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New AuPt2 A-Frame Cluster Complexes.

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the region of olefinic carbon atoms and the phosphorus
resonance exhibits the expected diamagnetic shift
(6= - 130.2) relative to 7 (6=314.8).
The mixture of products formed under the same conditions upon "prolonged" photolysis (13 h)I4] of 7 demonstrates that the two isomers 8 and 14 are the photochemical secondary products of the phosphaprismane 10, which
is the primary product formed upon irradiation of 7.Chromatographic separation of the products affords only 8
(m.p.=71 "C; yellow crystals) and 14 (m.p.=76"C; colorless crystals; ratio = 1 : 1). Observation of this reaction by
"P-NMR spectroscopy reveals that, in the photolysis solution maintained at -4O"C, only 14 (6= -83.3) and apparently another phosphabenzvalene 13 (6= - 89.8) are present, but no 8. Upon workup (20"C), the isomer 13 is transformed thermally into the phosphinine 8. A clear picture
of the reaction is afforded by irradiation of 8 at -40°C,[4'
which gives oniy 13 (3'P-NMR); upon thawing of the solution, the heteroaromatic compound 8 is formed once
again.
The formation of the phosphabenzvalenes 13 and 14
from 10 can be explained as follows: either the C-2/C-3
and the C-4/C-5 bonds (-11) or the C-5/C-6 and C-4/
C-3 bonds (-12) are broken and the diradicals thus
formed lead to product formation (11-13 (-8) and
12 -+ 141.
The constitution of the phosphabenzvalenes is in accord
with their N M R spectra (Table 1). An X-ray crystal structure analysis was carried out for the phosphinine 8 ; it reveals a twisted boat form, which is due to steric factors;
the atoms C-2 and C-5 correspond to the "stern" and the
"bow," respectively. The angles formed with the idealized
plane of the base are 17.9" (twisting around the P1/C3
axis) and 33.7" (twisting around the C4/C6 axis). To the
best of our knowledge, this is the largest deviation of an
aromatic o r heteroaromatic ring from planarity observed
so far.'']
[4] Philips HPK 125-W high-pressure mercury lamp, Pyrex filter, CDClr.
151 The sterically bulky substituents of 8 result in C-C-C and P-C-C interior angles ( I 16.8-124" and 118.4-1 19.8", respectively) that deviate from
the normal values, as well as a small increase in the bond lengths of the
six-membered ring (P-C distances: 1.730 and 1.758 A ; C-C distances:
1.402-1.437
For further details, see G. Maas, J. Fink, H. Wingert, K.
Blatter, M. Regitz, Chem. Ber. 120 (1987), in press.
[6] L. D. Quinn: The Heterocyclic Chemistry of Phosphorus. Wiley, New York
1981, p. 204.
[7] The bond lengths and angles of 5 are in the usual range and exhibit n o
unusual features. The two phosphacyclobutene structural units
PI,C2,C3,C4 and PI,C4,CS,C6 are planar within five and three standard
deviations, respectively; the puckering angle is 117.1". J. Fink, M. Regitz,
unpublished results, Universitat Kaiserslautern 1986.
A).
New AuPtz A-Frame Cluster Complexes**
By Gilles J. Arsenault, Ljubica ManojloviC-Muir,*
Kenneth W . Muir, Richard J. Puddephatt,* and
Ilse Treurnicht
The chemistry of the metal-metal bond in diplatinurn( I )
complexes such as 1 and in analogous gold(1i) complexes
has been developed rapidly, and many fundamental reaction pathways of binuclear complexes have been
Although many unsaturated and electrophilic reagents add
to the metal-metal bond of 1 , no direct additions of electrophilic metal fragments to form cluster complexes have
been found.[31For example, whereas "CH2," from CH2N2,
adds to the metal-metal bond of 1 , the isolobal SnCI, inserts into a R-C1 bond i n ~ t e a d . [ ~We
. ~ ] report here that
electrophilic gold fragments, AuX or AuPPh:, add to the
R-Pt bond of 1 whereas similar copper or silver fragments
d o not.
+
' z r v rrr'
.s,
2a, L = PPh,
2b. L = Ph,PCH,PPh,AuCL
1
110-120~C
>
2 c . L = Ph,P(CH,),PPh,AuCL
14
Y
Finally, heating of the phosphabenzvalene 14 with sulfur in the absence of solvent (12 h, 110-120°C) results in
formation of the 1-Dewar-phosphinine sulfide 15
(m.p.= 107"C, colorless crystals, yield 65%). The 'H- and
I3C-NMR spectra reveal the consequences of the resulting
C, symmetry (Table I). The chemical shift of the phosphorus (6=39.3) corresponds to that found for 1-methyl-1phosphacyclohexane 1-sulfide (6= 33.9).@]Furthermore, a
crystal structure analysis of 15 is available.[71
Received: September 15, 1986 [Z 1930 IE]
German version: Angew. Chem. 99 (1987) 67
[ I ] J. Fink, W. Rosch, U.-J. Vogelbacher, M. Regitz, Angew. Chem. 98 (1986)
265; Angew. Chem. Inr. Ed. Engl. 25 (1986) 280.
[2] Biichi MPLC system 681, column: 46x2.6 cm, Merck silica gel (1525 pm), petroleum ether/ether 30: 1.
[ 3 ] Dewar benzene/Dewar-benzene isomerization: G. Maier, K. A. Schneider, Angew. Chem. 92 (1980) 1056; Angew. Chem Inr. Ed. Engl. 19 (1980)
1022: H. Wingert, M. Regitz, Chem. Ber. 110 (1986) 244; Dewar-pyridBull. Sac. Chim.
ine/Dewar-ovridine
isomerization: J. Fink, M. Re.&,
.Fr. 1986. 239.
86
0 VCH Verlagsgerellrchafl mbH. 0-6940 Wemheim. 1987
Ph,P-PPh,
Y"
30, X
3b, X
3c. X
3d, X
= Y = CL
= Y = C-CtBu
= C-CtBu, Y = CL
= CECtBu, Y = I
Reaction of 1 with [Au(N03)(PPh3)] or [AuCI(SMe,)]
gave the cationic 2a or neutral 3a, respectively, in nearly
quantitative yields. They have NMR spectra typical of Aframe c ~ m p l e x e s . [ The
~ . ~ ~complex 3b,I6' prepared by reaction of [Pt2(p-dppm)3][71(dppm = Ph2PCH2PPh2) with
[*] Dr. Lj. Manojlovic-Muir, Dr. K. W. Muir
Department of Chemistry, University of Glasgow
Glasgow GI2 SQQ, Scotland (U. K.)
[**I
Dr. R. J. Puddephatt, Dr. G. J. Arsenault, Dr. I . Treurnicht
Department of Chemistry, University of Western Ontario
London N6A 587 (Canada)
This work was supported by N.S.E.R.C. (Canada) and S.E.R.C. (U.K.).
0570-0833/87/0101-0~86$ 02.50/0
Angew. Cheni. I n r . Ed. Engl. 26 (1987) No. I
AuC=CtBu,[81reacted with CH,CI, to give 3c. Complex 3c
reacted with Nal to give 3d,I6] whose structure was determined crystallographically (Fig.
Pt2Au cluster. The PtAu [2.656(2) and 2.661(2) A] and RPt
[2.837(1) A] separations are all indicative of bonding interactions. The clusters 2 and 3 are therefore considered to
contain a 3-center-2-electron Pt2Au group, in which the
platinum and gold atoms have 16e and 14e configurations,
respectively. These complexes are the first examples of 42e
Pt2Au clusters. The only other known trinuclear R-Au
cluster is the 40e cluster complex 8.1''1
[PtCt(PEt3)z(A~PPh3)z]@8
Within the coinage metals, it is clear that gold has by far
the greatest ability to form heteronuclear RM (M =Cu,
Ag, Au) bonds.
Received: September I, 1986;
revised: October 13, 1986 [ Z 1913 IE]
German version: Angew. Chem. 99 (1987) 79
Fig. I . The molecular structure of 3d, with carbon atoms not labeled and the
atomic thermal ellipsoids displaying 20% probability. Selected bond lengths
[A] and angles ["I are: Au-I 2.580(2), Pt-P 2.274(5)-2.289(6), R - C 2.01(3),
2.02(3); Pt-Au-Pt 64.5(1), A u - P - C 151.0(7), 151.7(6), Pt-C-C 172(2), 177(2).
Further details of the crystal structure investigation are available on request
from the Director of the Cambridge Crystallographic Data Centre, University Chemical Laboratory, Lensfield Road, Cambridge CB2 1 EW (U.K.),
upon quoting the names of the authors and the journal citation.
In contrast to the ease of formation of Pt2Au clusters as
described above, it has not yet been possible to prepare
derivatives of silver o r copper. Thus, reaction of 1 with
[M(N03)(PPh,)], M = C u o r Ag, gave 4 and MCI (replacement of CI' by PPh3). Similarly, reaction of 1 with one or
two equivalents of [Cu(MeCN),]@ gave 5a or 5b, respectively, and CuCI. Reaction of 1 with excess CuCl gave a
1 : 1 adduct; however, it was not an A-frame complex but
was tentatively assigned the unusual structure 6, involving
the addition of CuCl to a chloride ligand of 1 . Complex 6
was fluxional in solution, and solutions slowly deposited
CuCI. A useful citerion of structure of 6 was the low-tem-
6
perature '"Pt-NMR spectrum,[61which gave two signals
due to nonequivalent Pt atoms, and the coupling constant
'J(PtPt)(10334 Hz), which was greater than in the parent
1 (8145 Hz"O1); the A-frame clusters have lower 'J(PtPt)
values: 6 9 8 0 f 5 0 Hz and 6200k 100 Hz for complexes 2a
and 3a, respectively.
Some digold reagents gave behavior of both gold and
copper/silver reagents. Thus reaction of 7,n = 1 or 2, with
two equivalents of 1 gave 2b o r 2c respectively, and
[Pt2CI(NO,)(g-dppm),]. The first gold atom adds to the PtPt bond of 1 , while the second gold abstracts chloride
from the second molecule of 1 . We believe that steric hindrance prevents the expected formation of bridged bis(Aframe) complexes in these cases.
The structure of 3d (Fig. 1) shows that the AuI fragment
symmetrically bridges the Ptz unit to form a triangular
A n g r n Chem I n ! Ed Engl. 26 (1987) No. I
[ I ] R. J. Puddephatt, Chem. SOC.Rev. 1982. 99, and references cited therein.
121 a) H. Schmidbaur, C. Hartmann, Angew. Chem. 98 (1986) 573; Angew.
Chem. I n f . E d . Engl. 25 (1986) 575; b) H. Schmidbaur, T. Pollok, R.
Herr, F. E. Wagner, R. Bau, J. Riede, G. Miiller, Organometailics 5
(1986) 566; c) H. H. Murray, J. P. Fackler, Jr., A. M. Mazany, ibid. 3
(1984) 1310; d) S. L. Schiavo, G. Bruno, P. Piraino, F. Faraone, ihid. 5
(1986) 566: e ) W. A. Herrmann, W. Kalcher, Chem. Ber. 118 (1985)
3861; 0 R. Uson, A. Laguna, Coord. Chem. Rev. 70 (1986) I .
[3] Y. Yamamoto, K. Takahashi, H. Yamazaki, J. Am Chem. SOC. 108
(1986) 2458.
[4] K. A. Azam, A. A. Frew, B. R. Lloyd, Lj. ManojloviC-Muir, K. W. Muir,
R. J. Puddephatt, Organorneiallics 4 (1985) 1400.
151 M. C. Grossel, R. P. Moulding, K. R. Seddon, fnorg. Chim. Acta 64
(1975) L275.
[6] 2 a : yellow needles, m.p.= 182-220°C (dec.): NMR spectra in CD2C12:
' H : 6=3.56 [m, 2H, 'J(H.'H")= 14, 'J(PH)=S, 'J(PtH)=20 Hz;
2xCH"Hh], 5.02[m,2H, 'J(H"Hh)=14, 'J(PtH)=112 Hz; 2xCH,'Hh];
"P: 6 = 8 . 3 I'J(PtP)=2400, 'J(PtP)= - 100, 'J(PP)=62, 4J(PP)=26 Hz:
P of dppm], 36.5 ['J(PP)=600 Hz; PPhJ 3a: red platelets, m.p.=235245°C; NMR spectra in CD2C12: ' H : 6=4.10 [m, 2H, 'J(H,'Hh)= 14,
'J(PH)=5, 'J(PtH)=20 Hz; 2 x C H ' H h ] , 4.69 [m, 2 H , 'J(H"Hh)= 14,
'J(PH)=2, 'J(PtH)= 112 Hz; 2 x C H " H h ] ; "P: 6 = 9 . l ['J(PtP)=2410,
'J(PtP)= -78, 'J(PP)=59, 'J(PP)=25 Hz; P o f d p p m ] . 3b: NMR spect r a i n C6D,: ' H : 6 = 0 . 8 9 [ s , 18H; ZxrBuCCPt], 1 . 6 9 [ ~ , 9 H : t B u C C A u ] ,
4.93 [m. 2 H , 'J(H"Hh)=l3, 'J(PH)=S Hz: 2 x C H H h ] , 5.26 [m. 2H.
'J(H"Hh)= 13, 'J(PH)=2, 'J(PtH)=97 Hz; 2xCH"H"j: "P: 6=8.71
['J(PtP)=2556, 'J(PtP)= -45, *J(PP)=69, 'J(PP)=25 Hz; P of dppm].
3d: NMR spectra in CD2C12: ' H : 6=0.58 [s. 1 8 H ; 2xtBuCCPt1, 4.62
[m, 2 H , 'J(H"Hh)=13, 'J(PH)=6 Hz; 2 x C H " H h ] , 5.48 [m, 2 H ,
'J(H*Hh)=13, 'J(PH)=2, 'J(PtH)=90 Hz; 2 x C H " H h ] ; "P: 6=8.90
['J(PtP)=2509, 'J(PtP)= - 18, 'J(PP)=64, 4J(PP)=25 Hz: P of dppm].
6: orange prisms, m.p.= 195-240°C (dec.): NMR spectra in CDZCl2at
-70°C: "P: 6= 11.9 [m, 'J(PtP)=2860; PI, -4.3 [m, 'J(PtP)=2760;
Ph]; 'SSP(K,[PtCI,] as standard): 6=652.9 [m. 'J(PtP)=2270,
'J(PtP)= 105, 'J(PtP)= 10334 Hz: Pt"], 314.5 [m, 'J(PtP)=2860,
'J(PtP)= 153, 'J(PtPt)= 10334 Hz; a h ] . Good analytical data have been
obtained for all new complexes (2, 3, and 6).
[7] M. C. Grossel, M. P. Brown, C. D. Nelson, A. Yavari, E. Kallas, R. P.
Moulding, K. R. Seddon, J. Orgonome/. Chem. 232 (1982) C 13.
[S] G. E. Coates, C. Parkin, J. Chem. SOC.1962. 3220.
[9] Orthorhombic, space group Pn42, (No. 33), a=29.053(4), h= l6.131(3),
c=13.956(3)A,
V=6540.5AJ,
2=4,
p '.,,' d = 1.671 g c m - ' ;
F(000)= 3 128, MoKur1 =0.71069 A, p(MoK.) = 7 1.4 cm - I . Intensity data
were measured at room temperature on an Enraf-Nonius CAD4 diffractorneter. The structural model-included dppm hydrogen atoms in calculated positions (d(CH)= 1.0 A); the phenyl rings were constrained to
6/mmm symmetry with d(CC)= 1.38
Only Au, Pt, P, and I atoms
were assigned anisotropic thermal parameters. The least-squares refinement gave R =0.040 and R,= 0.050 for 4442 unique, absorption-corrected reflections with l > 3 a ( l ) .
[lo] M. C. Grossel, J. R. Batson, R. P. Moulding, K. R. Seddon, J. Organomet. Chem. 304 (1986) 391.
[ I I ] P. Braunstein, H. Lehner, D. Matt, A. Tiripicchio, M. Tiripicchio-Camellini, Angew. Chem. 96 (1984) 307; Angew. Chem. In/. Ed. Engl. 23
(1984) 304.
0 VCH Verlagsgesellschaji mhH, 0 - 6 9 4 0 Weinheim. 1987
A.
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87
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