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New Process for the Sulfonation of Phosphane Ligands for Catalysts.

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a little cold hexane to give [D,]-I (1.07 g. 3.1 mmol, 81 O h ) . "{'Hi N M R (C,H,):
6 = 4.2 (br, full width at half maximum = 6 Hz).
General hydrobordtion procedure: To a suspension of HB(C,F,), (0.1 mmol) in dry
benzene (0.6 mL) under an argon atmosphere was added the dried alkene or alkyne
substrate (1 equtv) hy syringe. The mixture was sonicated for 30-60s and then
shaken. The reaction progress was monitored by ' H N M R spectroscopy.
Received: October 11, 1994 [Z7393IE]
German version: Angew Chem. 1995, 107, 895
Keywords: boranes . hydroborations
[I] a) H. C. Brown, Hydrohorution, Benjamin. New York, 1962; b) A. Pelter, K.
Smith, H. C. Brown, Borune Reagents, Academic Press, London, 1988; c) K .
Smith. A. Pelter in Coniprehensive Organic SwtheAis, Vol. 8 (Eds.: B. M. Trost,
1. Fleming). Pergamon. New York, 1991, p. 703.
[2] R . D. Chambers. T. Chivers, J. Chem. Sot.. 1965, 3933.
[3] K. Smith, A. Pelter, Z. Jin, Angew. Chem. 1994, 106, 913; Angew. Chem. Inf.
Ed Engl. 1994, 33. 851.
[4] K. Ishihara. N. Hananki, H. Ydmamoto, Synlett 1993. 577.
[S] T H E for example, could not be removed, and a t elevated temperatures (80 'C)
1 was observed to react with T H F to yield (C,F,),BO(CH,),CH,.
[6] G. Socrdtes, Infrurrd Cliuracteristic Group Frequencies, Wiley. New York.
1980, p. 130.
[7] A. Pelter, K . Smith, D. Buss, A. Norbury, Rtruhedron Left. 1991, 32, 6239.
[XI E. Negishi. JLJ. Katz, H. C. Brown. J Am. Chem. Soc. 1972, 94, 4025.
[9] J. A. Soderquist, H. C. Brown, J Org. Chem. 1980, 45, 3571.
[lo] The reactions were all quantitative by NMR, and the products were characterized by ' H and "C N M R spectroscopy or by further derivitization of the
alkylborane products.
[ l l ] H. C. Brown. R. Liotta, C . G . Scouten. J. A m . Chern. Sor. 1976. 98, 5297.
[12] Although relative rates of hydroboration for these two substrates may still be
quite different, in practical terms the rate difference is not important owing to
the high activity of 1.
[13] H . C. Brown. C. G. Scouten, R. Liaotta. J. Am. Chem. Sot.. 1979, 101. 96.
[14] H. C. Brown, B. C. Subba Rao, J. Am. Chem. Soc. 1959.81.6428.
[15] E. Negishi, H. C. Brown. Synthesis 1980, 153.
[lh] L. D. Field, S . P. Gallagher, Tetrahedron Lett. 1985, 26, 6125.
[17] a) J. A. Soderquist. J. C. Colberg, L. Del Valle. J Am. Chem. Sac. 1989, 1 1 1 ,
4873; b) M. Hoshi. Y. Masnda. A. Ardse, J. Chem. Sor. Perkin Truns. I 1990,
3237.
[I81 J. B. Lambert. Tefraliedron 1990, 46, 2677.
[19] J. A. Soderquist, M. R. Najafi, J. Org. Chem. 1986, 5f,1330.
[20] L. Jia. X. Ydng, C. Stern, T. J. Marks, Orgunometullrcs 1994. 13. 3755.
sulfonation of the aryl groups it also causes the formation of
undesirable phosphane oxides, which, according to our present
understanding, are useless for catalytic purposes and, in addition, are laborious to separate.[41
These side reactions can be suppressed with low concentrations of SO, and short reaction times, but then mixtures of
products with different degrees of sulfonation are formed. Phosphanes with a low degree of sulfonation, on the other hand, lead
to an increased loss of the catalytically active (noble metal)
complexes through extraction into the organic phase because of
their poor water-solubility.['"] Both disadvantages-phosphane
formation and low, nonuniform degree of sulfonation-frequently militate against the industrial use of sulfonated phosphanes. In the following we show how these problems can be
avoided.
Treating the standard ligand triphenylphosphane (TPP) according to the previous standard procedure at 20 "C with 30 YO
oleum (30 wt% SO,) under laboratory conditions yields, after
24 hours, a mixture of sulfonated products containing 12.4 mol%
of phosphane oxides (Fig. 1 a ; 31PNMR: 6 = 36.45), which must
be separated from the sulfonated derivatives by a multistage
e~traction.1~1
We have now discovered that the addition of orthoboric acid
to the sulfonation charges lessens the phosphane oxidation or
suppresses it completely. The boric acid is initially dissolved in
2
'
\#
II
it
I
I
"
New Process for the Sulfonation of Phosphane
Ligands for Catalysts**
Wolfgang A. Herrmann,* Guido P. Albanese,
Rainer B. Manetsberger, Peter Lappe,
and Helmut Bahrmann
1
Two-phase procedures have opened a new perspective for
organometallic homogeneous catalysis as exemplified in hydroformylation.['' Sulfonated phosphane ligands have proved
themselves in the Ruhrchemie/Rhbne-Poulenc process''. 2] and
suggest that a large potential may be anticipated for other C-C
coupling reactions, t 0 0 . I ~Fuming
~
sulfuric acid (oleum), often
the only effective sulfonating agent for arylphosphanes is not
always satisfactory as a reagent for synthesis:[3d1parallel to the
Angrw. Chmi. Int Ed. Engl. 1995. 34, N o . 7
C]
"1
8
--
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30
20
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[*I
Prof. Dr. W. A. Herrmann. G . P. Albanese, Dr. R . B. Manetsberger
Anorganisch-chemisches Institut der Technischen Universitiit Munchen
Lichtenbergstrasse 4. D-85747 Garching (Germany)
Telefax: lnt. code + (89)3209-3473
Dr. P. Lappe. Dr. H. Bahrmann
Hoechst AG. Werk Ruhrchemie, D-46128 Oberhausen (Germany)
[**I Water-Soluble Metdl Complexes and Catalysts, Part 8. This work was supported by the Bundesministerium fur Forschung und Technologie. Part 7: W A.
Herrmann. C. W. Kohlpdintner. R. B. Manetsberger. H. Bahrmann, H.
Kottmann. J. Mol. C u d . , in press.
\
--
40
7
10
--
0
/I'
(I
wcw
-10
-6
Fig 1 d) "PNMR spectrum of triply SUlfOndted triphenylphosphane 2 (TPPTS,
6 = 2 88, 53 8 mol%), prepared according to the conventiondl procedures
of ref [4], crude hydrolysis mixture with 33 8 mol% of I b) "P NMR spectrum of
doubly sulfonated triphenylphosphane 1 (TPPDS), prepared with H,SO,/B(OH),/
oleum see text The spectrum shows a very smdll amount of phosphdne oxide
(6 = 37 68)
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96% sulfuric acid. The water that forms in the process [Eq. (a)]
is then quantitatively "titrated" by oleum to H,SO, [Eq. (b)],
NOH),
+5H,SO,e
[H,SO,]+
+ 3 SO,
3 H,SO,
3 H,O
+ [B(OSO,H),]- + 3 H Z 0
S03Na
SO,Na
S0,Na
(a)
(b)
6,03Na
which removes the sulfur trioxide and simultaneously generates
a superacidic medium [Eq. (a)],'5a1which apparently shows no
significant oxidizing power. According to Gillespie et al., the
Hammett acidity Ho of the system H,SO,/B(OH),/SO, at low
SO, concentrations increases substantially faster than that of
the H,SO,/SO, system at the same SO, concentration. In the
"B NMR spectrum apart from the signal of a three-coordinate
boron species (h1,, = 425 Hz, 6 = - 0.1 l), a signal of a highly
symmetrical four-coordinate species (h1,, = 61 Hz, 6 = - 3.21)
is observed on addition of B(OH), to 96% H,SO,. This resonance is likely to correspond to the borate [B(OSO,H),]-, an
assignment supported by the values for the comparable systems
B(OSO,CF,), and [B(OSO,CF,),]-, which have signal widths
at half height of 198 and 53 Hz, respectively (CH,CI,; "B
N M R : 6 = -1.11 and -3.53,respectively).[61Asshownby "B
NMR spectroscopy (Fig. 2), the equilibrium (a) is shifted completely to the right when the water produced by the reaction is
removed by o h m [Eq. (b)]. These reactions may be followed
easily through the electric conductivity of the solutions.[5b1
-10
-20
-30 -40
-8
-io
-50
-30
b)
1 (TPPDS)
2 (TPPTS)
3: R = CH3
4: R = OCH,
SO,Na
5 (BINAS-8)
Ar = C,H,-rn-SO,Na
6
is sulfonated with an excess of 30 wt % SO, at room temperature
for three days. TPPTS already has industrial application.[' - 3 , 'I
2) The common ligands in homogeneous catalysis can now be
exhaustively sulfonated without side products. Thus, within three
days at 95 "C, tris(2-methylphenyl)phosphaneaffords the triply
sulfonated phosphane 3, a new ligand that enables comparative
kinetic studies because of its ortho substitution. The deactivated
tris(2-methoxypheny1)phosphanecan be converted into the new
triply meta-sulfonated phosphane 4 with H,SO,/B(OH),/SO,
[Eq. (a) and (b)] at room temperature within four days.
3) Highly sulfonated and therefore sufficiently water-soluble
phosphanes can often be prepared only by this procedure. Thus
with 1,l'- binaphthalene - 2,2'- diylbis(methylene)bis(diphenylphosphane) (NAPHOS) only a mixture of four- to eightfold
sulfonated species is achieved by conventional sulfonation with
oleum (65% SO,) (Fig. 3a), whereas now the product BINAS-8 (5, n = 8) can be prepared selectively without phosphane
oxidation for the first time (Fig. 3b; 31PNMR: 6 = -10.44).[81
However, an excess of SO, is required in this case. The
a)
40
30
20
io
-8
o
40
Fig. 2. a) "BNMR spectrum of boric acid in concentrated sulfuric acid. b) I i B
NMR spectrum of a) after addition of oleum; see text.
The boric acid effect stems from cooperation of two favorable
circumstances: 1) The phosphanes to be sulfonated are quantitatively quaternized [Eq. (c)], which provides stability against
oxidation. 2) Sulfonating species that are far weaker in oxidizing
power than SO, are formed, for example [H3S04]+.
PR,
+ [H3S04]+
-
[HPR,]'
+ H,SO,
(4
The new process is advantageous for the following reasons:
1) For the first time a controlled sulfonation is possible: For
example, we obtain selectively the disulfonated derivative TPPDS
(1, Fig. l b ; "P NMR: 6 = -3.38) from TPP if the temperature
of the sulfonation is 58 "C, whereas it is otherwise only accessible in a mixture. This conversion is virtually quantitative after
three days. Interestingly even at 120 "C no further sulfonation to
the triply sulfonated TPPTS (2) takes place, although noticeable
phosphane oxidation occurs. TPPTS forms readily, however, if I
812
0 VCH
Verlugsgesellsrhaft mbH, 0-69451 Weinheim, 199s
-
40
-30
20
-
10
-0 -1 0
-8
Fig 3 a) Sulfonation ofNAPHOS with oleum (65 % SO,) The actual SO, concentration IS only 40% as a result of dilution with 96% H,SO, (used to predissolve
NAPHOS) The "P NMR spectrum shows the formation of phosphane oxides
(6 = 35-37) and a mixture ofmany different sulfonated derivatives (6 = - 6 to 11)
b) Sulfonation of NAPHOS with H,SO,/B(OH),/oleum (with the same SO, concentration as in a)), see text The "P NMR spectrum confirms the uniformity of the
product BINAS-8 (5) The amount of phosphdne oxides (6 = 36-37) is about
3 mol %
0570-OX33/9S~0?0?-0X12$ 10.00+ .2S/O
Angew. Chem. l n t . Ed. Engi. 1995, 34, N o . 7
catalyst formed by this ligand with rhodium(1) is the most
efficient to date for propene hydroformylation with respect to
activity, productivity, and n/iso s e l e ~ t i v i t y . ~ ~ ]
4) A sulfonation of the phospholes, in particular, failed previously because of the pronounced sensitivity to oxidation of this
class of compounds. Now from 5-phenyl-5H-dibenzophosphole
at 145' the selectively sulfonated product 6 can be obtained after
15 h in almost 90% yield as the first known water-soluble phosphole.[*I Phospholes are very promising ligands, inter alia for the
hydroformylation of higher (and also functionalized) olefins.['"]
5 ) The excess boric acid is virtually completely removed in the
hydrolytic product workup.
Studies into the kinetics of the sulfonation of triphenylphosphane point to different sulfonation species in the H,SO,/
B(OH),/SO, system: Under identical conditions, in particular the
same SO, concentration, highly sulfonated derivatives are formed
more quickly than with the conventional H,SO,/SO, system.
Probably the active electrophilic species in addition to SO, is
essentially [H,SO,]+,[' which according to Equation (a) is
present in higher concentrations.
In the light of the rapid development of two-phase catalysis,
in particular with water as catalyst medium, the process described here for the direct sulfonation should represent an important breakthrough in catalyst development mainly as a consequence of its efficiency.
Experimental Procedure
Disodium P-phcnyl-3,3'-phosphanediylbis(benLcnesulfonate)
I . Orthoboric acid
(4.80g. 77.8 mmol) was dissolved in concentrated sulfuric acid (96%, 20 mL).
Oleum (20 mL. 65 w t % SO,) w a r added dropwise ro that in the sulfonation mixture
a SO, concentration ofabout 0.9 w t % resulted. This excess SO, was removed undcr
high vacuum at 60' C within 45 min. Then triphenylphosphane (3.00 g. 11.4 mmol)
was added (boric acid'phosphane = 6.8'1). The mixture was stirred until all solids
were completely dissolved. heated to 58 -C for 4 days, and after cooling hydrolyzed
with 50 mL degassed water. The extraction was performed with triisooctylamine
(16 mL) in toluene (49 mLj. The organic phase was wished with H,O (3 x 20 mL)
)
to remove thc boric acid completely. Afier reextraction with NaOH ( 7 . 5 ~ to
p H = 11.8, the aqueous phase was neutralized with 3 M H,SO,. evaporated to dryness under vacuum. and the solid residue extracted with CH,OH (40 mL). After
reinoval of the sohent fi-om the extract. 1 was recovered a s a white glassy solid.
Yield 4.69 g (94%). cori-ect elemental analysis for C. H, Na. P, S, 0
Trisodium 3.3'.3"-phosphanetriyltris(4-methylben~enesulfoiiate)
3: Orthoboric acid
(0.40 g, 6.6 mmol) was dissolved in concentrated sulfuric acid (96 %, 3 75 mL). after
which tris(2-methylphenyljphosphane(0.50 g, 1.4 mmol) was dissolved in the mixture. Oleum (6.75 mL, 65 w t % SO,) was added dropwise LO the NI-saturated solution, which had been cooled to 0 ' C . After stirring for 3 days at 25 C. the mixture
was liydroly7ed on ice and extracted with triisooctylaniine (2 mL) in toluene
(20 mL) and worked up further a s for I [I?]. Yield 95%, correct elemental analysis
for C, H, N a . P, S. 0.
Trisodium 3,3',3"-phosphanetriylti-is(4-melhoxybenzenesulfon~ite)
4 was prepared
analogously to 3.
Disodiuin 5-(3-sulfonntophenyI)-5~-dibenzophosphole-3.sulfoiiate 6: Orthoboric
acid (2.40 g. 38.4 mmolj was dissolved in concentrated sulfuric acid (96%, 8 mL).
Oleum (1 0 mL. 6 5 wt YOSO,) was added dropwise so that i n the wlfonation mixture
a SO, concentration ofabout 5.6 wt "h resulted. This excess SO, was removed under
high vacuuin at 60 'C within 45 min. 1:inally 5-plienyl-511-diben/ophosphole
(500 mg, 1.9 minol) u a s addcd (boric acid!phosphane = 20, I ) , and the mixture was
stirred until all solids had dissolved. The charge was heated for 15 h at 145
after cooling hydrolyTed with degassed water (20 m L ) . The extraction was achieved
with triisooctylamine (4 inL) in toluene (30 mL). The further workup of the product
was as for I 1121. Yield: X52 mg (89 "h).
[2] a ) B. Cornils, E. Wiebus. Cheni. /rig. Techn 1994, 66. 916--923;
h) B. Cornils. J. Hibbel. W. Konkol. B. Lieder, J. Much, V. Schmid,
E. Wiebus (Riihrcheniie AG). DE-B 3234701, 1982 [ C h m . A h t r . 1984, 100,
194022kl.
[3] a ) Y. Tokltoh, N . Yoshimura (Kuraray Co.) EP-A 2x7066, I988 [Chrni. Ahsrr.
1989. 110. 78070g1; b) N. Yoshimura. M . Tamura, T. Higashi, K . Hino. M.
Murasawa (Kuraray Co ), EP-B 04362226, 1991 [ C h m . Ahstr. 1991, 115,
158508z]: c) C. Mercier. P. Chabardes. Pure AppL Chan. 1994, 66, 1509
1515: d) Alternative methods (indirect sulfonation): 0. Herd, K . Langhans, 0 .
Stelzer. N. Weferling. W. Sheldrick. A n g ~ w .Clzrrn. 1993, 105, 1097-1099;
Angrw. Chem. f n t . Ed EngI. 1993. 32, 1058-1059; H . Herd, A. Kessler, K . P.
Langhaus, 0. Stelrei-. W. Sheldrick. N. Weferling. .L Orgunornet. Chern. 1994,
47.5, 99-111.
[4] B. Cornils. P. Lappe. R. Gdrtner, H. Springer (Ruhrchemie AG), EP-A
0107006, 1983 [Chrni. Ab.vtr. 1984, i0f. 55331tl.
[5] a) R . J. Gillespie. T. E. Pcel, E. A . Robinson, J. An?. Chenz. Soc. 1971, 93,
5083 - 5087; b) S.1. Bass, R. H . Flowers. R. J. Gillespie, E. A. Robinson. C.
Solomons, J. C h m . Soc. 1960, 4315-4339.
[6] G. A. Olah, K . Laali. 0 . Farooq, J. OrK. CIirrn. 1984. 49, 4591
4494.
[7] a) E. G. Kuntz (Rhbne-Poulenc S. A,), F R - B 2366237, 1976 [Chem. Ahstr.
1977, 87. 101944111; b) E. G. Kuntz (Rhbne-Poulenc S. A . ) , FR-B 2733516,
1978 [Chrrn. A h r r . 1978, 88. 152026tl.
181 Assignment ofconstitution by 2D N M R spectroscopy; W A . Herrmann, G. P.
Albanese. R. B. Manetsberger. R. Schmid, W. R. Thiel, unpublished results.
Characterization of 5: ' H - ' H - C O S Y N M R (D,O): 6 = 3.62 (d, 'JHH=
13.8 Hz. 2H. HH'). 3.66 (d, 'JHH
= 13.8 Hz. 2H. HH'). 7.20 (d, 'Jl,,, = 6.9 Hz,
' J p r , = 6 . 8 H r . 1 H . H l 6 ) . 7 2 1 (d, ' < , , , = 6 , 9 H 7 . 3 J , , , = 6 . 8 H ~ ,I H . H t 6 ) ,
7.52 (tr, 'JHH
=7.7 Hz, 2 H , HIS'). 7.66 (tr. 'JHH
=7.6 HL, 2 H , HIS). 7.71 (d,
'JHH
=7.5 Hz, 3Jp,,
=7.2 HZ. 1 H, H16). 7.73 (d. 'J ,,,, =7.5 Hz, 3Jp,,=7.2 Hz,
1H.Hl6),777(d,3J,,=9.0H~.2H,H5),7.90(d,3J,,,=5,4Ha,2H,H12'),
7.97(s, 2H, H3). 7.98 (d. '&=7.53 Hz, 2 H . H 1 4 j , 8.05 (d, 'JP,,= 5.8 Hz,
2H. H12), 8.10 (d, 'JlgH - = 7 71 HL, 2 H . H14), 8.70 (s, 2 H . H8), 8.98 (d,
'J,., = 9.0 Hz, 2 H , H6).
[9] W. A. Herrmann. C. W. Kohlpaintner, R. B. Manetsberger, H. Bahrmann, H.
Kottmann, J. Mol. Catnl., in press.
[lo] D. Neibecker. R. Reau, J Mol. Cutul. 1989, 57, 153-163.
[I 11 a) H. Cerfontain, Mrchani\lic Aspcct~In .4romutii Sulfonutiori and Dr.sirl/onut i o n . Interscience. New York. 1968; b) H . Cerfontein, C. W F. Kort. / n r . .I.
Sulfur Cliem. Part C 1971, 6. 123-136.
[I21 Characterization o f 3 . "P{'H/ N M R (D,O): 6 = - 22.8; ' H N M R (D,O):
6 = 2.27 (s, 9 H ; CH,), 7.17 (dd, 3J,,p
= 4.0 Hz, 'JHH
=1.8 Hz. 3 H ; Hh), 7.35
(dd. 'JHH
= 8.1 Hz, 'Aip = 4.7 H z ~ 3 H ; H3). 7.79 (dd, 44,11
= l . 5 H7,
'.J,rp=7.9 Hz, 3 H . H4); ' C - i ' H ) N M R (D,O): 6 =146.5 (d. 'JCp= 25.8 HL,
C S ) , 141.41 (s. C l ) . 133.57 (d, 2 J , , , = 1 1 . 0 H ~ ,C 2 ) . 131.3 (d. 'JC,=4.8Hz,
C 3 ) , 129.78 (s, Cb), 126.88 (s, C4), 20.65 (d, 3Jcp
= 20 5 HI, CH,). - Characterization of 4 : "P{'H) NMR (D,O): 6 = 31.99 (s); ' H N M R (D,O):
6=3.78(~,9H;OCH,),7.20(dd,'J,,,= 8.9Hr,'J,,,, = 4 . 6 H z . 3 H ; H 3 ) . 7 . 2 4
(dd, 4JHH
= 2.3 H L 'JlI,, = 4.6 H7, 3 H ; H4), 7.93 (dd, 'JMH
= 2.1 HL,
'JI.H
= 9.6 Ha, 3 H ; H6); "Ci'HI N M R (D'O): d = 56.24 (s. OCH,). 111.41
(s,C4),122.17(d,'Jr,=11 5H~,C5),129.31(s,C6),131.05(d.~J,,=2.9H~.
C 3 ) , 136.78(d. 'Jcp =1.0 112, C l ) , 163.12(d, 'JCp=14.8 Hz, C?).-Characterization of 6 : " P ( ' H ) N M R (D,O): b =17.42; 'H-'H-COSYNMR (D,O):
h =6.90 (dt. 3J,111
=7.3Hz. '5 ,,,,=1.9Hz. 2 H ; H8, H Y ) , 7.01 (tt, 3J,,,,=
7.7H2, 4 J H p = 1 2 . 0 H ~'J. ,,,, = l . Z H 7 , 1 H : H16). 7.06 (td. ' J J , , = 7 . 7 H ~ ,
"JHp
= 3.2 Hz, 1 H: H15), 7.20 (dd, 'JIH = 8.0 Hz, 'JHP= 4.4 Ha, 1 H ; H l ) ,
=14.0 Hz,
7.32 (dt, 3Jl,ll =7.3 Hz, 'J,<,, =1.9 Hz, 2 H ; H6, H7), 7.43 (dt. 3J,,p
4.44br~ 1 . Hz,
2
1 H ; H12), 7.55 (ddd. '.A,,, = 7.7 Hz. 'J,,,,14= 1.8 Hr.
'JHHli
= 1.3 HL, 1 H; H14), 7 81 (dd. 'JHH= 8.0 H7, 4JHH = 2.0 HL, 1 H, H2),
= 2.0 HL, 1 H : H4). The numbering of the atoms
8.41 (dd. ,JHI> = 14.0 Hz, 'JHH
in 3, 4, and 6 is arbitrary.
~
Received: August 9, 1994 [Z7220IE1
Publication delayed at the authors' request
German version: Angeii Chcni. 1995. 107. 893
Keywords: catalysis . phosphane ligands . sulfonation
[ l ] a) W. A. Herrmann. C. W. Kohlpaintner, Angcu.. Clieni. 1993, 105, 1588-1609;
Angcw. Chen7. Int. Ed. Et7gl 1993. 32, 1524-1544, b) P. Kalck. F. Monteil,
A h . Orgmornct. Chain. 1992, 34. 219 - 284: c) E. Cj. K u n t r , CHEMTECII
1987. 17, 570 575.
Angrit,. Chcm. h i . Ed. Engl. 1995, 34. No. 7
:(>
VCH Ct.rlug.\g~~ell.schuJtm b H , 0-69451 Weinlieim, 1995
0570-#833/95:0707-0813 S 10.00+ 2.510
813
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