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General Method for Preparation of Multidentate Fluorophosphane Ligands.

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This desulfurization reaction not only occurs with aromatic thiols, but with benzylic and nonaromatic thiols as well.
Yields are good and product isolation is simple.
General procedure
The thiol ( I ) (1.5 mmol) in THF (2-3 ml) is added to anhydrous metal chloride (3.0 mmol) in THF (2 ml). After addition of THF (8 ml), the reaction mixture is stirred at room
temperature for 15-25 min, cooled to - 78 "C, and then a
1 M solution of Na[(C2H5),BH]in THF (6.0-6.2 ml) is added by syringe. The solution is stirred for 15-20 min at
- 78 "C, and then allowed to warm to room temperature
with stirring. Moist sodium sulfate is added, followed by water (10 ml), and the reaction mixture is filtered. The products
are then extracted from the filtrate by methylene chloride or
chloroform; further purification, if necessary, is by column
chromatography.
Received: October 8, 1979 [Z 439 IE]
German version: Angew. Chem. 92, 321 (1980)
[I] H. Alper, H. N. Paik, J . Org. Chem. 42. 3522 (1977).
121 E. C. Ashby, J. J. Lin. J. Org. Chem. 43, 1263, 2567 (1978); F. Solo, Y. Mori,
M. Solo, Tetrahedron Lett. 1979, 1405; F. Sam in Y. Ishii, M. Tsulsui:Fundamental Research in Homogeneous Catalysis. Vol. 2. Plenum Press, New York
1978, p. 81, and references cited therein.
Similar reactions also occur with primary and secondary
amines and, more slowly, with thiols. Thus, by choosing a
suitable substrate, a product may be made with almost any
desired spatial arrangement of fluorophosphino groups. Two
typical syntheses are described, that of bis[2-(difluorophosphinoxy)ethyl]sulfide (5)and that of phosphoryltrioxytris(difluorophosphane) (6).
Experimental
Preparation of (5): Compound (I)['] (4 mmol) is condensed into a glass ampoule (at -196°C) containing
S(CH2CH20H),(1.7 mmol) and the reagents are warmed to
room temperature for 45 min. After the volatile products
have been distilled out at - 78 "C, (5) (1.4 mmol, 80% yield)
is obtained in a pure form by distillation in vacuo at room
temperature. Subsequent manipulation of (5)is by syringe in
an inert atmosphere@].
Preparation of (6): Compound ( I ) (16.5 mmol) is condensed into a glass ampoule (at - 196 "C) containing 100%
H,P04 (4.5 mmol). On warming to room temperature, effervescence occurs and the solid material disappears. After 30
min, the volatile products are removed, and (6) (4.3 mmol,
95% yield) is obtained as a clear liquid, involatile at - 45 "C,
by fractional condensation in vacuoI'1.
Received September 3, 1979 [Z 440 IE]
German version: Angew. Chem. 92, 323 (1980)
General Method for Preparation of Multidentate
Fluorophosphane Ligandd"]
J. F. Nixon, Adv. Inorg. Chem. Radiochem. 13, 363 (1970), and references
cited therein.
C. A. McAulCfe, W. Leuason: Phosphine, Arsine and Stibine Complexes of
the Transition Elements. Elsevier, Amsterdam, 1979, 9. 310, and references
cited therein.
R. B. King, J. Gimeno, J . Chem. SOC.Chem. Commun. 1977, 142.
M. G. Newton, R. 8. King, M. Chang, N . S. Pantaleo, J. Gimeno, J. Chem.
SOC.Chem. Commun. 177, 531.
Preparation, see D. E. J. Arnold, E. R. Cromre. D. W. H. Rankin, J . Chem.
SOC.Dalton Trans. 1977, 1999.
'H-NMR (CDCI,): 6=2.81 (4H, t, J = 7 Hz),4.19(4H, q, J P H = J H H = ~ Hz);
"CC-NMR:6 r 3 2 . 4 (d. J p c = 3 Hz). 62.1 ( t x d , J ~ c = 9Hz, J p c = 3 Hz); 19FNMR 6 = -48 (d, J ~ = t 2 9 4Hz); "P-NMR: 6=112 (1x1, Jpp=1294 Hz,
J P H = 7Hz); IR (film): 2970, 2910, 1465, 1425, 1405, 1295, 1200, 1050, 1005,
965. 805. 760, 560 c m - '
"P-NMR (CDCL): 6 = 108 (3P, t x d , JpF=1385 Hz, Jpy=28 Hz),-41 (1 P.
m); IYF-NMR:6 = -38 ( d x d , JPF=1384 Hz, JpF=tOHz); IR (gas): 1345,
1042,988,867,728.529,469,399 cm- '; m. p. - 19 "C, vapor pressure at 0 "C,
By Ernest R. Cromie, George Hunter, and David W: H
Rankin"'
Although fluorophosphanes are well known as monodentate ligands[", very little work has been done with multidentate fluorophosphanes[21,and few suitable ligands are readily
available. They are of interest because they can bond in a
number of different ways: for example, CH3N(PF2)2may
form two bonds to a single metal atomI3Jor a bridge between
two metal atomsL4].We report here a reaction which may be
used to prepare a wide variety of fluorophosphanes which
may prove to be useful multidentate ligands.
We have observed that bis(difluorophosphino)sulfide (I)[']
reacts with organic and inorganic mono- and polyhydroxy
compounds (2) to give difluorophosphane sulfides (3) and
the desired difluorophosphinoxy compounds (4).
S(PF2)z + ROH
(1)
(2)
+
SPFZH + ROPF2
(3)
(4)
The product (4) is normally much less volatile than (3), and
may therefore easily be obtained in a pure form. Use of an
excess of hydroxy compound (2) should be avoided, as a slow
substitution reaction of (3) occurs, yielding less volatile products (SPFHR, SPHR2).
The group R may be almost any organic group, such as
primary, secondary, or tertiary alkyl, aryl or acyl, and inorganic "hydroxides" such as phosphoric acid may also be
used. With 1,2-diols PF3 is eliminated from the initial products to give 2-fluorodioxaphospholanes,which may also be
of interest as ligands.
[*] Dr. D. W. H. Rankin, E. R. Cromie, G. Hunter
Department of Chemistry. University of Edinburgh
West Mains Road, Edinburgh EH9 3JJ (Scotland)
[*'I We thank the Science Research Council for research studentships (to E. R.
C. and G. H.).
316
1 torr.
@ Veriag Chemie, GmbH, 6940 Weinheim, 1980
I9'Pt-NMR Spectroscopy of Catalytically Active
Complexes. Extremely Large Spin-Spin Coupling
between Platinum and Tin'"'
By Karl-H. A . Ostoja Starzewski and Paul S. Pregosin[']
Platinum-phosphane complexes in combination with
tin(r1) chloride are excellent homogeneous catalysts for hydrogenation and hydroformylation reactions'']. As part of
our study''] on the NMR characteristics of the active intermediates formed in these reactions, we found IJ(i9sPtit9Sn)
in tran~-[PtCl(SnCl~)(PEt~)~]
to be 28 954 Hz, which represents the largest one-bond spin-spin coupling constant ever observed (cf. Table
['I
Dr. P. S. Pregosin, Dr. K.-H. A. Ostoja Starzewski
Laboratorium fur Anorganische Chemie, ETH-Zenlrum
Universitatstrasse 6. CH-8092 Ziinch (Switzerland)
["I
This work was supported by the Swiss National Science Foundation. We
thank Prof. L. M Venand for helpful discussions.
OS?0-0833/S0/0404-031~ $ 02S0/0
Angew. Chem. I n l . Ed. Engl. 19 (1980) No. 4
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preparation, multidentate, fluorophosphane, general, method, ligand
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