The synthesis and structural characterization of a novel Bi-Mo double cubane cluster coupled by two bridging oxygen atoms { [Mo3 (BiI3)OS3 (μ-OAc)2 (py)3]2 (μ-O)2}·2 (H2O)

Article abstract of DOI:10.1016/S0277-5387(98)00296-4

With [Mo₃ (μ₃-O) (μ-S)₃ (μ-OAc)₂ (dtp)₂ (py)] (dtp=S₂P(OC₂H₅)₂)^-; OAc=OOCCH ^-₃; py=C₅H₅N) as the starting material, the reaction together with BiI₃ in presence of (H₂O) results in a novel Bi-Mo double-cubane cluster coupled by two bridging oxygen atoms { [Mo₃ (BiI₃) (μ₃-O) (μ₃-S)₃ (μ-OAc)₂ (py)₃]₂ (μ-O)₂}·2 (H₂O) 2. The cluster 2 has been characterized by IR, Raman, UV-Vis, NMR and single-crystal X-ray study. A comparison is made between these results and those of the previously reported single cubane Bi-Mo cluster [Mo₃ (BiI₃) (μ₃-S)₄ (μ-OAc) (dtp)₃ (py)] 1.

Full text of DOI:10.1016/S0277-5387(98)00296-4

\
PERGAMON
Polyhedron 07 "0888# 170Ð176
The synthesis and structural characterization of a novel BiÐMo
double cubane cluster coupled by two bridging oxygen atoms
"
ðMo "BiI #OS "m!OAc# "py# Ł "m!O# #=1"H O#
2
2
2
1
2 1
1
1
0
Shao!Fang Luꢀ\ Jian!Quan Huang \ Qiang!Jin Wu\ Xiao!Ying Huang\ Da!Xu Wu\ Yu
Zheng\ Rong!Min Yu
State Key Laboratory of Structural Chemistry\ Fujian Institute of Research on the Structure of Matter\ Chinese Academy of Sciences\ Fuzhou\
Fujian 249991\ People|s Republic of China
Received 20 March 0887^ accepted 15 July 0887
Abstract
With ðMo "m !O#"m!S# "m!OAc# "dtp# "py#Ł"dtpꢁS P"OC H # # ^ OAcꢁOOCCH ^ pyꢁC H N# as the starting material\ the
−
−
2
2
2
1
1
1
1
4
1
2
4
4
reaction together with BiI in presence of "H O# results in a novel BiÐMo double!cubane cluster coupled by two bridging oxygen
2
1
atoms "ðMo "BiI #"m !O#"m !S# "m!OAc# "py# Ł "m!O# #=1"H O# 1[ The cluster 1 has been characterized by IR\ Raman\ UVÐVis\ NMR
2
2
2
2
2
1
2 1
1
1
and single!crystal X!ray study[ A comparison is made between these results and those of the previously reported single cubane BiÐ
Mo cluster ðMo "BiI #"m !S# "m!OAc#"dtp# "py#Ł 0[ Þ 0888 Elsevier Science Ltd[ All rights reserved[
2
2
2
3
2
Keywords] MoÐBiÐS"O# double cubane cluster^ Synthesis^ Crystal structure^ Spectrum
0[ Introduction
crystal structure of a BiÐMoÐS cluster is reported only
by us\ i[e[ the single cubane cluster ðMo "BiI #S "m!OAc#
2
2
3
1−
−
In our systematic investigation of the designed syn!
"dtp# "py#Ł 0 "dtpꢁS P"OC H # ^ OAcꢁOOCCH 2^
2
1
1
4
thesis and structural chemistry of the hybrid Mo"W#!
pyꢁC H N# ð01Ł[ Furthermore\ a novel BiÐMoÐS"O#
cluster i[e[ a double cubane cluster 1 has been syn!
4
4
3
¦
main group metal clusters using ðMo "m !Y#S Ł "YꢁO\
2
2
2
S# as the starting materials in organic solvent media\
the MoÐBi clusters have naturally attracted our great
interest[ Bismuth is called a semimetal ð0Ł and is an impor!
tant component in many new functional materials ð1Ð3Ł[
Moreover\ its role in biochemical processes ð4Ł\ medicine
ð5\ 6Ł and catalysis has received more and more attention[
Some early reports have been seen on the BiÐMo com!
posite oxide\ which can act as a highly e.cient catalyst
in the reaction of ole_nes ð7Ł[ So far\ however\ the reports
concerning the structural chemistry of the BiÐMo cluster
compounds are few[ Only after the eighties\ a number
thesized[ In this paper\ the synthesis and the structural
characterization of
a
novel BiÐMoÐS"O# cluster
are
"ðMo "BiI #OS "m!OAc# "py# Ł "m!O# #"1H O#
1
2
2
2
1
2 1
1
1
described[ This is the _rst example of the double cubane
BiÐMo cluster coupled by two bridging oxygen atoms[
1[ Experimental
All the reactions were carried out under the atmosphere
with the CP or AR grade reagents[ IR spectra were rec!
orded on a Nicolet Magna 649 FT!IR spectrometer with
1
of BiÐMo carbonyl!containing compounds e[g[ Bi Mo1
−0
−0
KBr discs "3999Ð599 cm # and CsI discs "599Ð099 cm #[
The Raman spectra were collected on a 809 laser Raman
FT Spectrometer with SP grade KBr as the diluent for
the sample[ The UVÐVis spectra were measured by a
"
C H Me# "CO# ð8Ł\ "Et N# ðBiMo "CO# "m!OMe# Ł ð09Ł
4
3
1
1
3
1
3
01
2
have begun to be reported[ As to BiÐMoÐS cluster\ Saysell
et al[\ reported in 0885 the preparation\ solution behavior
and UVÐVis spectra of the sandwich cubane cluster
0
02
Shimadzu UV!2999 spectrometer[ H NMR and
C
7¦
ðMo BiS "H O# Ł \ but no crystal structure of this com!
5
7
1
07
NMR were recorded on a Varian Unit 499 spectrometer[
pound has been reported ð00Ł[ Up to the present\ the
The samples were dissolved in DMSO!d [ The inductively
5
coupled plasma!atomic emission spectrometer "ICP!
AES# method was used to examine the principal metal
elements[
ꢀ
Corresponding author[
0
Invited Professor at the Fuzhou University[
9
166!4276:88:, ! see front matter Þ 0888 Elsevier Science Ltd[ All rights reserved[
PII] S9166!4276 "87#99185!3

1
71
S[!F[ Lu et al[ : Polyhedron 07 "0888# 170Ð176
2
Ä
1
1
[0[ Synthesis
[0[0[ BiI2
are 9[70 and −9[75 e:A \ respectively[ All the calculations
were carried out on a MICRO!VAX2099 computer using
the TEXSAN program ð03Ł[
A mixture of BiCl "2[18 g# and hydriodic acid "09 ml#
The fractional coordinates and equivalent isotropic
thermal parameters for all the nonhydrogen atoms have
been kept as the supplementary material[ The main bond
lengths and angles are shown in Tables 0 and 1 respec!
tively[
2
was stirred for half an hour and then _ltered[ The solid
was washed with EtOH and ether respectively\ resulting
in 2[79 g greyÐblack precipitate for use[
1
[0[1[ "ðMo "BiI #OS "m!OAc# "py# Ł "m!
2
2
2
1
2 1
O# #=1"H O# 1
1
1
0
15 mgðMo OS "m!OAc# "dtp# "py#Ł"9[0 mmol#
ð02Ł
2[ Results and discussion
2
2
1
1
was dissolved in 09 ml CH Cl and 09 ml CH CN[ To the
1
1
2
solution was added fresh but not enough dried
2[0[ Structural features
BiI "89 mg\ 9[04 mmol#[ The resultant solution was stir!
2
red for half an hour and then _ltered[ After 19 days\ the
black crystals were separated and washed with EtOH:pe!
troleum ether to yield 04 mg of the title crystal[ The prin!
cipal elements were proved to be Mo and Bi by ICP!AES[
The structure is composed of neutral double cubane
clusters coupled by two oxygen atoms "ðMo "m !O#"m !
2
2
2
S# "m!OAc# "py# Ł "m!O# # together with crystal waters[
2
1
2 1
1
As shown in Fig[ 0\ the most speci_c feature of this
structure lies in the cluster molecule[ It contains a crys!
tallographic center of inversion and can be viewed as the
coupling of two identical ðMo BiOS Ł {{cubane boxes||
1
1
[1[ X!ray structural characterization
2
2
[1[0[ Crystal data
through two oxygen bridges "O"5##[ The six member ring
ðMo"0#ÐMo"2#ÐO"5#ÐMo"0#ꢀÐMo"2#ꢀÐO"5#ꢀŁ and two
slightly twisted tetragonals ðMo"0#ÐO"0#ÐMo"2#ÐS"1#Ł\
ðMo"0#ꢀÐO"0#ꢀÐMo"2#ꢀÐS"1#ꢀŁ "ꢀ denotes the related
atom by the inversion center# form a cavity with a
dihedral angle of 73> between the six!membered ring and
the tetragonal[ The Mo"0#ÐO"5# and Mo"2#ÐO"5# bond!
C H N O I S Bi Mo \ F[W[ꢁ1647[19\ monoclinic\
27
35
5
03
5
5
1
5
Ä
P1 :n "è03#\ aꢁ02[572"4#\ bꢁ06[928"1#\ cꢁ08[834"1# A\
bꢁ85[77"1#\ Vꢁ2348"0# A \ Zꢁ1\ Dcalꢁ1[537 g cm
0
2
−2
Ä
[
−0
1
[1[1[ m"MoK #ꢀ78[50 cm
a
A black blockish crystal with a dimension of
[064×9[09×9[09 mm was stuck to the end of a glass
Ä
9
lengths of 0[781"7# and 0[789"7# A respectively are strik!
_
ber by neutral jelly and then mounted on an Enraf!
ingly shorter than the normal MoÐO single bond distance
"1[0 A# ð04Ł\ indicating dÐpÐd p multi!center bonding for
Ä
Nonius CAD3 di}ractometer to perform X!ray di}rac!
tion work using graphite!monochromatized MoK radi!
ation "lꢁ9[60962 A#[ The unit cell parameters were
MoÐO"5#ÐMo\ where electrons are delocalized over the
whole double!cubane cluster[
a
Ä
determined and re_ned by a least!squares treatment of
the setting angles of 14 automatically centered re~ections
It is worth while to note that the present structural
type is di}erent from either the corner!shared sandwich
double cube\ e[g[ ð"H O# Mo S SbS Mo "H O# Ł ð05Ł or
"
01[92>³u³01[81>#[ The intensity data were collected by
using vÐ1u scan mode in the range of 0>³u³14>"h\ 9:
5^ k\ 9:19^ l\ −06:06#[ A variable scan speed was used
1
8
2
3
3
2
1
8
the edge!linked double cube\ e[g[ ð""H O# Mo
1
8
2
0
S Cu# Ł"pts# =19"H O# ð06Ł[ This structure belongs to the
3
1
7
1
"
"
max[ 3[13>:min# with the scan width of 0[99¦9[24tan u
>#[ The re~ections measured were corrected for Lp e}ects
same type as "ðMo ðPb"dtp# ŁOS "OAc# "py# Ł "O# # ð07Ł
2
1
2
1
2 1
1
reported previously by us and both are similar to the
structure of the FeMo!cofactor active center of nitro!
genase ð08Ł[
and the absorption using C scan technique "T
and
max
T
min\ 0 and 9[4427#[ 5278 independent intensity data were
obtained\ of which 2892 with intensities Iꢀ1s"I# were
used in the structure solution and re_nements[ The struc!
ture was solved by a combination of direct method
Another important feature lies in the heterometallic!
heterobridging ðMo BiOS Ł core for each single cube unit\
2
2
in which BiI combines with "Mo # cluster via three BiÐ
2
2
"MITHRIL# and di}erence Fourier syntheses[ All non!
S bonding[ The "Mo # triangle is capped by a "m !O#[
2
2
hydrogen atoms were re_ned with anisotropic thermal
parameters[ The hydrogen atoms were calculated by
assuming idealized geometries[ Their contributions were
added to the structure factor calculations\ while their
positions not re_ned[ Full matrix least!squares re_ne!
ment was based on F[ The number of re_ned parameters
was 241[ The _nal residuals were Rꢁ9[940 and
Three Mo atoms are coordinated by one "m !O#\ two
2
"m !S# and a terminal "py# ligand in common\ Mo"0# and
2
Mo"2# are further labeled by an oxygen atom of the
"OAc# ligand and the bridging O"5# while Mo"1# by two
oxygen atoms belonging to two respective "OAc# groups[
In this way all the Mo atoms have each completed a
distorted octahedral environment[ Although the nature
of the _fth and sixth coordinated atoms of Mo"0# and
Mo"2# is somewhat di}erent from that of Mo"1#\ three
Mo atoms constitute an approximate equilateral triangle
R ꢁ9[942[ GOF "goodness of _t indicator#ꢁ0[14\ max[
w
shift:error on _nal LS cycle D:sꢁ9[994[ The max[ and
min[ residual densities on a _nal di}erence Fourier map

S[!F[ Lu et al[ : Polyhedron 07 "0888# 170Ð176
172
Table 0
Bond distances "A#
Ä
Bi0Mo"1#
Bi0Mo"2#
Bi0Mo"0#
Mo"0#0Mo"1#
Mo"0#0Mo"2#
Mo"1#0Mo"2#
Bi0S"2#
Bi0S"0#
Bi0S"1#
Bi0I"1#
Bi0I"2#
2[680"0#
2[888"0#
3[906"1#
1[529"1#
1[522"1#
1[528"1#
1[733"3#
1[744"2#
2[906"3#
1[777"1#
1[899"1#
1[890"0#
0[781"7#
0[876"6#
1[196"8#
1[13"0#
Mo"1#0O"3#
Mo"1#0N"1#
Mo"1#0S"0#
Mo"1#0S"2#
Mo"2#0O"5#
Mo"2#0O"0#
Mo"2#0O"4#
Mo"2#0N"2#
Mo"2#0S"1#
Mo"2#0S"2#
O"1#0C"0#
O"2#0C"0#
O"3#0C"2#
O"4#0C"2#
N"0#0C"04#
N"0#0C"00#
N"1#0C"14#
N"1#0C"10#
N"2#0C"24#
N"2#0C"20#
1[020"8#
1[13"0#
1[201"2#
1[214"3#
0[789"7#
0[889"7#
1[191"8#
1[16"0#
1[220"3#
1[281"3#
0[15"1#
0[16"1#
0[18"1#
0[16"1#
0[16"1#
0[18"1#
0[21"1#
0[23"1#
0[29"1#
0[22"1#
Bi0I"0#
Mo"0#0O"5#
i
Mo"0#0O"0#
Mo"0#0O"1#
Mo"0#0N"0#
Mo"0#0S"1#
Mo"0#0S"0#
Mo"1#0O"0#
Mo"1#0O"2#
O"0#0Ow
1[220"3#
1[270"3#
1[990"7#
1[020"8#
2[95"1#
i
Symmetry operator] ] 0!x\ 0!y\ 0!z[
with MoÐMo bond distance of 1[529"1#\ 1[522"1#\
1
ing[ From the calculations of the bonding model for a series
of non planar cluster rings M X "XꢁO\ S\ Cl\ Br# using
Ä
[528"1#A respectively[ It is interesting to note that the
2
2
nitrogen atoms of "py# bound to Mo atoms are always in
the SCCC!EHMO method\ the competitive e}ect between
the dÐd p and dÐp p interaction has been theoretically
interpreted and it seemed to be reasonable ð10Ł[ As for "1#\
it is shown from quantum chemical calculations that the
net negative charge of "m!S# in ðMo OS Ł core is less than
the trans position with respect to "m !O#[ This coordinate
2
pattern is di}erent from that in the single cubane BiÐMo
cluster 0\ where N of "py# is situated cis to "m !S# and the
2
opposite atoms to "m !S# are the S atoms of "dtp#[ This
2
2
2
demonstrates that the m atom always prefers to bind the
that of ðMo S Ł ð11Ł[ This electronic factor seems to be
2
2 3
softer donor atom in the trans position[ This result is in
agreement with that given by Hegetschweiler ð19Ł[ The
BiÐMo distance in the range of 2[680"0#Ð3[906"1# A repre!
bene_cial to BiÐS bonding\ thus leading to the strength!
ening of BiÐS bonds[ Therefore\ the shortening of BiÐS
bonds is bound to make the BiÐI bonds lengthened[ In "2#\
the shortening of MoÐN"py# is obviously related to the
Ä
sents a nonbonding character of BiÐMo bonds[
The di}erence of the structures between clusters 0 and
e}ect caused by the trans position of "m !O#[
2
1
is quite striking[ The cluster 0 reported earlier has a
Finally\ the crystal waters act as the interstitial mol!
ecules and _ll in the vacant positions of the structure[ It
can be seen from the crystal structure analysis that the
ðMo "m !S#"m!S# BiŁ core and one bridging "OAc# whereas
the cubane core of cluster 1 is ðMo "m !O#"m!S# BiŁ and
2
2
2
2
2
2
has two bridging "OAc# ligands[ It is of signi_cance to
compare their important bond distances[ Some di}er!
ences between clusters 1 and 0 are summarized as follows
distance between the oxygen atoms "O # of the crystal
w
water and the "m !O# "O"0## of the double cubane cluster
2
Ä
1 "O ÐO"0## is 2[95"1# A\ which can be regarded as a weak
w
hydrogen bond "O HÐO"0# 048>#[ Many examples of this
w
0
1
2
[ MoÐMo bondlengths are shorter in cluster 1 than
that in cluster 0 "1[523"1# vs 1[621"1## and MoÐ"m!
S#bondlength\ longer "1[234"3# vs 1[205"3##[
feature that "m !O# can be involved in the formation of
2
intermolecular hydrogen bond have been found in "Mo #
2
clusters ð11Ł[
[ BiÐS\ BiÐMo distances are shorter "BiÐS\ 1[894"3# vs
1[881"3#^ BiÐMo\ 2[825"0# vs 3[922"1## while BiÐI
2
2
[1[ Spectroscopic studies
bondlength are longer "1[785"1# vs 1[745"1##[
[ MoÐN"py# distances are signi_cantly shorter"1[14"0#
vs 1[23"0##[
[1[0[ Infrared and raman spectra
In addition to the characteristic absorption peaks of
In "0#\ it can be seen that when "m !S# in cluster 0 is
2
the ligands "dtp#\ "OAc# and "py#\ which can be identi_ed
1
replaced by "m !O# in cluster 1\ the MoÐMo bondings are
strengthened and the MoÐ"m!S# bondings weakened due to
the competition between MoÐMo and Mo!bridging bond!
2
on the basis of the standard spectra ð12Ł\ the most impor!
1
Sadtler Standard Infrared Spectra\ 01 K[

1
73
S[!F[ Lu et al[ : Polyhedron 07 "0888# 170Ð176
Table 1
Bond angles ">#
Mo"1#0Mo"0#0Mo"2#
Mo"0#0Mo"1#0Mo"2#
Mo"0#0Mo"2#0Mo"1#
Mo"1#0Bi0Mo"2#
Mo"1#0Bi0Mo"0#
Mo"2#0Bi0Mo"0#
S"2#0Bi0S"0#
S"2#0Bi0I"1#
S"2#0Bi0I"2#
S"2#0Bi0I"0#
S"2#0Bi0S"1#
S"0#0Bi0S"1#
I"1#0Bi0S"1#
I"2#0Bi0S"1#
I"0#0Bi0S"1#
S"0#0Bi0I"1#
S"0#0Bi0I"2#
S"0#0Bi0I"0#
I"1#0Bi0I"2#
59[06"4#
48[87"3#
48[74"3#
28[37"2#
28[12"2#
27[25"1#
64[1"0#
82[05"7#
053[23"8#
83[82"7#
60[3"0#
O"3#0Mo"1#0S"0#
O"3#0Mo"1#0S"2#
N"1#0Mo"1#0S"0#
N"1#0Mo"1#0S"2#
S"0#0Mo"1#0S"2#
O"5#0Mo"2#0O"0#
O"5#0Mo"2#0O"4#
O"5#0Mo"2#0N"2#
O"5#0Mo"2#0S"1#
O"5#0Mo"2#0S"2#
O"0#0Mo"2#0O"4#
O"3#0Mo"1#0N"1#
O"0#0Mo"2#0N"2#
O"0#0Mo"2#0S"1#
O"0#0Mo"2#0S"2#
O"4#0Mo"2#0S"2#
O"4#0Mo"2#0N"2#
O"4#0Mo"2#0S"1#
N"2#0Mo"2#0S"1#
N"2#0Mo"2#0S"2#
S"1#0Mo"2#0S"2#
Mo"1#0S"0#0Mo"0#
Mo"1#0S"0#0Bi
069[2"2#
76[0"2#
77[0"2#
78[4"2#
86[1"0#
75[4"3#
75[7"2#
79[0"3#
88[9"2#
051[6"2#
79[8"2#
72[2"3#
051[0"3#
093[9"1#
091[8"2#
79[4"1#
75[4"3#
061[5"1#
78[8"2#
76[3"2#
81[8"0#
57[1"0#
82[7"0#
88[7"0#
57[7"0#
85[5"0#
84[8"0#
57[9"0#
82[7"0#
88[1"0#
71[8"2#
71[4"2#
71[7"2#
012[7"7#
010[3"8#
019[8"8#
014"0#
69[5"0#
048[05"7#
83[77"7#
85[64"6#
81[18"7#
82[39"7#
054[79"6#
87[96"5#
87[40"4#
83[05"4#
76[4"2#
76[5"3#
79[6"3#
86[5"2#
052[3"2#
70[0"2#
051[1"3##
093[0"2#
092[0"2#
74[0"3#
061[7"1#
70[4"2#
89[7"2#
74[7"2#
81[2"0#
70[2"3#
I"1#0Bi0I"0#
I"2#0Bi0I"0#
O"5#0Mo"0#0O"0#
O"5#0Mo"0#0O"1#
O"5#0Mo"0#0N"0#
O"5#0Mo"0#0S"1#
O"5#0Mo"0#0S"0#
O"0#0Mo"0#0O"1#
O"0#0Mo"0#0N"0#
O"0#0Mo"0#0S"1#
O"0#0Mo"0#0S"0#
O"1#0Mo"0#0N"0#
O"1#0Mo"0#0S"1#
O"1#0Mo"0#0S"0#
N"0#0Mo"0#0S"1#
N"0#0Mo"0#0S"0#
S"1#0Mo"0#0S"0#
O"0#0Mo"1#0O"2#
O"0#0Mo"1#0O"3#
O"0#0Mo"1#0N"1#
O"0#0Mo"1#0S"0#
O"0#0Mo"1#0S"2#
O"2#0Mo"1#0O"3#
O"2#0Mo"1#0N"1#
O"2#0Mo"1#0S"0#
O"2#0Mo"1#0S"2#
Mo"0#0S"0#0Bi
Mo"0#0S"1#0Mo"2#
Mo"0#0S"1#0Bi
Mo"2#0S"1#0Bi
Mo"1#0S"2#0Mo"2#
Mo"1#0S"2#0Bi
Mo"2#0S"2#0Bi
Mo"0#0O"0#0Mo"2#
Mo"0#0O"0#0Mo"1#
Mo"2#0O"0#0Mo"1#
C"0#0O"1#0Mo"0#
C"0#0O"2#0Mo"1#
C"2#0O"3#0Mo"1#
C"2#0O"4#0Mo"2#
Mo"2#0O"5#0Mo"0#
C"04#0N"0#0Mo"0#
C"00#0N"0#0Mo"0#
C"14#0N"1#0Mo"1#
C"10#0N"1#0Mo"1#
C"24#0N"2#0Mo"2#
C"20#0N"2#0Mo"2#
Ow0H"11#0O"0#
i
71[9"2#
055[5"4#
012"0#
014"0#
011"0#
012"0#
016"0#
006"0#
048
047[7"3#
094[0"1#
094[9"2#
75[3"3#
71[5"3#
77[1"2#
069[2"2#
i
Symmetry operator] ] 0!x\ 0!y\ 0!z[
tant bands related to the cluster core are assigned on
experience as listed in Table 2[ Clearly\ the comparison
of the spectra has given further support for the di}erence
of bondlengths between clusters 1 and 0 obtained from
the X!ray structural analysis[ In general\ the shorter the
bond distance\ the higher the vibration frequency and
vice versa[
bridging "OAc#\ e[g[ cluster 1\ the IR spectra has a very
−0
distinctive band at 606 cm [ Besides\ a very intense BiÐI
band "ð16Ł\ p[ 730# has been observed in both the Far IR
and Raman spectra[
2[1[1[ Electronic absorption spectra
It is noteworthy to point out that the n
vibration
Figure 1 shows the UVÐVis spectra in CH
1
Cl [ Because
1
Mo−"m O#
2
can serve as a {{_ngerprint|| for the clusters with one or
two bridging "OAc# ligands[ For clusters with one bridging
of the limited amount of the sample\ no molar extinction
coe.cients o have been provided[ The spectra exhibit
intense absorptions at 139 nm\ 154 nm\ 261 nm and
"
OAc#\ e[g[ cluster 0\ the characteristic band of n
is
Mo−"m O#
2
−0
found to be ca[ 584 cm ð14Ł while for clusters with two
397 nm\ which may be characteristic of "m !O#ÐMo\ "m!
2

S[!F[ Lu et al[ : Polyhedron 07 "0888# 170Ð176
174
2 2 2 1 2 1 1
Fig[ 0[ structure of the double cubane cluster "ðMo "BiI #OS "m!OAc# "py# Ł "m!O# #[
Table 2
The main vibrational peaks "cm # and their assignments
1
]0]1 with d 7[46\ 6[67 and 6[27 ppm respectively\ indi!
!0
cating that the six py|s in the double cubane cluster mol!
ecule are equivalent[ Two signals with d 1[99 and
Cluster 0
Cluster 1
Ref[
0[89 ppm "0]0 ratio# are attributed to the methyl protons
Middle IR
n
n
n
n
n
Mo!"m !Y#
340 "YꢁS#
362
525
561
606 "YꢁO# ð13Ł
of OAc groups[ This indicates that there are two non!
2
02
Mo!"m!S#
Mo!O"OAc#
Mo!N"py#
Mo!Ob
342
531
566
651
ð13Ł
ð14Ł
ð14Ł
ð15Ł
equivalent OAc groups[ On the other hand\ in C NMR
spectra\ three signals have been seen with d 049[09\ 025[56
and 013[35 ppm respectively clearly assigned to the py
ligands[ The other two sets of signals with d 061[94\
"as#
"as#
Far IR
Raman
d
d
Mo!Ob!Mo"as#
Mo!Ob!Mo"s#
340
213
ð15Ł
ð15Ł
0
51[75 ppm and 12[83\ 10[55 ppm are due to the carbon
−
resonances of COO and methyl of OAc groups respec!
tively[ These results are consistent with the molecular
structure determined by X!ray crystallography[
Mo!S"dtp#
Bi!S
Bi!I
Mo!O"OAc# 301
Bi!S
294
080
032
ð11Ł
086
026
310
109
029
124
ð16Ł
ð16\ p[ 730Ł
ð14Ł
ð16Ł
ð16\ p[ 730Ł
ð14Ł
087
031
104
Bi!I
Mo!Mo
3[ Some comments on the syntheses
Some time ago\ we accomplished successfully the _rst
synthesis of a BiÐMoÐS cluster\ i[e[
ðMo S "m−OAc#×"dtp# "py#Ł¦BiI :ðMo "BiI #S "m
2
3
2
2
2
2
3
S#ÐMo\ and ðm!O"5#ŁÐMo charge!transfer"LMCT# based
on the related tentative assignment ð17\ 18Ł[ The broad
band found at 614 nm must be associated with the incor!
−
OAc#"dtp# "py#Ł 0 "0#
2
The molecular structure of cluster 0 indicates the simple
poration of BiI since the corresponding band is absent
2
3
¦
combination of ðMo S Ł with BiI via ð2¦0Ł mode to
in the spectra of the starting "Mo # clusters ð29Ł[
2
3
2
2
6¦
form the cubane!like ðMo BiS Ł cluster core[ On this
basis\ we designed to use "m !O#!containing ðMo OS Ł
2
3
0
02
3¦
2
[1[2[ H NMR and C NMR
2
2
2
Three resonances of the protons of pyridine groups
have been seen from the H NMR spectra in a ratio of
cluster to react with BiI at an attempt to yield the het!
2
0
6¦
erometallic!heterobridging ðMo BiOS Ł
core[ The
2
2

1
75
S[!F[ Lu et al[ : Polyhedron 07 "0888# 170Ð176
1 1
Fig[ 1[ UV!Vis spectrum for cluster 1 in CH Cl solution[
unexpected result is\ however\ a new structural type of
double cubane BiÐMo cluster coupled by two oxygen
atoms[ The reaction course is shown as follows]
Mo "m −O#"m−S# "m−OAc# "dtp# "py#¦BiI "H O#:
2
2
2
1
1
2
1
2
"
ðMo "BiI #OS "m−OAc# "py# Ł "m−O# #=1"H O#
2
2
2
1
1
2 1
1
1
Obviously the participation of "H O# in this reaction
1
causes the two terminal "dtp# of the starting cluster 2 to
be substituted by "H O#[ At the same time\ each Mo
1
atom is coordinated by one "py# ligand to meet the steric
requirement[ The local transformation of the structure
can be shown as follows]
3
¦
It can be seen that each ðMo OS Ł cluster core adds
2
6
2
¦
one BiI to form a ðMo BiOS Ł cubane core whereas
the two ðMo BiOS Ł cores are coupled by two oxygen
2
2
2
6
¦
2
2
atoms _nally to form the title compound\ i[e[ a double
cubane cluster 1[ Here\ the "H O# may come from the
1
undried BiI in the preparation of BiI by the reaction of
2
2
hydriodic acid with BiCl [ The source of "py# is\ however\
2
not yet known[ It is inferred that it might come from the
rupted during the reaction and when it is rearranged\ it
leads to low yield of cluster 1[ Recently\ attempts have
been made to add one drop of hydriodic acid to the
starting material\ the ðMo OS "m!OAc# "dtp# "py#Ł 2[ A
2
2
1
1
plausible mechanism can be that part of cluster 2 is dis!

S[!F[ Lu et al[ : Polyhedron 07 "0888# 170Ð176
176
ð4Ł Yachmirsky KB[ Introduction to Bioinorganic Chemistry\ Nau!
kova Dumka\ Kiev\ 0865 "in Russian#
ð5Ł Herrmann WA\ Herdtweck E\ Pajdla L[ Inorg[ Chem[
reaction of "Mo # with BiI and the resulting solution has
2
2
been heated to boil for 09 min[ 24 mg of the title cluster
have been obtained "29) yield#[
0
880^29]1476[
ð6Ł Asato E\ Driessen WL\ de Grauf RAG\ Halsbergen FB\ Reedijk
J[ Inorg[ Chem[ 0880^29]3169[
ð7Ł Ueda W\ Moro!oka Y\ Ikawa T\ Matsuura I[ Chem[ Lett[\ 0871\
4
[ Conclusions
0
254[
ð8Ł Clegg W\ Compton NA\ Errington RJ\ Norman NL[ Polyhedron
877^6]1128[
In this work\ the cluster "ðMo "BiI #"m !O# "m !S# "m!
2
2
2
2
2
0
OAc# "py# Ł "m!O# #=1"H O# 1 represents the _rst example
of BiÐMo double cubane coupled by two bridging oxygen
atoms[ The synthetic route indicates that\ the par!
ð09Ł Shieh M\ Mia F!D\ Peng S!M\ Lee G!H[ Inorg[ Chem[
0882^21]1674[
ð00Ł Saysell DM\ Sykes AG[ Inorg[ Chem[ 0885^24]4425[
ð01Ł Lu S!F\ Huang J!Q\ Wu Q!J\ Huang X!Y\ Yu R!M\ Zheng Y\ Wu
D!X[ Inorg[ Chim[ Acta 0886^150]190[
1
2 1
1
1
ticipation of "H O# and the substitution of two terminal
1
"
dtp# ligands belonging to the starting "Mo # cluster
2
ð02Ł Lu S!F\ Huang J!Q\ Huang Z!X\ Zhang B\ Huang J!L[ Chinese
Journal of Chemistry 0881^09"5#]499[
ðMo "m !O#"m!S# "m!OAc# "dtp# "py#Ł by the relatively
2
2
2
1
1
ð03Ł TEXSAN\ TEXRAY[ Structure Analysis Package\ Molecular
Structure Corporation\ The Woollands\ Texas\ 0876[
ð04Ł Wells AF[ Structural Inorganic Chemistry\ 3th ed[ Clarendon
press\ Oxford\ 0864\ p[ 315[
ð05Ł Shibahara T\ Hashimoto K\ Sakane G[ J[ Inorg[ Biochem[
0880^32]179[
small ligand in the reaction course are the two important
factors for the coupling of two cubane core
6¦
ðMo BiOS Ł [ For this novel structure\ the main features
2
2
are the ðMoÐOÐSŁ cavity and the ðMo "BiI # "m !O#"m !
2
2
2
2
1¦
S# "m!OAc# "py# Ł units[ In order to investigate the
2
1
2
ð06Ł Shibahara Y\ Akashi H\ Kuroya H[ J[ Am[ Chem[ Soc[
reactively and properties of this compound\ the improve!
ment of the synthesis is still under progress[
0
877^009]2202[
ð07Ł Yu R!M\ Lu S!F\ Huang X!Y\ Wu Q!J\ Huang J!Q\ submitted for
publication[
ð08Ł Kim J\ Rees GD[ Science 0881^146]0566[
Acknowledgements
ð19Ł Hegetschweiler K\ W oà rle M\ Meienkerger MD\ Nesper R\ Sch!
malle HW\ Hancock RD[ Inorg[ Chim[ Acta 0885^149]24[
ð10Ł Cheng W!D\ Zhang Q!E\ Huang J!S\ Lu J!X[ Polyhedron
0889^8"03#]0514[
ð11Ł Sun F!X[ MSc thesis\ Fujian Institute of Research on the Structure
of Matter\ Chinese Academy of Sciences\ 0886
ð12Ł Zheng Y\ Shang M!Y\ Zhang L!N\ Huang J!L\ Lu J!X[ Spect[
Anal[ 0872^1]61 "Chinese#[
This study was supported by the National Natural
Science Foundation of China\ the NSF of Fujian Prov!
ince and the state Key laboratory of Structural Chem!
istry[ We would like to thank Professor Yi!Xiong Fang
for his help in the preparation of this manuscript[
ð13Ł Huang J!L\ Huang J!Q\ Shang M!Y\ Lu J!X[ Adv[ Sci[ China
Chem[ 0889^2]044[
ð14Ł Lu S!F\ HuangJ!Q\ Huang X!Y\ Wu Q!J\ Yu R!M\ presented at
the 103th ACS National Meeting\ Las Vegas\ 0886[
ð15Ł Roh S!G\ Proust A\ Robert F\ Gouzerk P[ J[ Cluster Sci[
0885^6"3#]482[
ð16Ł Nyquist R[!A[ and Kagel R[ O[\ Infrared Spectra of Inorganic
Compounds\ New York\ London\ 0860\ p[ 360[
ð17Ł Cheng W!D\ Gao G!C\ Huang J!S\ Lu J!X[ Polyhedron
0884^03"12Ð13#]2538[
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