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Bismuth Alkoxide Dimer Complexes Containing Planar Bi2(-OR)2 Cores Syntheses and Structures of [{Bi[OCH(CF3)2]3(thf)}2] and [{Bi(OC6F5)3(C7H8)}2] ╖ 2C7H8.

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[3] A. Subaric-Leitis, Ch. Monte, A. Roggan, W. Rettig, P. Zimmermann, J.
Heinze. J. Chem. Phys. 1990, 93,4543-4555.
[4] K. Miillen, M. Baumgarten, N. Tyutyulkov, S. Karabunarliev, Synfh.M e f .
1991. 40, 127-136.
[S] H. Hosbino, K. Kimamura, M. Imamura, Chem. Phys. Left.1973, 20,
193- 196.
[6] M. Dietricb, J. Mortensen, J. Heinze, Angew. Chem. 1985, 97, 502-504;
Angew. Chem. l n f . Ed. Engl. 1985, 24, 508-510; J. Mortensen, J. Heinze,
J. Elerfroonal. Chem. 1985, 175, 333-342; 0. Hammerich, J. M. Saveant,
Chrm. Soc. Chem. Commun. 1979,938-940.
171 0. Bayer, Methoden Org. Chem. (Houben-Weyl) 4. Aufl. 1952-, Band
713 c, 1979, p. 46.
[XI All new compounds yielded the expected spectroscopic data and elementary analyses (Table 1).
[9] 8 b by reaction of 8 d with butyl lithium; 8 d from 6b by general methods,
see A. Roedig, Meihoden Org. Chem. (Houben-Weyl),4th ed. 1952-, Vol.
514,1960, p. 254.0. Bayer, Methoden Org. Chem. (Houben-Weyl), 4 f hed.
1952- Vol. 7/3c, 1979, p. 282.
[lo] M. Rehahn. A. D. Schliiter. G. Wegner, W. J. Feast. Polymer 1989, 30,
1060-1062; U. Fahnensticb, K.-H. Koch, K. Miillen, Makromol. Chem.
Rapid Commun. 1989, 10, 563-569.
Ill] This finding is consistent with the electronic absorption spectra of the
neutral compounds (CH,CI,, 2: I,,, = 391 nm, 3a: A,, = 401 nm, 3b:
= 404 nm, 4: 2.""" = 406 nm), which reveal only a small bathochromic
shift of the longest wavelength band with increasing chain size. This may
be caused by the different substitution patterns.
1121 In particular aprotic solvents, 2 can be reversibly charged to both a tetracation and a tetraanion [6].
[13] 0. W. Howarth, G. K. Fraenkel, J. Am. Chem. SOC.1966,88,4514-4515.
,669 nm, 3 b - : I,,, = 671 nm, 4 - : I,,, = 682 nm (all mea[14] 2 - : i.,,=
surements in THF/K+).
[15] For the triplet dianion of 2 (K'/MTHF/I 50 K) we have measured a D-value of 15.8 mT.
[16] J. Brickmann, G. Kothe,J Chem. Phys. 1973,59,2807-2814; B. Kirste, H.
Am. Chem.
van Willigen, H. Kurreck, K. Mobius, M. Plato, R. Biehl, .
Soc. 1978, 100, 7505-7513.
[17] R. D. Dowsing, J. Magn. Reson. 1970,2, 332-337; J. A. Novak, R. Jain,
D. A. Dougherty, J. Am. Chem. Sue. 1989, 111, 7618-7619; E. Wasserman, R. W. Murray, W. A. Yager, A.M. Trouolo, G. Smolinsky, ibid.
1967, 89. 5076-5078; p. I. Weissmann, T. Kothe, ibid. 1975, 97, 25372538.
[18] A. Carrington, A.-D. McLachlan, lntroducfion f o Mognefic Resonance,
Harper&Row, New York, 1967, p. 130.
Bismuth Alkoxide Dimer Complexes Containing
Planar Bi2(p-OR), Cores: Syntheses
and Structures of [{Bi[OCH(CF,),],(thf)}
and [{Bi(0c,F,),(c7H8)}21
C7H8 **
By Carolyn M . Jones, Michael D . Burkart,
and Kenton H . Whitmire*
Recently, metal alkoxide compounds have been receiving
attention as precursors to high-temperature superconductors via sol-gel or vapor deposition processes. Current precursors incorporate bulky ligands in order to achieve desirable volatility or solubility. However, more controlled
syntheses might be achieved by the use of smaller ligands in
order to form complex alkoxide oligomers and clusters with
more than one metal constituent. To this end we explored the
synthesis of soluble bismuth alkoxides containing nonsterically demanding ligands. Bismuth is an important component in many superconductors with a high transition temperature such as [Bi,Sr,CaCu,O,] [Ia1 and [Sr2Bi2Cu,0,+J.11b1
Unfortunately, relatively few bismuth alkoxides have been
Dr. K. H. Whitmire, Dr. C. M. Jones, M. D. Burkart
Rice University, Department of Chemistry
P.O. Box 1892, Houston, TX 77251 (U.S.A.)
We thank the Donors of Petroleum Research Fund (administered by the
American Chemical Society) and the Robert A. Welch Foundation for
support of this work. Funds for the Rigaku AFC5S diffractometer were
provided in part by the National Science Foundation.
Angeu. Chem. l n f . Ed. Engl. 31 (1992) No. 4
structurally characterized.['] We report here the syntheses
and structures of two bismuth alkoxide dimer complexes
which act as Lewis acceptors.
The reaction of bismuth trichloride with three equivalents
of Na[OCH(CF,),] in THF results in the formation of the
tris(a1koxide) complex 1 as a T H F solvate [Eq. (a)]. The
analogous reaction with NaOC,F, does not yield a
tris(a1koxide) compound; 13] however, refluxing triphenylbismuth with HOC,F, in toluene resulted in the desired product
as a toluene solvate [Eq. (b)]. It was previously reported in
the literature that trialkylbismuth compounds do not react
with alcohols.[4]However, we have found this reaction to be
facile for phenols; the reaction of triethylbismuth with
HOC,F, or HOC,H, produces a monosubstituted phenoxybridged chain polymer.[51
+ 3 Na[OCH(CF,),]
+ 3 HOC,F,
- 3NaCI
C6H5CH3 , [(Bi(OC,F,),(C,H,CH,)),1
- 3 C,H,
Compounds 1 and 2 are structurally similar in the solid
state; each forms a loose dimer with a planar [Biz@-OR),]
ring structure (Figs. 1 and 2). The bismuth centers show a
Fig. 1. ORTEP diagram of [{Bi[OCH(CF,),],(thf)},] (1) with thermal ellipsoids drawn at 40% probability level. Fluorine and hydrogen atoms were omitted for clarity. Selected bond distances [A] and angles ["] not mentioned in text:
Bi(1)-0(2), 2.064(8); Bi(1)-0(3), 2.1 16(7); B i ( l N ( 4 ) , 2.575(7); Bi(1)-O(1)Bi(lA) 109.1(3); O(l)-Bi(l)*(lA)
70.9(3); O(l)-Bi(lW(2), 90.6(3); O(1)Bi(1)-0(3), 81.8(3); O(ltBi(l)-O(4), 165.8(3); 0(2)-Bi(lF0( 1A) 84.1(3):
0(2bBi(lE0(3), 90.6(3); 0(2FBi(lt0(4), 81.6(3);0(3)-Bi(l)-O(lA) 152.1(2);
0(3)-Bi(lt0(4), 86.4(3); 0 ( 4 t B i ( l t O ( l A ) 119.7(2).
distorted octahedral coordination geometry in which two of
the sites are occupied by asymmetric bridging alkoxide ligands (for 1: Bi(lFO(l), 2.188(7); Bi(1)-O(lA), 2.688(7) A;
for 2 : Bi(2)-0(2), 2.210(8); Bi(2EO(2A), 2.571(7) A). A
THF molecule (in 1) or toluene (in 2) is coordinated in
the site trans to the shorter bismuth-oxygen bond of the
[Bi,(p-OR)J unit. A stereoactive lone pair of electrons occupies one of the octahedral sites cis to the bridging alkoxide
ligands. Two additional alkoxide ligands complete the octahedron. Compound 2 contains additional lattice toluene.
The NMR spectra of compounds 1 and 2 in C,D, or
[D,]toluene suggest that these are not rigid structures in solution as only a single signal is observed for the alkoxy (in 1)
or phenoxy (in 2) ligands at room temperature. A second
signal appears in the "F NMR spectrum of 1 in [DJtoluene
as the temperature is lowered and is the predominant signal
at -65 "C. The temperature-dependent NMR spectra may
reflect monomer-dimer interconversion; the dimer is the
predominant species at low temperature.
Verlagsgeselischaft mbH, W-6940 Weinheim. 1992
0570-0833/92j0404-04Sl $3.50+.2S/0
Fig. 2. ORTEP diagram of [{Bi(OC,F,),(C,H,)},] . 2C,H, (2) with thermal
ellipsoids drawn at 40% probability level. Fluorine atoms on pentafluorophenoxide ligands, hydrogen atoms, and lattice toluene have been omitted for
clarity. The carbons of the pentafluorophenoxide rings are numbered sequentially from the ips0 carbon. Selected bond distances [A] and angles ["I not
mentioned in text: Bi(ltO(l), 2.147(8); Bi(lW(3), 2.088(9); Bi(lkO(2)Bi(1A) 112.3(3); O(l)-Bi(1)-0(2), 86.5(3); O(ltBi(l)-O(2A), 145.4(3); O(1)Bi(1)-0(3), 82.7(3); 0(2)-Bi(l)-0(2A), 67.7(3); 0(2tBi(lt0(3), 92.6(3);
0(2AtBi(l tO(3). 76.1(3).
Compound 2 is particularly interesting in that it is a rare
example of a bismuth-arene
complex and the first such
bismuth alkoxide. The first examples of structurally characterized bismuth-arene complexes were the bismuth trichloride adducts, [{ 1,3,5-(CH3),C6H,}(BiC13)]
and [((CH,),C,}(BiCl,)], described by Schmidbaur.t6a1Two aluminum trichloride adducts of bismuth chloride arene complexes have
also been structurally characterized.[6b1.In 2 the distance
between the bismuth atom and the toluene ring centroid is
slightly shorter than in the bismuth trichloride mesitylene
complex (2.96(4) vs. 3.07(2)
and is close enough to be
considered a real (albeit weak) interaction. The angle between the ring normal and the metal to ring center vector in 2
is 5.7" (vs. 2.1-7.3" for the bismuth trichloride adducts)
indicating an $-bound toluene molecule.
The bismuth center appears to prefer a "hypervalent" electron configuration in tris(a1koxide) compounds and readily
functions as a Lewis acid to alkoxide ligands on other bismuth atoms and to solvent molecules. Steric bulk on the
alkoxide ligands can prevent further coordination as in the
case of [Bi{2,5-Me,C,H,0},].[2"1 The bismuth centers in the
phenoxy-bridged chain polymers [BiEt,(p-OR)], mentioned
[Bi(OC,H,OMe),] oligomerizes to make each bismuth(n1)
center five coordinate with a stereoactive lone pair of electrons.IZblCompound 1 can be thought of as having four
electrons in excess of the filled octet while 2 has eight more
than needed. A similar situation exists for the bismuth atoms
in the bismuth trichloride adducts of Schmidbaur et al.
where the lone pairs are not stereoactive.[6a1The use of nonsterically demanding alkoxide ligands in 1 and 2 readily allows oligomerization which, together with the Lewis-acceptor
properties of the bismuth center, raises the possibility of
incorporation of other metal centers to form mixed-metal
alkoxide oligomers.
Experimental Procedure
Compound 1: Bismuth trichloride dissolved in THF was added to a T HF solution containing three equivalents of Na[OCH(CH,),] formed in situ by the
reaction of the alcohol with excess sodium hydride. A white precipitate resulted
Verlagsgesellsrhaft mbH, W-6940 Weinheim. 1992
immediately Removal of the THF in vacuo was followed by extraction with hot
toluene and filtration through Celite. Cooling to room temperature and reduction of volume afforded large colorless crystals of 1. Compound 1 has been
characterized spectroscopically and by single-crystal X-ray diffraction: 'H
NMR (C,D,): 6 = 5.58 (s), 3.39 (m), 1.26 (m); I9F NMR (C,D,, 297 K,
CFJOOH): d = 0.34 (d, J = 4 Hz); ([D,]toluene, 242 K) 0.172 (d, J = 4 Hz);
IR (nujol) C[cm-l] =1294 (s), 1284 (s), 1258 (s), 1188 (s), 1165 (m), 1138 (s),
1095 (s), 1022 (m), 926 (w), 889 (m), 859 (s), 850 (m). 831 (w). 744 (s), 690 (s),
684(s).Crystaldatafor 1: monoclinicspacegroup P2,/n(no. 14), T = - SOT,
(1 =13.738(7),
b =10.936(7), c =14.389(8) A, 8 = 94.53(4)", R = 0.0427,
R, = 0.0471, S = 1.766. For 326 parameters, 2786 observed reflections with
I > 341). Repeated attempts to obtain analytical data were unsuccessful because of fractional loss of THF from analytical samples.
Compound 2: Triphenylbismuth was refluxed with three equivalents of
HOC,F, in toluene for 12 h followed by filtration. A clear yellow solution
resulted from which yellow crystals of 2 grew at -20°C. Compound 2 was
characterized spectroscopically and by single-crystal X-ray diffraction : ' 9F
NMR (C,D,, CF,COOH): 6 = - 87.74 (d), -89.10 (t, J = 19 Hz), -94.44
(m); IR (nujol) C [cm-'1 = 1307 (m), 1162 (m), 1021 (s), 795 (s), 751 (m). Crystal
data for 2: triclinic space group Pi (no. 2), T = - SOT, a =11.086(6), b =
13.378(8), c =10.771(9) A, a = 98.58(7), = 95.58(5), 7 = 95.22(5)", R =
0.0591, R, = 0.0581, S =1.691 for 411 parameters, 4019 observed reflections
with I 2 3 4 . Several attempts to obtain analytical data were unsuccessfuldue
to fractional loss of toluene from analytical samples. Further details of the
crystal structure investigators are available on request from the Director of the
Cambridge Crystallographic Data Centre, University Chemical Laboratory,
Lensfield Road, GB-Cambridge CBZlEW (UK), on quoting the full journal
Received October 19, 1991 [Z 4980 IE]
German version: Angew. Chem. 1992, 104,466
CAS Registry numbers:
1,139242-93-6; 2,139242-94-7; 2.2C,H8, 139242-95-8;HOCH(CF,),, 920-661; HOC,F,, 771-61-9; BiPh,, 603-33-8.
Y.Tanaka, M. Fukutomi, T. Asane. Jpn. J. Appl. Phys. 1988,
27, L209; b)C. Michel, M. Hervieu, M. M. Borel, A. Grandin, F. Deslandes, J. Provost, B. Raveau, Z . Phys. B-Condensed Matter 1987, 68,421.
a) W J. Evans, J. H. Hain, Jr., and J. W. Ziller, J. Chem. SOC.,Chem. Commun. 1989, 1628; b) M. A. Matchett, M. Y Chiang, W. E. Buhro, Inorg.
Chem. 1990,29, 358.
C. M. Jones, K. H. Whitmire, unpublished.
H. Gilman, J. F. Nelson, J. Am. Chem. Soc. 1937, 59, 935.
K. H. Whitmire, J. C. Hutchison, A. L. McKnight, unpublished.
a) A. Schier, J. M. Wallis, G. Miiller, H. Schmidbaur, Angew. Chem. 1986,
98, 742; Angew. Chem. Int. Ed. Engl. 1986, 25181, 757; b) W. Frank, J.
Weber, E. Fuchs, ibid. 1987, 99, 68 and 1987, 26. 74.
[l] a) H. Maeda,
A Nonaromatic Expanded Porphyrin Derived
from Anthracene-A Macrocycle which
Unexpectedly Binds Anions **
By Jonathan L. Sessler,* Tarak D . Mody, Debra A . Ford,
and Vincent Lynch
Dedicated to Professor James P. Collman
on the occasion of his 60th birthday
Porphyrins are among the most versatile ligands, forming
complexes with almost every metal cation in the periodic
table."] However, little record of these species as anion-binding agents''] has appeared in the 1iterat~re.l~
One reason,
perhaps, is that protonated porphyrins, with a core diameter
[*] Professor J. L. Sessler, T. D. Mody, D. A. Ford, Dr. V. Lynch
Department of Chemistry and Biochemistry
University of Texas at Austin
Austin, TX 78712 (USA)
[**I This work was supported by the National Institues of Health (A1 28845).
J. L. S. also thanks the NSF for a Presidential Young Investigator Award
(1986), the Alfred P. Sloan Foundation for a Research Fellowship (19891991), and the Camille and Henry Dreyfus Foundation for a TeacherScholar Award (1988- 1992). D. A. F. is grateful to the United States Navy
for allowing an academic leave and for providing M. S. thesis support.
Angew. Chem. Int. Ed. Engl. 31 (1992) No. 4
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