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Cs2Bi10Ca6Cl12O16 A New Type of Catalyst for Selective Oxidation Derived from Bismuth Oxychloride.

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equatorial), 3.60 (m, ZH, CH-O), 3.30 (m, I H, C H - 0 ) , 3.15 (m, 1 H,
CH:-O,axial), 3.02(m, I H, CH-O), 2.75, 2.52(2xm, 2x0.5H, CH), 2.301.40(m, IOH,CH,), 1.25, 1 . 1 2 ( 2 x d , J = 7 . 4 H z , 2 ~ 1 . 5 H , C H - C H , ) , I.O(m,
3 H, CH?-CH?), 0.88 (m, 2 H, CH2-SiMe,), 0.0 (s,9H, SiMe,); HRMS, calcd
for ClxH3,O3Si( M a ) 326.2285, found 326.2284.
5 a : The didehydrooxepane system 4a (326 mg, 1.0 mmol) in anhydrous T H F
( 5 mL) was treated under argon with nBuaNF (1.0 M solution in THF,
1.2 mL, 1.2 mmol) at ambient temperature and then stirred at 45°C for 8 h.
Removal of the solvent, followed by flash column chromatography (silica,
20% ether in petroleurn ether) gave 5a (215 mg, 95%). 5 a : oil, R,.=0.30 (silica, 20% in petroleum ether); IR (neat), V,.,,=2940, 2880, 1720 ( s , ketone),
1475, 1160, 1000,955 c m - ' : ' H NMR (500 MHz, [D6]benzene), 6=3.90 (dd,
J=9.4, 3.6 Hz, I H, CH-O), 3.70 (m, I H, C H - 0 , equatorial), 3.25 (m, I H,
CH-O), 3.20 (m, 1 H, C H 2 - 0 , axial), 3.01 (m, I H, CH), 2.80 (m. I H,
CH-O),2.05-1.45(m, 10H,CH2),I.22(d,J=7.4Hz,3H,CH-CH3), 1.05(t,
J=7.3 Hz,3H,CH,-CH,); "C NMR(125 MHz,CDCI,),6=217.60(C=O),
86.95, 80.82, 80.47, 67.52, 38.79, 37.72, 35.17, 30.92, 25.66, 12.65, 16.33, 13.68;
HRMS, calcd for C11H2201( M e ) 226.1569, found 226.1567.
Received: June 7, 1988 (2 2808 IE]
German version: Angew. Chem. 100 (1988) 1413
[ I ] For some recent and excellent reviews, see: D. J. Faulkner, Nat. Prod.
Rep. 3 (1986) I : J (1984) 251.
121 Y . Y . Lin, M. Risk, M. S. Ray, J. Clardy, J. Golik, J. C. James, K.
Nakanishi, J. Am. Chem. Sot. 103 (1981) 6773.
[3] For some examples of oxepane synthesis, see: a) K. C. Nicolaou, D. G.
McGarry, P. K. Somers, C. A. Veale, G. T. Furst, J. Am. Chem. Soc. 109
(1987) 2504: b) L. Coppi, A. Ricci, M. Taddei, J. Org. Chem. 53 (1988)
91 I : c) R. Whitby, C. Yeates, P. Kocienski, G. Costello, J. Chem. Soc.
Chenr. Commun. 1987. 429; d) W. T. Brady, Y . F. Giang, L. Weng, M. M.
Dad, J. Org. Chem. 52 (1987) 2216; e) L. E. Overman, T. A. Blumenkopf,
A. Castaneda, A. S. Thompson, J. Am. Chem. Sac. 108 (1986) 3516; f) L.
E. Overman, A. Castaneda, T. A. Blumenkopf, ibid. 108 (1986) 1303; g) P.
A. Bartlett, P. C. Ting, J. Org. Chem. 51 (1986) 2230; h) A. P. Kozikowski,
A. K. Ghosh, ihid. 50 (1985) 3017; i) C. N. Barry, S. A. Evans, Jr., ibid. 46
(1981) 3361: j) K. C. Nicolaou, D. A. Claremon, W. E. Barnette, J . Am.
Chem. Soc. 102 (1980) 6611; k) W. H. Rastetter, ibid. 98 (1976) 6350.
[4] For precedents for such couplings, see: a) K. C. Nicolaou, C.-K. Hwang,
M. E. Duggan, P. J. Carroll, J. Am. Chem. SOC.109 (1987) 3801; b) R.
Jahn, V. Schmidt, Chem. Ber. 108 (1975) 630; c) N. Ishibe, M. Odani, K.
Teramurd, J . Chem. Soc. Chem. Commun 1970, 371.
[S] This and the other dithionoesters shown in Table I were synthesized by
thionation of the corresponding diesters using the Lawesson reagent.
161 All new compounds exhibited satisfactory spectral and exact mass data.
[7] Selected properties of compounds 5 . 5b: RI=0.30 (silica, 30°h ether in
petroleum ether); IR (neat), V,,, 1718 c m - ' ( G O ) ; ' H NMR(5OO MHz,
CDCI,), 6=3.83 (m. I H, C H - 0 , equatorial), 3.79 (dd, J s 9 . 6 , 3.4 Hz,
I H , CH-O), 3.30 (m, 2H, CH-0, CH2-O), 2.90 (m, 2 H , C H - 0 ,
CH2-C(0)), 2.35-1.50 (m, 11H, CH2), 0.90 (t. J = 7 . 3 Hz, 3H,
CH2-CH3). 5 c : R,=0.30 (silica, ether); 1R (neat), =,S,,
1715 c m - '
( C z O ) ; ' H N M R (500 MHz, CDCI,), 6=3.84 (dd, 3=9.2, 3.5 Hz, 1 H,
CH-O), 3.80 (m, I H , CH2-0, equatorial), 3.55 (m, 2H, C H - 0 ,
CH2-O), 3.42 (dd, J=8.0, 3.2 Hz, I H, CH-0), 3.05 (m, 1 H, CH), 2.85
(m, I H, CH-0), 2.10-1.30 (m, 14H, CH,), 1.15 (s, 3H, CH,), 1.05 (d,
J=7.5 Hz, 3H, CHCH,), 3.32 (m, 2 H , CH,-0). 5d: RF=0.5 (silica, 30°/o
EtOAc in benzene); IR (neat), S,,=
1712 c m - ' (C=O); 'H N M R (250
MHz, CDCI,), 6=3.82 (m, 2H, CH2-0, CH-0), 3.60-3.00 (m, 7 H ,
CH2-0, C H - 0 , CH), 3.48, 3.42 (s, 3 H each, OCH3), 2.35-1.50 (m. 10 H,
CH2), 1.20 (s, 3 H, CH,), 1.05 (d, J z 7 . 4 Hz, 3 H, CHCH,), 0.90 (t, J=7.3
Hz, 3 H, CH2-CH,). 5 e : RI =0.25 (silica, 60% ether in petroleum ether);
c m - ' (C=O); 'H NMR (500 MHz, CDCI,),
IR (neat), 5,,,=1725
6=7.50-7.20 (m, 5 H , aromatic), 4.50 (s, 2 H , benzylic), 3.75 (dd, J=9.4,
3.7 Hz, 1 H, CH-0), 3.55-2.70 (m, 9 H , C H - 0 , CH2-0). 3.40, 3.35 (s,
3 H each, OCH,), 2.35-1.40 (m, 14H, CH2), 1.15 (s, 3H, CH,). 5f:
R , =0.60 (silica, ether); IR (neat), =,S
,,
1716 c m - ' (C=O); ' H NMR
(500 MHz, CDCI,), 6=4.62,4.52 (d, J= 11.5 Hz, 1 H each, benzylic), 4.54,
4.38 (d, J = 12.0 Hz, 2H, benzylic), 3.80 (m, 1 H, CH-0), 3.70-3.00 (m,
llH,CH-O,CH2-O,CH),2.30-1.50(m,
14H,CH2), 1.15(s,3H,CH3),
1.09 (s, 3 H , CH,), 1.05 (d, J=7.3 Hz, 3 H , CH-CH,): I3C N M R (125
MHz, CDCII), 6=216.96, 138.04, 137.92, 128.37, 128.37, 128.30, 128.30,
128.27, 127.77, 127.77, 127.73, 127.73, 127.47, 87.73, 81.40, 77.97, 77.74,
75.97, 73.38, 73.11, 72.56, 72.36, 71.6, 71.03, 69.66, 60.54, 44.62, 38.54,
37.96, 34.06, 30.22, 29.66, 27.64, 26.51, 24.08, 16.36, 15.27.
[8] Irradiation o f H, (structure 5a, Table 1) produced a 17% NOE indicating
a syn relationship for H, and Hb Molecular models of 5a suggest a pseudoequatorial position for the Me group as depicted in 5a (rather than the
opposite stereochemistry which forces the Me into a pseudoaxial orientation); MM2 calculations (MacroModel) of the energies give 40.05 kJ
mol-' for 5a and 42.99 kJ mol-' for its epimer, also pointing to the assigned stereochemistry.
1364
0 VCH Verlagsgesellschaft mbH. 0-6940 Weinheim. 1988
CS2BiloCa6C112016:
A New Type of Catalyst for Selective Oxidation
Derived from Bismuth Oxychloride**
By Kenneth D. M . Harris, Wataru Ueda,
John M . n o m a s , * and Gallienus W. Smith
When a 1 : I : 1 : 2 mixture of Bi203, BiOCI, CsCl and
CaC12 is heated for 12 h in an open alumina or platinum
container at 1073 K a new type of compound is formed.
The predominant crystalline product contains single crystals suitable for structural analysis using conventional Xray diffractometric techniques. This product (idealized formula Cs2BiloCa6C112016)
possesses attractive properties as
a catalyst for the selective oxidation of methane in O2
(CH, :O2= 2 : 1, partial pressure of CH, 20 kPa, total flow
rate 50 mL m - ' with N2 as diluent up to atmospheric pressure in the temperature range 873 to 1023 K).
A typical run at 994 K results in 21.3 and 46.3 percent
conversion of CH4 and O2 respectively, and the following
product selectivities: C2H4, 39.5; CzH6, 11.6; C3 and c,
compounds, 3.5 and 3.9, respectively; CO, 7.6; C 0 2 ,
25.0%; with CZ&/C& = 3.4. Further details of the catalytic performance of this and of related materials will be
given elsewhere."]
As with other"] complex layered oxyhalides derived
from or related to the Sillen structurec2](for example,
NaBi30,CI2 and Ca, 2sBils02C13),the mechanism of catalytic selective oxidation is unclear, but likely to i n v o l ~ e [ ~ - ~ ]
methyl radicals.
The structure@]of C S ~ B ~ , ~ C ~ ~isCquite
I , ~novel
O , ~ (Fig.
1, Table 1) and exhibits interesting features including the
presence of a layer which is itself structurally similar to
that in CsCl with the alkali cation, as expected, in eightfold coordination. Within this layer, however, there are
two types of Cs site (designated Csl and C S ~ )both
,
of
which are only partially occupied, with fractional occupancies of 0.78 and 0.21 respectively. This layer is flanked
on either side by layers of modified BiOCl with Bi3@and
Ca2@ions occupying the same sites (subsequently designated M sites). In the crystal structure refinement, the ratio
of Bi3@and C a 2 @on these sites has been allowed to vary
subject to the constraint that the total occupancy on each
M site is
The fact that the fractional occupancies
of Bi3@and Ca2@are not 0.625 (10/16) and 0.375 (6/16)
respectively for each of the M sites indicates that the Bi3@
and CaZe cations, whilst capable of occupying the same
type of site, are not distributed at random in the modified
BiOCl layers. (We note, in passing, that a tendency for
non-random, supermesh arrangements involving Bi3' and
Ca2@cations within layers of the warm superconducting
compounds[8-'01 of Bi/Ca/Sr/Cu/O (suggested formulas1'i.121Bi2Sr2-xCaCu208 and Bi2+.Ca, -,SrzCu2O8+J
[*I Prof. Dr. J. M. Thomas, K. D. M. Harris [+I, Dr.
W. Ueda ["I
Davy Faraday Research Laboratory, The Royal Institution
21. Albemarle Street, London WIX 4BS (UK)
Also at Department of Physical Chemistry,
['I
University of Cambridge
Lensfield Road, Cambridge CB2 IEP (UK)
[' '1 Permanent address: Tokyo Institute of Technology
4259 Nagatsuta, Midori-ku, Yokohama 227 (Japan)
Dr. G. W. Smith
I , West Farm Avenue
Ashtead, Surrey KT21 2LD (UK)
[**I This work was supported by the Science and Engineering Research
Council, The Ramsay Memorial Trust (who awarded a Japanese Ramsay Fellowship to W. U.) and by BP (through a studentship to K. D. M.
H.).
0570-0833/88/1010-1364 $ 02.50/0
Angew. Chem. Int. Ed. Engl. 27 (1988) No. 10
[2] L. G. Sillen, 2. Anorg. Allg. Chem. 242 (1939) 41; 246 (1941) 115.
[3] J. M. Thomas, W. J. Thomas: Introduction to the Principles of Heterogeneous Cutalysis, Academic Press, London 1967, p. 383.
[4] T. Ito, J. H. Lunsford, Nature (London) 314 (1985) 721; J. M. Thomas,
ibid. 314 (1985) 669.
[Sl K. D. Campbell, H. Zhang, J. H. Lunsford, J . Pbps. Chem. 92 (1988)
750.
[6] Crystal structure of Csl 98Bi1u02Cas
Y8C1,20,h:tetragonal, space group
I4/mmm, u=547.71(9), c=3286.2(7) pm,pCllSd=5.53
g cm-',p=463.19
cm-I, F(OOO)= 1393.98. Data collection at room temperature on a
CAD4 diffractometer, MoKnradiation (A=71.069 pm); 1.5"<0<36",
h = -9, k=O to 9, l=O to 54. Numerical absorption correction applied
after indexing crystal faces and using the crystal size (0. I8 x 0. I8 x 0.0 I
mm3) which minimized R,,,,
(0.038) for the merging of equivalent
0 CI
reflections. (For comparison, R,,,,=0.282
with no absorption correction.) Total of 760 unique reflections measured, of which 53 I (satisfying IFI>3o(F)) were used in refinement. Scattering factors for
0 Csl
neutral atoms were assumed. Anisotropic thermal parameters were
used finally for all atoms. R=0.0419, R,, =0.0354 using weight
1.6917/(a2(F)+0.0002~).Salient data (with fractional coordinates
x/u, y/b, z /c ; and occupancies) are given in Table I .
r:: cs 2
17) In a given refinement job, the occupancies of the two types of Cs site
and the relative Bi'"/Ca2" occupancies on the M sites were refined
with the thermal parameters for all of these sites fixed, while, in the
following refinement job, the occupancies were fixed at these new vals o
ues and the thermal parameters allowed to refine. This iterative procedure was continued until constancy of both occupancies and thermal
parameters produced from successive pairs of refinement jobs was ob0
Bi/Ca
tained for all of the Cs and M sites (see K. D. M. Harris, Ph. D. Thesic
(1988), University of Cambridge, for further details).
[8] C. Michel, B. Raveai, 2. Phys. 868 (1987) 421.
191 A. H. Maeda, Y. Tanaka, N. Fukutomi, T. Asamo, Jap. J. Appl. Phps. 27
(1988) 2.
[lo] M. A. Subramanian, C. C. Torardi, J. C. Calabrese, J. Gopalakrishnan,
Fig. I . Two representations of the stacking of the constituent ions in the
K. J. Morrissey, T. R. Askew, R. 8 . Flippen. U. Chowdhry, A. W.
(In b, conventional
structure of the oxidation catalyst Cs2Bi10Ca6Cl12016.
Sleight, Science lWushinglon. DC)239 (1988) 1015.
ionic radii are represented.) In the layers of modified BiOCl which are inte[1 I] A. K. Cheetham, A. M. Chippindale, S. J. Hibble, Nature (London) 333
gral parts of this novel structure the Bi'"and Ca2" cations share the same
(1988) 21.
sites but not completely at random (see text). Note also the existence of two
[I21 W. Zhou, D. A. Jefferson, private communication; see also E. A. Hewat,
different types of Cs site within the CsCl layers. In both of these sites the Cs
P. Bordet, J. J. Capponi, C. Chaillout, J. L. Hodlan, M. Marezio, Nulure
is in eight-fold coordination.
(London) 333 (1988) 53.
[I31 Briefly, the validity of the refined occupancies of Cs, Bi and Ca is supTable 1. Fractional coordinates and site occupancies in C S ~ B ~ , ~ C ~ , C I , , O , ~
ported by the three following facts. First, crystal structure refinements
(with estimated standard deviations in parentheses).
starting from different initial sets of occupancies produce, in all cases,
the values given in Table 1, within the quoted standard deviations. Secx/u
v/b
Z/C
Site occuSites [a] Wyckoff
ond, from the stoichiometry that follows from these occupancies (i.e.
PancY
notation
Cs, sXBi,ou2Ca,,*C1120,h)
the net charge is 0.00, indicating that, within
errors, this stoichiometry satisfies the requirement of electro-neutrality.
2
U
0
0.78(1)
0
Csl 0
Refinements in which the total occupancy of individual M sites are
0.21 l(8)
2
b
1/2
0
cs2 1/2
fixed at values less than unity (e-g. 0.95 or 0.90), while the Bi"/Ca'@
0.0722(1) I
0
CII 112
8
9
ratio for these sites is allowed to refine, lead to stoichiometries for which
M1 0
0
0.1222(1) 0.70(1) (Bi)
4
e
the net charge is distinctly non-zero, thus vindicating our assumption
0.3011) (Ca)
that the total occupancy of each of the M sites is unity. Third. the bond
M2 1/2
1/2
0.1187(1) 0.206(6) (Bi)
4
e
valence sum (S) for the oxygen site in the structure, when computed
0.794(6) (Ca)
using the parameters R:", Nc,,, R?', NB,(compiled by 1. D Brown, K. K.
0
0.248419) 0.2484(9) 0.1574(2) 1
16
m
Wu, Acta Crystallogr. Sect. 8 3 2 (1976) 1957) yields a value of S=2.04
M 3 1/2
0
0.1907(0) 0.80(1) (Bi)
8
9
(theoretical value 2.00). Here
0.20(1) (Ca)
4
e
c12 0
0
0.2499(5) 1
[a] Number of sites in the unit cell.
has recently been postulated by Zhou et aLf1*IIndeed, from
the magnitude of the thermal parameter quoted by Subrurnaniun et al.['O1for the Bi3@site in their 'warm' superconductor one may suspect that, in that material also, both
Bi3@and C a Z Gmay tend to occupy this site.)
The new structure reported here (for CS2Bi10Ca6C112016)
is corroborated by other evidence.['31It is not far removed,
architecturally, from the rich variety of discrete structures
in the so-called 'Bipox' series['41formed from unit-celllevel inter growth^"^^ of Aurivillius phases"61 and Sillen
phases.
Received: May 30, 1988 [Z 2791 IE]
German version: Angew. Chem 100 (1988) 1415
[11 a) W. Ueda, J. M. Thomas, 9th Int. Congr. on Cuta[ysis, Calgary, June
1988, Paper 123; b) W. Ueda, J. M. Thomas, J. Chem. SOC.Chem. Commun 1988. 1148.
Angew. Chem. In! Ed. Engl. 27 (1988) No. 10
wherefc, andf,, are the fractional occupancies of Ca2' and Bi'" o n the
M site and RM--Ois the M - 0 interatomic distance.
[I41 J . F. Ackerman, Muter. Res. Bull. 17 (1982) 883.
1151 C. N. R. Rao, J. M. Thomas, Accnts. Chem. Res. 18 (1985) 113.
1161 B. Aurivillius, Ark. Kemi 1 (1950) 463, 499.
Solid-Phase Synthesis of 0-Glycopeptide Sequences
By Hans Paulsen,* Gunnar Merz, and Udo Weichert
Glycoproteins are of great interest owing to their numerous biological functions on cell surfaces and as enzymes,
serum proteins, and mucins."' Glycopeptides, containing a
[*I Prof. Dr. H. Paulsen, Dip1:Chem. G. Merz, DipLChem. U. Weichert
Institut fur Organische Chemie der Universitat
Martin-Luther-King-Platz 6 , D-2000 Hamburg 13 (FRG)
0 VCH Verlugsgesellschuft mbH, D-6940 Weinheim. 1988
0570-0833/88/1010-1365 $ 02.50/0
1365
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oxidation, bismuth, cs2bi10ca6cl12o16, selective, typed, derived, oxychloride, new, catalyst
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