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Nucleophilic Substitution of Hydrogen in Nitroarenes by Phosphorus-Stabilized Carbanions having УVicariousФ Leaving Groups.

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Chem. 1980.512: U. Heimann, F.Vogtle, Chem. Ber. 112 (1979) 3034; F.
Viigtle, G. Oepen, W. Rasshofer, Liebigs Ann. Chem. 1979, 1577.
[5] Neutron diffraction: J. E. Worsham, W. R. Busing, Acta Crn!ai/ogr. B
25 (1969) 572; X-ray diffraction: S. Harkema, D. Feil, ibid. B 25 (1969)
589.
[ I I] J. W. H. M. Uiterwijk, S. Harkema, G. 1. van Hummel, J. Geevers, D. N.
Reinhoudt, Acfa Crysfdlogr.B. in press.
[16] J. W. H. M. Uiterwijk, S. Harkema, J. Geevers, D. N. Reinhoudt, J.
Chem. SOC.Chem. Commun. 1982, 200.
4
I
Nucleophilic Substitution of Hydrogen in
Nitroarenes by Phosphorus-Stabilized Carbanions
having "Vicarious" Leaving Groups
By Mieczysiaw Mgkosza, Jerzy Golinski
We have previously described the vicarious nucleophilic
substitution of hydrogen in nitroarenes by carbanions containing leaving groups at the carbanionic center"'. This
principle is shown in Scheme 1.
Y
I
CH-R'
Fig. I. Top and side views of the [18]crown-6.uronium nitrate (111) complqx
in the crystal. P2,/n, a=20.304(9), b=11.604(6), c=8.181(3) A,
8=93.95(4)".
I
I
NO2
a g + a g + g + a ag-a ag-a), the positions of the crown oxygens used in hydrogen bonding are quite the same relative
to the central cation.
NO2
Scheme 1. Y = stabilizing group, X = leaving group [I].
We have now found that stabilization by phosphoruscontaining groups offers particular advantages. As model
compounds dimethyl a-chlorobenzylphosphonate 1 and
chloromethyl(dipheny1)phosphane oxide 2 were selected.
1 reacts with nitrobenzene in dimethylformamide in
presence of sodium hydride to give dimethyl 4-nitrobenzhydrylphosphonate 4a in 39% yield. In contrast, a 78%
yield was obtained when the reaction was carried out in liquid ammonia in presence of powdered sodium hydroxide. For the reactions with 2, potassium hydroxide in
dimethyl sulfoxide (DMSO) was the most efficient system.
G
3
Ph P-0
21-
CH2
Fig. 2. Top and side views of the benzo[27]crown-9~uroniumperchlorate (I./
I) complex in the crystal. Pi, u = 13.866(5), b = 12.585(7), c=9.926(6) A,
a =99.59(3), 8=74.91(6), y = 116.52(3)".
The results presented here show that crown ethers in
complexes with polyfunctional organic cations can assume
various conformations depending upon the type of cation
and anion.
Received: February 24, 1982 [ Z 119 IE]
German version: Angew. Chem. 94 (1982) 462
The complete manuscript of this communication appears in:
Angew. Chem. Suppl. 1982, 1100-1107
4
Q
R2
Q
NO2
R2
5
NO2
Table 1 shows examples. From these results it should be
noted that the carbanions generated from 1 and 2 react
with 0- and p-chloronitrobenzenes exclusively at unsubstituted positions. No appreciable replacement of chlorine is
observed, although it is strongly activated toward nucleophilic substitution by the nitro group. This is strong evi*I Prof. Dr. M. Mgkosza, Dr. J. Golinski
[I1 S . Harkema, G.J. van Hummel, K. Daasvatn, D. N. Reinhoudt, J. Chem.
SOC.Chem. Commun. 1981. 368.
[2] For complexes of urea and linear polyethers, see: W. Rasshofer and F.
Vogtle, Tetrahedron Lert. 1978. 309; G. Oepen, F. Vogtle, Liebigs Ann.
Angew. Chem. Int. Ed. Engl. 21 (19821 NO.6
Institute of Organic Chemistry Polish Academy of Sciences
PL-01-244 Warszawa, Kasprzaka 44/52 (Poland)
[**I T h i s work was supported by the Polish Academy of Sciences (MR.4.
12.1.1). Fluka AG is thanked for a gift of chloro(dipheny1)phosphane.
0 Veriag Chemie GmbH. 6940 Weinheim. 1982
0570-0833/82/0606-0451 S 02.50/0
45 1
Table 1. Nucleophilic substitution of hydrogen in the nitroarenes 3 with the
phosphorus compounds 1 (method A ) [3] and 2 (method B) 141 as precursors
of carbanions [a, b].
Reagent
Product
Rz
1
1
1
4a
4b
4c
H
0-CI
m-CI
1
46
[Q
2
2
5a
p-CI
p-Br
5b
M.p. PC] (Solvent) 'H-NMR [c]
6
J(H-P)
99.5-101 (MeOH) 4.6
72-73 [el
4.5
5.1
78-79[e]
152-1533 (EtOH) 5.4
188--189.5(EtOH) 4.2
195--197.5(EtOH) 4.2
[Hz]
26
12
25
27
18
17
Yield
[Yo] [d]
78
62
65
31
41
52
[a] Method A : A mixture of 1 131 (0.01 mol) and the nitroarene (0.01 mol)
in ethyl ether ( I 5 mL) was added dropwise to a stirred suspension of powdered
NaOH (4 g, 0.1 mol) in liquid NH, (20 ml) at -30°C. After I h the mixture
was poured into a beaker, and after evaporation of NH, the residue was
treated with water (100 mL), acidified, and extracted with benzene. The combined extracts were dried, the solvent evaporated, and the residue recrystallized.-Method B: Potassium hydroxide (4 g, 0.075 mol) was suspended in
DMSO (15 mL) and to this stirred mixture (<25"C) a solution of 2 [4j (2.5 g,
0.01 mol) and 3 (0.01 mol) in DMSO (5 mL) was added dropwise. After 1 h
the mixture was diluted with water (150 mL), acidified and extracted with
benzene and treated further as in method A. [b] All new compounds gave
correct analyses and satisfactory IR and NMR spectra. [c] In CDC13; C H or
CH2. [d] Not optimized. [el Solvent benzenelhexane. [fl Educt: l-nitronaphthalene; product: dimethyl-u-(4-nitro- 1-naphthyl)benzylphosphate4d.
plexes of palladium(1l) and platinum(i1). In this preliminary communication we now wish to report our attempts
to synthesize related complexes of rhodium and iridium[21.
Thus, treatment of [{IrCl(cod)],] (cod = cycloocta- 1,5diene) with an excess of Ph2PCl in aqueous methanol
(1 :7; v/v) at ambient temperature [i. e. Ph2P(0)H + HCI
mixture] gave as the major product, the neutral, monomeric iridium(rrr) complex 1. In solution, 1 readily loses
diene and therefore on treatment with bidentate ligands L2
forms compounds 2a-c in high yields, which shorw no
tendency to undergo further ligand dissociation. Reaction
of 2b with HBF4 gave the cationic complex 3b, which
readily rearranged to 4b when redissolved in CHC13. 4b
can also be synthesized by reaction of 2b with BF3. Et20.
Preliminary studies indicate that reaction of 1 with the
platinum species 5 leads to formation of the unusual
mixed metal complex 6[41.The synthesis of a range of such
mixed metal complexes is now in progress.
/
a
dence that the p- o r o-hydrogen of nitroarenes is attacked
at a much higher rate than those positions which are substituted with good leaving groups. - The process described
allows the preparation of a variety of organophosphorus
compounds with nitroaryl groups, which could be of significant value in organic synthesis'21.
Received: November 9, 1981 [Z 117 IE]
German version: Angew. Chem. 94 (1982) 468
[I] J. Golinski, M. Mgkosza, Tetrahedron Lett. 1978, 3495; M. Mgkosza, J.
Winiarski, J. Org. Chem. 45 (1980) 1534.
[2] J. 1. G. Cadogan: Organophosphorus Reagents in Organic Synthesis, Aca-
NEtzH,
demic Press, London 1979.
[3] M. 1. Kabachnik, E. S. Shepeleva, Izu. Akad. Nauk SSSR Old. Khim.
Nauk 1950, 39; Chem. Abstr. 44 (1950) 1257.
[4] M. 1. Kabachnik, T. Ya. Medved, Yu. M. Polikarpov, K. S. Yudina, Izu.
Akad. Nauk SSSR. Ser. Khim. 1967, 591.
Synthesis of Novel Iridium and Rhodium Complexes
Containing Diphenylphosphinito and
Dimethylphosphito Ligands**
By J. Andrew S. Duncan, David Hedden,
D. Max Roundhill, T. Anthony Stephenson*,
and Malcolm D . Walkinshaw
In recent years, a number of transition metal compounds
containing the hydrogen-bonded R2POHOPR2 ligands
( R = Ph, OMe, OEt) have been synthesized and some reactions of these compounds reported"]. To date, however,
the majority of these studies have been confined to com[*] Dr. T. A. Stephenson, Dr. M. D. Walkinshaw, J. A. S. Duncan
[**I
Department of Chemistry, University of Edinburgh
West Mains Road, Edinburgh EH9 3JJ (Scotland)
Prof. D. M. Roundhill, D. Hedden
Department of Chemistry, Washington State University
Pullman, Washington (USA)
We thank the Science and Engineering Research Council for a research
studentship (to J.A.S.D), the Petroleum Research Fund (Grant No.
1 1633AC 3) and NATO (Grant No. 1725) for financial support and
Johnson-Matthey Ltd. (T.A.S.) and Engelhard (D.M.R) for generous
loans of rhodium and indium trichlorides.
452
0 Verlag Chemie GmbH. 6940 Weinheirn. 1982
a, L,
C,
= Ph,P(CH2)2PPh,; b, L, = Ph,As(CH,),AsPh,;
L2 = PhS(CH2)zSPh
-
8
Similarly, treatment of the iridium complex 7 with
(MeO),P(O)H gave an almost quantitative yield of the
closely related cationic complex 8, whose configuration
was determined 'H-NMR spectroscopically.
In contrast, related (diene)-rhodium(1) compounds react
with various R,P(O)H ligands, undergoing facile diene displacement to generate quite different species. Furthermore, the nature of the product from the reaction of
[(RhCl(cod)),] with an excess of PhzPCl in aqueous methanol depended critically on the water to methanol ratio. At
low water :methanol ratios (I : 15, v/v) the only products
formed were the well-known cations [Rh(Ph,POMe),]+
0570-0833/82/~606-0452S 0.?.50/0
Angew. Chem. InJ. Ed. Engl. 21 (1982) No. 6
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