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Hydrothermal Synthesis of a Novel Se12 Ring in [{(NH4)2[Mo3S11.72Se1.28]}2[Se12]]

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X-ray resiilts. Refinernenis were carried out by a least-squares procedur-e [bc].
miniiiii~ing1 1 1 (F:- L'b-:)2 using all independent data. Weights were assigned
ii\ 11 = 0 I. uhere 0' = (OF,+ (0.015)fi:)2). The structure model included
ad~u.;tahlepositional kind anisotropic thermal parameters for all 136 iitorns. a
\tale l"ictor k . and ii parameter for an isotropic-type I extinction correction
u i t h Lorenman mosaic spread [6c]. The maximum extinction correction was
lo"<). for I l k (T23) reflection. Neutron scattering lengths were taken irom a
recznl coiiipilAion by Sears [6b]' h, = 0.66484. b,, = - 0.3741, h, = 0.936.
/I,, = 0.511. hKL= 0.920 (all x l o - " crn). Further details of the crystal strucion are available on request from the Director of the Cambridge
Iiic Data Centre. 12 Union Road. GB-Cambridge CB2 IEZ
ling the full journal citation. b) J. DeMeulenaei-, H. To
~ ' i ) . s r d / o g r1965.
/Y. 1014: L. K. Templeton, D. H . Templeton. Am.
y r . ~ W K I. l ~ y, Storrs. C'T Abstract E10. 1973: c) J . 4 . Lundgren.
, y r u p l i i ~( ' o i i i / ) i t i e w Pm,qrfii~i.s
in Report UUIC-Bl3-4-05, Institure of Chemistry.
Iliiivcrsit). ot'IJppsa1,i. Sweden, 1982. d) P. Becker. P. Coppens. Ae,ru Cr)wdbirr S i w .A 1974. 30. 129. i h i d 1975. 3 I . 417: e) V. F. Sears in Iriteriie~tioniil
X r I ) / c , \ / o r ( ' r ~~ / u / / r > g r o p / i Vr ,d . C' (Ed.: A. J. C . Wilson). Kluwer. .4c;ideniic
Puhlishei-h. Dordreclit. 1993.
S. (i K ; ~ ~ ~ i r i ; iPi i ,A . Hamley. M. Poliakoft J. A i r i . C/wir. SIK 1993. 1 1 5 ~
4 069
R H . ('rahlree. Aiigcw (1/1wr7. 1993. 105. 828: Aiigeii. Ciwni. / t i / . Ed. Eiijii.
1993. 32. 7 X c l
T Richard.;(in. S. deG;ila. P. E M . Siegbahn. R. H. Crabtree. J. A m C/irn?
.So, . ~ u h i n i t ~ c d
i i ) C~aiissiaii92 DFT. Revision F.4: M. J. Frisch, G. W. Trucks. H. B. Schlegel,
P. M. W. G i l l , B G. Johnson. M . W. Wong. J. 8 . Foresman. M . A. Robb. M.
Replogle, R Gomperts. J. L Andres. K. Raghovxhari.
inzale,. R. L Martin. D. J. Fox. D. J Deft-ees. J. Baker.
Poplc. Gaussian Inc.. Pittsburgh. PA, 1992 For further
tion see ret'[lOb] b) For Re. a relativistic ECP [IOc] wa.
shell of Re includes the 5s. 51, w t h a basis set of triple
CP of Stevens and Biisch [IOd] was chosen with 'I doubl
riz:ition. Indole was represented by a planar N H ,. The
h y r l i ideb iiic ieprescnted by a triple basi, set with poliiriration and the H of
PH h!
\iiiglc ;basis set. For tlic functional density. we used the hqbrid
luiic'tioii\ o l Bccke (B3LYP) [loel. c ) D. Andrae. U. Hausserrnann. M. Dolg.
H Sroll. ti l%xiss.?liiwr. C ' h h Acrrr 1990. 77. 123: d) W. J. Stevens. H. Bash.
M. Kraus\. ,/ C/wiri. Pii~..\. 1984. I?. 6016. e) A. D. Becks. J. (1Ii~w.P/I).S.1993.
YS. i64X: P I Ste\cns. F. .I. Deblin. C. F. Chablowski. M. J. Frish. ;bid 1994,
YH. I I h l i .
J. K Hurderl. K . Hollmmn. R. C . Fay. /rrorg CIiiw71 1978. 17. 2553.
J M Manriclue/, D. R. McAlistei-. R. D. Sanner. J. E. Bercaw. J A I I I .C ~ P I I I .
1978. 100. 2716: flljd. 1976. 98. 6733.
L S Van
Slugs. I . Eckert. 0 . Eisenstein. J. H. HAl. J. C. Huffmiin. S. A.
Koctrle. Ci. J Kubas. P. J. Verganini, K. G. Caulton, J A m
<'/wnr. Sor 1990. 112. 4831.
M . ( l-.ttt.i. . 4 < < .( ' / i < ~ . Rcs. 1990. 33. 120.
_I ('h;itl. R 5. ('oft'eg. .I ('II~wI.
So<..4 1969, 1963
'r t.'.
chalcogenide chemistry have yielded several new "polymeric" materials: [Mo,Se,Js-. [Mo,Se,,]' -. [Mo, ,Se,,]" -,
[MO,S,,]~-, and [ M O , S ~ , , ] ~ - . ~I n~ this
- ~ I paper we report the
formation of a novel puckered Set, ring. stabilized by
[Mo,S,,]' - clusters through interchalcogen interactions. This
new form of selenium fits into the Q, sequence [Q = chalcogen)
of homoatomic sulfur ring structures, S,, Slo. S,,, . . . Szo.r5]
Large ring systems of polyselenides and polytellurides have
been examined as parts of metal complexes.[6. For example, it
has been known that selenium and tellurium ions can form
complex rings since the isolation of an S e i + ring in
[Se,][AICI,], .[*I Kanatzidis has found isolated Sef; rings in
(Ph,P),[Se, l ] . These rings comprise two Set- ions and one Se2+
ion and link to form a cluster of corner-sharing "cyclohexanelike" rings of selenium.[91Very recently, Sheldrick reported that
the structure of Cs,Tez, contains a two-dimensional 4, network
of tellurium Tei- ions as well as discrete Te, rings."'
The synthesis of the above-mentioned polychalcogenides has
been achieved through moderate temperature reactions of the
elements with oxidizing agentsc8]-in the case of polyselenide
ions with a mild oxidant["I---or through methanothermal reactions with the elements.'"] We have had some success in preparing large polysulfide clusters by hydrothermal reactions.[4. 'I
and we used this synthetic route to prepare the title compound 1.
The hydrothermal reaction of (NH,),MoS, with A$,
(A = Na, K: .Y = 2-6) generally resulted in the formation of a
new phase of (NH,),[Mo,S
Replacing the polysulfide salt
with A,Se, (A = Na, K ; s = 2-4) yielded primarily selenium
metal, molybdenum metal. and some soluble polychalcogenides. By preparing a new heteropolychalcogenide salt,
Na,S,Se, ,[''I whose redox potential lies between the polysulfide
and poly~elenide,"~.
14] we were able to tune the chemistry of the
redox reaction and isolate compound 1.
The solid-state structure of 1 is shown in Figures 1 and
'I Double layers (AB packing) of trinuclear molybdenum
Richard A. Stevens, Casey C. Raymond, and
Peter K. Dorhout*
Since their discovery!'] the [MO,S,,]~- core clusters have
spurred researchers on to further study. Electron-poor, trinuclear molybdeniim chalcogenides. sulfides in particular. have
aroused considerable interest because of their hydrodesulfurization activity.I2I New ventures into trinuclear molybdenum poly[*I Prof Dr. 1'. K . L h r h o u t , R . A. Stevens. C. C . Raymond
L)ep.irlmeiit 01' ('hemistry. Colorado State University
I-ort Collins. c'o 80523 (USA)
Telet'ix: Int. cude + (303)401-1801
[**I Fin:inci;il hupport w a s provided by the American Chemical Society. Petroleum
Rehcarcli F(itiiidstion. and the Research Corporation, Cottrell Fellowship.
Addilional help provided by C. M Zclenski (EDS). S . M. Miller (X-ray diff raction).
and Di-. H. Murray. Exxon Kescarch. for providing some molyhden u n \tarting iiiLitcriiils.
Fig. 1 Crystal structure of I viewed along the c axis [15]. Only halfthe cell is shown
forclarity. 6 :
N iitoms. 0:
Moatoms. 0 : S a t o m s . 0:
Seatom\ These-Sebonds
within the Se,, ring are nearly all identical: 2.335(2) and 2.327t2) A. The internal
Se-Se-Sc ring angles are consistent with those found for Se, and re8 [?I. alternating
between 105.14(4) and 102.94(7)'. Instead of [Mo,S,, .,Se, ,] the simplified structure of [Mo,S,,] is shown.
were the only sulfur atoms that did not refine satisfactorily. This
is consistent with the relative ease of substitution at this position
of the [Mo,S,]~+ core.f2'] Using a correlated site-occupancy
model,[221we refined the site-occupancy factor of two related
atoms (S and Se) on two different sites. The resulting refinement
yielded a cluster best modeled as formula 2.
The reactivity of our new heteropolychalcogenide anion
S,Se:- in hydrothermal reactions has proven to be unique. Hydrothermal synthesis has yielded a new form of neutral selenium
that is intimately held within a network of molybdenum polychalcogenide clusters and ammonium ions.
Esperirnentul Procedure
Fig. 2. Crystal structure of 1 viewed along the (I axis and showing important Se S
intercluster interactions (dashed lines). Anisotropic thermal ellipsoids are shown:
M o and Se atoms are shaded, S a n d N atoms are principle axis ellipsoids. Selected
chalcogen interaction distances [A]:interactions between clusters from layer A and
clusters from layer B: S2 ~S2.3.207(3);S2 -S3. 3.507(3); interactions between clusters within the same layer: SI . S3. 3.466(3); cluster- ring interactions: SI Set.
3.331(3): S4-Sel. 3 754(3) and 3.492(3): S4-Se2. 3.472(3): S 5 Se2. 3.544(3). Instead of [Mo,S,, :Je, ,] the simplilied structure of[Mo,S, <]IS shown.
The title compound I w a s prepared by combining (NH,),MoS, (0.131 g. 0.5 mmol)
and Na,S,Se, (0.381 g, 1.0 mmol) with 500 UL degassed water in an evacuated.
flame-sealed. fuhed silica ampoule. The reaction was complete under autogenous
pressure at I50 C after 100 11 The resulting solution was filtered. and the sollds
washed with deionized water until the filtrate was colorless. Since diffraction lines
from any other compound were absent from the powder diffraction pattern of the
product solids. the yield was nearly quantitative; selenium m d molybdenum pouders were. howevcr. found. Elemental analysis (EDS) for H,,N,Mo,S,, 4nSei4.ih
[YO]calcd. M o 22.58. S 29.48. Se 45.11; found M o 22.53. S 29.77. Se 44.71.
Received: June 14. 1995 [Z80931E]
German version: A n g m . Choii. 1995. 107, 2737 -2739
Keywords: hydrothermal reactions . molybdenum compounds
polyselenides . polysulfides . selenium rings
clusters of [Mo3S11,,Se, ,J-encircle D,,rings of Se,,. One
type of ammonium cation is located above and below the Se,,
rings, located within the planes of the molybdenum clusters (NI,
Fig. 2). A second ammonium cation (N2) is found centered on
the other threefold axis in the cell, above and below the double
layers. The packing forms a very intricate network of interactions between anionic clusters and neutral Se,, rings (Fig. 2). A
summary of atomic coordinates is found in Table 1.
[ I ] A. Miiller. S. Sarkar. R. G. Bhattacharyya. S. Pohl. M . Dartmann. A n g w .
Chrm. 1978. 90. 564-565: Angew. Chcm.irrc. Ed. €rig/. 1978. 17. 535-536; A.
Miiller. R. G. Bhattacharyya. B. Pfefferkorn. Chem. & r . 1979. 112, 778-780:
A . Muller. S. Pohl. M. Dartmann, J. P. Cohen, J. Bennett. R. M. Kirchner. Z .
Naturforsr~li.B 1979. 34. 434-436.
[2] A. Muller. Po/ihrdron 1986.5. 323- 340. A Miiller. E. Diemann. A . Branding,
F, W. Baumann. M . Breysse. M. Vrin'it. Appl. Curd 1990, 62. L13 L17; A.
Muller. R. Jostes, F. A. Cotton. Angew. Chern. 1980, 92. 921 -929, A n g e ~ .
Chem. I n / . Ed. €ngI. 1980, 19. 875-882.
[3] J.-H. Liao. M . G. Kanatzidis. 1nor.g. ChCwi7. 1992. 31. 431 -439; J Am. C/rem.
Soc. 1990, 112, 7400-7402: J.-H. Liao, J. Li. M. G. Kanatzidis, Inorg. Chwr?.
1995, 31.2658 2670.
Table 1. Atomic coordinates. U(eq) (A' x lo3)),and site-occupancy factors SOF
[4] C. C. Raymond. P. K . Dorhout. S. M . Miller, Inorg. C h e m 1994, 33. 2703 for I.
[5] R. S. Laitinen. P. Pekonen. R. J. Suontamo. Coord. Cher??.Ree. 1994. 130.
[6] M. A. Ansnri. J. A . Ibers. Coord Chem. Rev. 1990. 100. 223-226: M. G.
Kanatzidis, Coriiments Inorg. Chem. 1990. 10. 161 -195
[7] W. S. Sheldrick. M . Wachhold, Angrw Chmi. 1995. 107. 490 491: Angen.
Cherii. I n / . E d ErigI. 1995. 34, 450-451.
[ X I R. K . McMullen, D. J. Prince. J. D. Corbett. Inorg. Choir. 1971, 10. 17490.0572(2)
[Y] M. a. Kanatridis. S:P. Huang. fnorg. Chrm. 1989. 28, 4667- 4669.
0.9295( 14)
0.1 850(4)
[lo] W, S. Sheldrick, H. G. Braunbeck, Z . Nuturfursch. B 1989. 44, 1397-1401.
0.1 123(6)
[ I l l A new polytype of (NH,),[Mo,S,,] has a monoclinic cell: Pm, u = 5.694(2),
h =18.907(7). c = 9.X99(4) A. =106.47(3) .
[I21 Na,S,Se, was prepared from the elements in liquid ammonia. Differential
scanning calorimetry confirmed that this new salt is a single phase with a
congruent melting point of 330 "C. Chemically associated reduction,!oxidation
waves are seen at -0.74 V and -0.17 V vs. SHE.
1131 S. Licht, J € / e c t ~ ~ ~ c A rSot,.
m . 1988, 135. 2971 -2975.
[ 141 S. Licht. F. Forouzan. J. € / m m i ~ l i ~ i S
n i. c . 199.5, 142. 1546 1551.
[15] Crystal structure analysis of a black hexagonal plats of 1: trigonal, P 3 d ,
The neutral Se,, rings are reminiscent of the S,, allotrope of
(I = h =10.207(1). c = 28.351(3) A. V = 2558.0(4) A3, Z = 3 , plalsd= 3.288.
F(000) = 2300, 3673 reflections were collected on a Siemens P4 diffractometer
sulfur.[' Until now, the largest known neutral selenium ring
at 23 'C using Mo,, radiation (0-20 scans. (4.6-50 , 20 range).
systems were only Se, rings"81 and heteropolychalcogenide, np = 12.76 mm- I. semiempirical absorption correction using $-scans). 1496
membered S,Se, rings (where 6 5 12 5 12)
(Of course. gray
unique retlcctions (K,,,= 0.0649.1103.1~201)were used to refine 83 parameselenium exists in the more common, "infinite" chain form.["])
ters. refinement program SHELXL-93.[23] against I F 2 / to R I = 0.0401,
wR2 = 0.0975, and GOF =1.005. Chalcogen atoms Q3 and Q4 were each
Unlike with our previous structure^,'^' ' 1 1 the [MO,Q,,]~refined at two distinct hut correlated positions as Se and S based on appropriportion of 1 (Q = S, Se) did not refine well. It was quite possible
ate bond distances. Further details o f t h e crystal structure investigation may be
that both S f - and Se$- formed during the reaction of MoSZobtained from the Fachinformationszentrum Karlsruhe. D-76344 Eggensteinwith the heteropolychalcogenide salt in aqueous ~ o l u t i o n . ~ ' ~ ]
Leopoldshafen (Germany). on quoting the depository number CSD-59064.
The S3 and S4 atoms that comprise the "paddles" of the cluster
[I61 G. M. Sheldrick. unpublished.
-(2.I . 1 .O)
I .7
- ( 3 0.1.0)
-( 1 . 1 . 1 . 1 )
From Porphyrin Isomers to Octapyrrolic
"Figure Eight" Macrocycles
Emanuel Vogel,* Martin Broring, Jiirgen Fink,
Daniel Rosen. Hans Schmickler, Johann Lex,
Kyle W. K. Chan, Yun-Dong Wu,* Dietmar A.
Plattner, Maja Nendel, and Kendall N. Houk"
113-2lG 19.0
4 3 . 1 .O.O)
-(4 0.0.0)
Fig. 1. Porphyrin and i t s isomers w t h an N, coordinarwn \tic: [lX]pi)i-phyrin( i ? m . p . y ) (1 8 ) . Data below the structural formulaa: value\ or ilie relative energies
(in kcalniol-') calculated by PM3 and BLYP:6-31G** ,3-2l(i
D d i r ~ r r c d10 Prof&ssor Rolf Huisgen
ocmsiori of'liis 7.5111 hirtl7dq
oti l l w
The synthesis of porphycene 2") marks the beginning of a
promising new direction of research in porphyrin chemistry: the
investigation of porphyrin isomers.'21 The formally simple construction principle of 2 involved the reorganization of the structural elements of porphyrin I-- four pyrrole and four methine
units while maintaining the N, coordination site. This principle also led to the assembly of no less than six additional
structural isomers. which contain one or two (as in 2) (Z)-configured C.. CH. .CH...C units (arene fragments).
The structural isomers of [18]porphyrin-(l.1.1.2) resulting
from this operation are depicted in order of increasing energy in
Figure 1 .[.'I Presumably, there are even more candidates than
shown, since the structural isomers of 1 might also occur as ( E )
forms due to the presence of the Cz-CH.--CH-=C group(s).
While the existence of a n ( E j form of 2 can be safely excluded
because of geometrical constraints, ( E ) forms are conceivable in
the cases of the other isomers 3-8. It should be noted that
nonplanar isomers, regardless of their configuration ( E or Z j ,
may adopt chiral conformations, thus offering the possibility of
separation o f enantiomers.
For the synthesis of the porphyrin isomers 3-8, it is useful to
know their energies relative to that of I . These energies, calculated by the UHF:PM3 and BLYP/6-31G**//3-21G i n e t h o d ~ , [ ~ ]
are given i n Figure 1 (in kcalmol-lj for the most stable NH
tautomer. I n each case, this particular tautomer has a diagonal
cl. h l . H r o r i n ~J.. Fink. D. Roscn. Dr. H. Schmickler. Dr. 1. Lex
Chcniie der Universitiit
Grein\tr.i\\c 4. D-50939 Kiiln (Gerinany)
lelefax: Inl. code (221)470-510?
Prof. Dr \ ' - D LVu. K 'A'. K Chnn
Depirtmen I of' ('hcni iulrq
T h e H o n g Kim? ~ J t i i ~ c r of
~ iScicnce
~ y
and Technology
Clear Water HJ). Kov,loon (Hans Kong)
Telefiix: In[ code + 3 % - 1 5 9 4
Prof: [It. K N H o n h . X I . Nendel. Di-. D A. Plattner
Depiirtnieiit 0 1 C'heiiii\tr!. iiiid Biocheniibti-y
University 0 1 C~aliforiiixLos Angelea
Los At~gelc\. ( ,\ 90Oi)5-l5h9(IJSA)
I c l e f : ~ ~I n: i codc + (?IOi20(~1X43
("trans") arrangement of the imino protons as shown in the form u l a ~ . It
[ ~is~ interesting to find that the stability of porphycene
compares favorably with that of porphyrin : depending o n the
computational method employed, either I or 2 is predicted to be
the more stable isomer. Evidently, the slightly strained porphycene is stabilized by the presence ofstrong NH . . . N hydrogen
bonds. [18]Porphyrin-(2.1.1 .O) (3, hemiporphycene) and [18]porphyrin-( (4, corrphycene) are predicted to be only moderately higher in energy. This prognosis is in accord with the observation that the hemiporphycenes[" and corrphycenes"] that have
been synthesized recently have properties similar to porphyrins.
The energies o f the porphyrin isomers 6-8 relative to those of
1-5 increase so drastically that it is doubtful whether these species
will be stable molecules.
These considerations turned our interests to (E)-corrphycene
(10. Scheme 1 ) . Inspection of the Briegleb-Stuart model indicat-
Scheme 1. T h e i . C d ~ e t h y lsuhstituents of the pyrrole rings are omiited [or cliii-ity.
ed that 10 is nearly unstrained but rigid, having the formal double
bond in an orthogonal arrangement with respect to the tetrapyrrolic x system. Semiempirical UHFjPM3 calculations predict
a similar geometry for 10 and an energy 8 kcalmol- above that
of the (Z)-isomer 4.Is1Consequently, 10 is likely to be a chiral. CTZ
symmetric. and nonaromatic porphyrinoid. Porphyrinoid 10 can
possibly be synthesized by dehydrogenation of dihydrocorrphycene 9. According to models, the dihydro compound 9 has a
conformation similar to that of 10 with the CH,CH, group in a
position conducive to the generation of a n ( E ) double bond.
This synthetic strategy fell short of the original goal, since
compound 9 never materialized. However. the search was success-
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synthesis, mo3s11, se12, nh4, 72se1, hydrothermal, ring, novem
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