2002

We screened numerous readily available nickel and
palladium complexes (NiCl , NiBr , Ni(PPh Cl , Ni(PPh
Br , Ni(acac) , Ni(cod) , Ni[P(OEt) , Pd(CH CN) Cl ) and
found that Ni(II) complexes catalyze the oxidative dimer-
ization of Ph PH to form tetraphenyldiphosphine, whereas
(Table 1, entry 6). Thus we have found that heating a mixture
of 2 equiv of styrene, 1 equiv of diphenylphosphine, and 1
2
2
)
3 2
2
3 2
) -
2
2
2
]
3 4
3
2
2
equiv of Et
in benzene in a sealed tube at 130 °C for 20 h provided the
desired Ph PCH CH Ph in quantitative yield.
3
N with 5 mol % tetrakis(triethyl phosphite)nickel
2
2
2
2
with the Ni(0) complexes the reaction of hydrophosphination
of styrene takes place.
A possible mechanism of hydrophosphination is presented
in Scheme 2. To test the scope of the reaction several styrenes
were employed under optimal conditions (Table 2).
Scheme 1
Scheme 2
The catalytic system has a dramatic influence on the
structure of the products of the reaction. The use of
Ni(PPh ) Br results in a fast oxidative reaction (Table 1,
3 2 2
Table 1. Hydrophosphination of Styrene Catalyzed by Pd and
Ni Complexes in Benzenea
ratio of
1
:2 (%)b
entry
catalyst, 5%
temp °C/h conversionb
1
2
So we have designed a new catalytic system for the
hydrophosphination of styrenes.
1
2
3
4
5
6
7
Ni(PPh3)2Br2
Ni(PPh3)2Br2
Ni[P(OEt)3]4
Ni[P(OEt)3]4
Ni[P(OEt)3]4
Ni[P(OEt)3]4
Pd(CH3CN)2Cl2
50/5
130/28
90/40
100
100c
85
0
100
50
5
10
0
11
50
95
90
100
100
100
130/40
130/40
130/20
90/40
95
95c
100c,d
75
2 2
Table 2. Hydrophosphination of ArCHdCH with Ph PH
0
0
a
3 4
Catalyzed by Ni[P(OEt) ]
a
Reaction conditions: styrene 1.5 mmol, Ph2PH 1.5 mmol, catalyst 5%
mol, benzene 2 mL, sealed tube. Based on P and H NMR. c One
equivvalent of Et3N was added. Two equivalents of styrene was used.
b
31
1
d
8
entry 1) leading to tetraphenyldiphosphine. We suppose that
diphen-
ylphosphine is oxidized by Ni(II) to form Ph
The latter carries on the catalytic cycle, reacting with Ni(0)
to regenerate Ni(II) again. That is why the addition of Et
to neutralize HBr suppresses the oxidation of phosphine
Table 1, entry 2). When the Ni(0) complex was used instead
of Ni(II) complex, only small amounts of Ph PPPh were
formed (Table 1, entry 3), but when the temperature was
raised, the amount of Ph PPPh increased (Table 1, entry
). The addition of Et N completely suppressed the side
2 2
PPPh and HBr.
3
N
(
2
2
2
2
4
3
reaction (Table 1, entry 5). The acceleration of the addition
reaction was observed when an excess of styrene was added
(
7) Kazankova, M. A.; Efimova, I. V.; Kochetkov, A. N.; Afanas’ev, V.
V.; Beletskaya I. P.; Dixneuf, P. H. Synlett 2001, 497.
8) The catalytic reaction of oxidation of Ph2PH to Ph2PPPh2 can be
a
(
Reaction conditions: 5 mol % Ni[P(OEt)3]4, benzene, 2 equiv of
styrene, 1 equiv of Et3N 130 °C, 20 h. b Based on P NMR.
31
developed to a useful synthetic method. See also: Tunney, S. E.; Stille J.
K. J. Org. Chem. 1987, 748.
762
Org. Lett., Vol. 4, No. 5, 2002

Acknowledgment. The authors are grateful to INTAS
97-1874), RFBR (N 00-03-32747 and N 00-15-97406)
programmers for financial support.
Supporting Information Available: Experimental pro-
cedures and compound characterization data. This material
is available free of charge via the Internet at http://pubs.acs.org.
(
(
9) Khachatryan, R. A.; Sayadyan, S. V.; Grigoryan, N. Yu.; Indzhikyan,
OL017238S
M. G. J. Gen. Chem. USSR (Engl. Transl.) 1988, 58, 2197. Issleib, K.;
Jasche, K Chem. Ber. 1967, 100, 412.
(
10) Wang, H.-H.; Casalnuovo, A. L.; Johnson, B. J.; Huetig, A. M.;
3.43 (s, 3H), 6.79-6.86 (m, 4H), 7.15-7.21 (m, 6H), 7.50-7.54 (m, 4H);
31
Pignolet, L. H. Inorg. Chem. 1988, 27, 325. Uhlig, V. E,; Maaser, M. Z. Z.
Anorg. Allg. Chem. 1966, 344, 205.
P{H} NMR (162.6 MHz, C6D6) -16.3 (s). [2-(2-Methoxyphenyl)ehyl]-
(diphenyl)phosphine (4): IH NMR (400 MHz, C6D6) 2.45-2.49 (m, 2H),
2.97-3.03 (m, 2H), 3.36 (s, 3H), 6.61 (d, 1H), 6.91 (t, 1H), 7.08-7.20 (m,
(11) General Procedure. A mixture of 1.5 mmol of Ph2PH, 3 mmol of
31
alkene, 1.5 mmol of Et3N, and 5 mol % of Ni[P(OEt)3]4 in 2 mL of the
benzene was placed in an NMR tube and sealed. The tube was heated in
an oil bath at 130 °C, and the reaction was followed using 31P NMR
measurements. After completion of the reaction (disappearance of the signal
of Ph2PH at δp -40.6 ppm) the solvents were evaporated in a vacuum.
The residue was recrystallized from a hexane/THF mixture and purified by
column chromatography (hexane/benzene 3:1). Diphenyl(2-phenylethyl)-
phosphine (1): IH NMR (400 MHz, C6D6) 2.31-2.36 (m, 2H), 2.74-2.80
8H), 7.54-7.58 (m, 4H); P{H} NMR (162.6 MHz, C6D6) -15.6 (s). 4-[2-
I
(Diphenylphosphino)ethyl]pyridine (5): H NMR (400 MHz, C6D6) 2.65-
2.69 (m, 2H), 2.99-3.05 (m, 2H), 6.69-6.71 (m, 2H), 7.09-7.18 (m, 6H),
31
7.53-7.57 (m, 4H), 8.56-8.58 (m, 2H); P{H} NMR (162.6 MHz, C6D6)
-16.1 (s). 5-[2-(Diphenylphosphino)ethyl]-2-methylpyridine (6): NMR (400
MHz, C6D6) 2.27-2.31 (m, 2H), 2.46 (s, 3H), 2.60-2.67 (m, 2H), 6.97-
3
1
7.01 (m, 2H), 7.25-7.35 (m, 6H), 7.39-7.45 (m. 4H), 8.27 (s, 1H); P-
{H} NMR (162.6 MHz, C6D6) -16.5 (s). 2-[2-(Diphenylphosphino)ethyl]-
pyridine (7): IH NMR (400 MHz, C6D6) 2.65-2.69 (m, 2H), 2.99-3.05
(m, 2H), 6.68-6.71 (m, 2H), 7.06-7.14 (m, 7H), 7.53-7.57 (m, 4H), 8.56-
3
1
(
m, 2H), 7.06-7.21 (m, 11H), 7.48-7.52 (m, 4H); P{H} NMR (162.6
MHz, C6D6) -16.1 (s). [2-(4-Methoxyphenyl)ehyl](diphenyl)phosphine
3): IH NMR (400 MHz, C6D6) 2.33-2.37 (m, 2H), 2.74-2.80 (m, 2H),
31
(
8.58 (m, 1H); P{H} NMR (162.6 MHz, C6D6) -15.8 (s).
Org. Lett., Vol. 4, No. 5, 2002
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