New dinuclear thiobenzoato complexes of molybdenum(V) containing Mo2O2S2 core. X-ray crystal structures of [Mo2O2S2(OSCC6H5) 2(py)2] and [Mo2O2S2(OSCC6H5) 2(γ-pic)2]·2H2O

Article abstract of DOI:10.1016/S0277-5387(98)00111-9

The [Mo₂O₂S₂(OSCC₆H₅) ₂] (1) has been prepared either by the reaction of [Mo₂O₃(C₅H₇O₂) ₄] or of [Mo₄Cl₂O₆(O₂CCH₃) ₆]·(CH₃CO)₂O with thiobenzoic acid. The product was then used to prepare two complexes of the general formula [Mo₂O₂S₂(OSCC₆H₅) ₂L₂] (where L = pyridine (2) or γ-picoline (3)). All complexes were characterized by elemental analyses, IR spectra and magnetic measurements. The structures of (2) and (3) were proved by X-ray structure analysis. Both complexes are dinuclear containing Mo₂O₂S₂ core with two Mo atoms linked by a Mo-Mo single bond. The Mo atoms are octahedrally coordinated by oxo-oxygen, two bridging sulfido-sulfurs, one pyridine (or γ-picoline)-nitrogen and thiobenzoato-sulfur and thiobenzoato-oxygen atoms.

Full text of DOI:10.1016/S0277-5387(98)00111-9

Polyhedron Vol[ 06\ No[ 08\ pp[ 2210Ð2214\ 0887
Þ 0887 Elsevier Science Ltd
Pergamon
All rights reserved[ Printed in Great Britain
9166Ð4276:87 ,08[99¦9[99
\
PII] S9166Ð4276"87#99000Ð8
New dinuclear thiobenzoato complexes of
molybdenum"V# containing Mo1O1S1 core[ X!ray
crystal structures of ðMo1O1S1"OSCC5H4#1"py#1Ł
and ðMo1O1S1"OSCC5H4#1"g!pic#1Ł=1H1O
Marina Cindric\ Visnja Vrdoljak\ Biserka Prugovecki and Boris Kamenarꢁ
ꢀ
³
³
Laboratory of General and Inorganic Chemistry\ Chemistry Department\ Faculty of Science\
University of Zagreb\ Ulica kralja Zvonimira 7\ POB 042\ 09990 Zagreb\ Croatia
"Received 06 December 0886^ accepted 8 March 0887#
Abstract*The ðMo1O1S1"OSCC5H4#1Ł "0# has been prepared either by the reaction of ðMo1O2"C4H6O1#3Ł or of
ðMo3Cl1O5"O1CCH2#5Ł="CH2CO#1O with thiobenzoic acid[ The product was then used to prepare two complexes
of the general formula ðMo1O1S1"OSCC5H4#1L1Ł "where L ꢂ pyridine "1# or g!picoline "2##[ All complexes were
characterized by elemental analyses\ IR spectra and magnetic measurements[ The structures of "1# and "2# were
proved by X!ray structure analysis[ Both complexes are dinuclear containing Mo1O1S1 core with two Mo atoms
linked by a MoÐMo single bond[ The Mo atoms are octahedrally coordinated by oxo!oxygen\ two bridging
sul_do!sulfurs\ one pyridine "or g!picoline#!nitrogen and thiobenzoato!sulfur and thiobenzoato!oxygen atoms[
Þ 0887 Elsevier Science Ltd[ All rights reserved
Keywords] crystal structure^ molybdenum"V# complexes^ thiobenzoato complexes^ dimeric structure[
———————————————————————————————————————————————
Relevance of molybdenum"V# complexes containing C5H4#1"py#1Ł "XꢂO or S# have been prepared by M[
MoÐS bonding to the molybdoenzymes is well known Rakowski DuBois in 0867 but their structures have
and extensively studied ð0Ð3Ł[ This is particularly true never been determined by X!ray di}raction method
due to the suggestion that the molybdoenzymes in the ð7Ł[ They were prepared using molybdenum"VI# com!
oxidized forms such as xanthine oxidase and sul_te pounds\ MoO1Cl1 and Na1MoO3[
oxidase contain oxo!molybdenum cores with the mol!
ybdenum atom coordinated by two or more sulfur
ligands[ The usual octahedral surroundings about
EXPERIMENTAL
molybdenum atoms in such systems are commonly
The starting acetylacetonato ðMo1O2"acac#3Ł ð8Ł and
completed by the additional nitrogen donor ligands
acetato ðMo3Cl1O5"O1CCH2#5Ł="CH2CO#1O ð09Ł com!
ð4Ł[ In addition\ interest in MoÐS chemistry has also
plexes were prepared as described earlier[ Reagent
grown due to the implication of this metal in the
grade solvents and all other chemicals were used with!
catalytic hydrodesulfurization processes ð5\ 6Ł[
out further puri_cation[
The IR spectra of KBr pellets were recorded on
In this paper we describe the synthesis and struc!
tural characterization of three new complexes con!
a FTIR 0599 Fourier!transform spectrometer in the
tainig MoS1Mo bridging core with thiobenzoato
3499Ð349 cm−0 region[ Magnetic measurements were
ligands as simultaneous oxygen and sulfur donors[
carried out at room temperature using Gouy method[
Two of them with additional pyridine and g!picoline
as nitrogen donor ligands[ Similar dinuclear di!m!oxo
and m!oxo!m!sul_do molybdenum"V# complexes of the
formulae ðMo1O2X"OSCC5H4#1Łn and ðMo1O2X"OSC
Preparation of ðMo1O1S1"OSCC5H4#1Ł "0#
Procedure "i#[ A mixture of ðMo1O2"acac#3Ł "0 g\
0[46 mmol# and thiobenzoic acid "0[7 g\ 02[92 mmol#
ꢁ Author to whom correspondence should be addressed[
in dichloromethane "09 cm2# was heated for 1 hours[
2210

2211
M[ Cindric et al[
The resulting red!brown precipitate was _ltered and up for 04 min[ After three days an orange!red crys!
washed with dichloromethane and methanol[ Yield] talline product was isolated[ Yield] 9[94 g\ 15)[
9[4 g\ 46)[
Procedure "ii#[ The same product was prepared by Calc[ for C13H19Mo1N1O3S3] C\ 39[9^ H\ 1[79^ Mo\
warming
mixture of ðMo3Cl1O5"O1CCH2#5Ł= 15[52^ N\ 2[78^ S\ 06[79)[ IR "cm−0#] 2954m\ 0484m\
Found] C\ 39[01^ H\ 1[64^ Mo\ 16[95^ N\ 2[25^ S\ 06[82[
a
"CH2CO#1O "9[14 g\ 9[14 mmol# with thiobenzoic acid 0359s\ 0335s\ 0324s\ 0298m\ 0137s\ 0119s\ 0901m\
"9[24 g\ 1[42 mmol# in dichloromethane "09 cm2# for 867s\ 839s\ 358m[
34 min[ After 1 days at room temperature red!brown
product was isolated[ Yield] 9[14 g\ 75)[ Found] C\
Preparation of ðMo1O1S1"OSCC5H4#1"g!pic#1Ł=1H1O
18[86^ H\ 0[47^ Mo\ 23[07^ S\ 11[05[ Calc[ for
"2#
C03H09Mo1O3S3] C\ 18[89^ H\ 0[68^ Mo\ 23[01^ S\
11[70)[ IR "cm−0#] 2950w\ 0481m\ 0344s\ 0310s\
0209m\ 0129s\ 0064s\ 863s\ 826s\ 728s\ 567s\ 364m[
Analogously as above\ to
a suspension of
ðMo1O1S1"OSCC5H4#1Ł "9[04 g\ 9[16 mmol# in dichlo!
romethane "09 cm2# g!picoline was added and the reac!
tion mixture warmed up for 04 min[ From the
resulting solution after three days an orange crys!
Preparation of ðMo1O1S1"OSCC5H4#1"py#1Ł "1#
Pyridine "0[4 cm2# was added to a suspension of talline product was isolated[ Yield] 9[94 g\ 14)[
ðMo1O1S1"OSCC5H4#1Ł "9[04 g\ 9[16 mmol# in dichlo! Found] C\ 28[18^ H\ 2[68^ Mo\ 13[56^ N\ 2[80^ S\ 05[90[
romethane "04 cm2# and the reaction mixture warmed Calc[ for C15H17Mo1N1O5S3] C\ 28[79^ H\ 2[59^ Mo\
Table 0[ Crystal data for ðMo1O1S1"OSCC5H4#1"py#1Ł "1# and ðMo1O1S1"OSCC5H4#1
"g!pic#1Ł=1H1O "2#
1
2
Formula
C13H19Mo1N1O3S3
C15H17Mo1N1O5S3
Mol[ wt
619[43
9[14×9[19×9[24
red
03[342"2#
09[145"1#
07[436"2#
89
86[21"2#
89
1615[7"8#
monoclinic
3
673[51
9[19×9[09×9[44
Crystal size "mm#
Colour
orange!red
02[806"1#
8[711"0#
13[670"5#
89
091[25"1#
89
2297[8"09#
monoclinic
3
Ä
a "A#
Ä
b "A#
Ä
c "A#
a ">#
b ">#
g ">#
2
Ä
V "A #
Crystal system
Z
dcalc[ "gcm−2
#
0[644
0[464
Space group
Temp[ ">C#
Scan method
1U range ">#
hkl range
C1:c
12
UÐ1U
3Ð59
219\¦03\¦15
0[4
P10:c
12
v
3Ð59
208\¦02\¦23
1
Max time:r~n"h#
m"MoÐKa#
01[48
09[38
"cm−0
#
Data measured
3219
8854
Unique data
2882
8284
Observed data ðI×1s"I#Ł
Number of variables
0599
052
9[552:−9[791
9[951
9[037
1464
250
0[226:−0[163
9[983
9[132
2
2
Ä
Max:min Dr "e :A #
R0a for r~n[ with I×1s"I#
1
wR1b"Fo #
GooFc
9[807
9[805
a R0ꢀS==Fc=−=Fc==:S=Fo=[
1
b wR1ꢂðSw"Fo!Fc#1:S wFo1Ł0:1\ wꢂ0:ðs1"Fo #¦"aP#1¦bPŁ\ aꢂ9[9476 for 1\ aꢂ9[9823
for 2\ bꢂ9[99 for 1 and 2\ Pꢂ"max"Fo1 or 9#¦1 Fc1#:2[
1
c GooFꢂSꢂðSw"Fo !Fc1#1:"n!p#Ł0:1
[

New dinuclear thiobenzoato complexes of molybdenum"V#
2212
13[34^ N\ 2[46^ S\ 05[23)[ IR "cm−0#] 2956m\ 0507s\ them[ They cracked very easily[ This is most probably
0484m\ 0351s\ 0324s\ 0296m\ 0124s\0914m\ 867s\ 833s\ the reason for relatively high reliability index for the
354m[
structure of 2[ The distances and angles were cal!
culated by SHELXL85 and PARST ð02Ł program\ the
molecular and crystal structures by ORTEP!2 ð03Ł[
All calculations were performed on an IBM PC:AT
compatible microcomputer "processor 79375:
55 MHz#[
Tables with complete interatomic distances and
angles\ positional and anisotropic thermal
parameters\ and observed and calculated structure
factors for the two structures have been deposited
with the Editor\ from whom copies are available on
request[
X!ray crystallo`raphy
Intensity data were collected at 182 K by using
graphite!monochromated Mo!Ka radiation "lꢂ
9[6096 A# on a STOE updated Philips PW0099
di}ractometer[ Three standard re~ections were moni!
tored periodically[ Intensity variations of 7[8) "1#
and 8[8) "2# were observed and consequently cor!
rected for in the data reduction[ The intensities were
reduced to Fo by applying corrections for Lorentz and
polarization e}ects[ Absorption corrections were not
applied[
Ä
RESULTS AND DISCUSSION
The structures of both compounds were solved by
using direct methods implemented in SIR81 programs
The complex 0 was prepared by two alternative
ð00Ł and succesive Fourier syntheses[ The re_nements ways\ either by the reaction of ðMo1O2"C4H6O1#3Ł or
were performed by full matrix least squares method of ðMo3Cl1O5"O1CCH2#5Ł="CH2CO#1O with thio!
assuming anisotropic temperature factors for all non! benzoic acid[ The product was stable and insoluble in
H atoms using SHELXL85 ð01Ł program[ All hydro! all common solvents suggesting its polynuclear nature
gen atoms\ except those belonging to the water mol! ðMo1O1S1"OSCC5H4#1Łn rather with six than _ve!coor!
ecules\ were calculated on the geometrical ground and dinated molybdenum atom[ The complex containing
treated with the constrained lengths in the re_nement[ _ve!coordinated molybdenum would be unsaturated
Hydrogen atoms of water molecules were not located[ and therefore more reactive[ Its IR spectrum supports
Crystal parameters\ data collection details for both such structure] strong broad band at 728 cm−0 is
compounds and the results of the re_nements are sum! indicative for an intermolecular metal[[[ oxygen inter!
marized in Table 0[ Selected bond lengths and angles action "MoꢂO===MoꢂO===# the same as it has been
are listed in Table 1[ Crystals of 2 were extremely observed for ðMo1O3"OSCC5H4#1Łn at 729 cm−0 ð7Ł[
fragile thus causing di.culties to manipulate with Due to its insolubility we were not able to prepare
Ä
Table 1[ Selected bond lengths "A# and angles "># for ðMo1O1S1"OSCC5H4#1"py#1Ł "1# and ðMo1O1S1"OSCC5H4#1"g!
pic#1Ł=1H1O "2#
1
2
Mo0ÐO0
Mo0ÐO1
Mo0ÐN0
Mo0ÐS0
Mo0ÐS0?
Mo0ÐS1
Mo0ÐMo0?
O0ÐMo0ÐN0
O1ÐMo0ÐN0
O0ÐMo0ÐS0
O1ÐMo0ÐS0
N0ÐMo0ÐS0
O0ÐMo0ÐS0?
O1ÐMo0ÐS0?
S0ÐMo0ÐS0?
O0ÐMo0ÐS1
O1ÐMo0ÐS1
N0ÐMo0ÐS1
S0ÐMo0ÐS1
S0?ÐMo0ÐS1
0[574"4#
1[146"3#
1[294"4#
1[209"1#
1[211"1#
1[479"1#
1[711"0#
75[8"1#
Mo00ÐO00
Mo00ÐO01
Mo00ÐN00
Mo00ÐS00
Mo00ÐS01
Mo00ÐS01
Mo00ÐMo10
O00ÐMo00ÐN00
O01ÐMo00ÐN00
O00ÐMo00ÐS00
O01ÐMo00ÐS00
N00ÐMo00ÐS00
O00ÐMo00ÐS10
O01ÐMo00 ÐS10
S10ÐMo00ÐS00
O00ÐMo00ÐS01
O01ÐMo00ÐS01
N00ÐMo00ÐS01
S00ÐMo00ÐS01
S10ÐMo00ÐS01
0[568"7#
1[152"7#
1[168"7#
1[205"2#
1[203"2#
1[456"2#
1[720"0#
76[1"2#
63[3"2#
097[5"2#
78[6"1#
74[0"1#
093[3"2#
89[3"1#
090[85"00#
84[2"2#
51[8"1#
70[9"1#
040[61"00#
75[99"00#
Mo10ÐO10
Mo10ÐO11
Mo10ÐN10
Mo10ÐS00
Mo10ÐS10
Mo10ÐS11
0[573"7#
1[169"6#
1[161"7#
1[210"2#
1[207"2#
1[468"2#
O10ÐMo10ÐN10
O11ÐMo10ÐN10
O10ÐMo10ÐS10
O11ÐMo10ÐS10
N10ÐMo10ÐS10
O10ÐMo10ÐS00
O11ÐMo10 ÐS00
S10ÐMo10ÐS00
O10ÐMo10ÐS11
O11ÐMo10ÐS11
N10ÐMo10ÐS11
S10ÐMo10ÐS11
S00ÐMo10ÐS11
77[1"2#
64[6"2#
096[3"2#
80[7"1#
73[3"1#
093[1"2#
77[7"1#
090[57"09#
84[0"2#
51[4"1#
70[8"1#
65[0"1#
096[7"1#
77[26"01#
73[2"1 #
092[3"1#
89[52"00#
091[20"6#
86[3"1#
51[89"00#
70[65"03#
049[22"6#
75[19"6#
042[03"01#
75[14"09#
Mo0ÐS0ÐMo0? 64[97"5#
Mo00ÐS00ÐMo10 64[14"8#
Mo00ÐS10ÐMo10 64[23"09#

2213
M[ Cindric et al[
suitable crystals to prove this structure also by the X! 0[ However\ while the molecular structure of the 1 has
ray di}raction method[ The formation of the crystallographically imposed two!fold symmetry axis
MoS1Mo bridge may be explained by the apperance of the structure 2 exhibits a pseudo two!fold symmetry[
H1S produced in situ from the molybdenum catalyzed The octahedral coordination about each molybdenum
hydrolysis of thiobenzoic acid[ The analogous obser! atom within a dimer is considerably distorted with the
vations have been made also in preparing some other angles ranging from 65[0"1# to 096[7"1#> in 1 and from
molybdenum"V# complexes with thio!ligands ð04Ð07Ł[ 63[3"2# to 097[5"2#> in 2[ The distances between two
Ä
The strong donor ligands such as pyridine or g!pico! Mo atoms of 1[711"0# in 1\ and 1[720"0# A in 2 are
line stabilized the dinuclear structures producing com! indicative of a single MoÐMo bond ð08\ 19Ł[ The
plexes 1 and 2[
observed diamagnetism of these complexes suggests a
The structures of ðMo1O1S1"OSCC5H4#1"py#1Ł "1# strong metal!metal interactions[ In both compounds
and ðMo1O1S1"OSCC5H4#1"g!pic#1Ł=1H1O "2# are built the two molybdenum atoms are bridged via two sulfur
up of dinuclear complex molecules as shown in Fig[ atoms with average values for the MoÐSbr bond lengths
Fig[ 0[ ORTEP!2 illustration of the structures of "a# ðMo1O1S1"OSCC5H4#1"py#1Ł "1# and "b# ðMo1O1S1"OSCC5H4#1
"g!pic#1Ł=1H1O "2# showing the atom numbering schemes and thermal ellipsoids "49)# for the atoms[ The H atoms are
unlabelled[

New dinuclear thiobenzoato complexes of molybdenum"V#
2214
Ä
Ä
3[ Stiefel\ E[ I[\ in Molybdenum and Molybdenum!
Containin` Enzymes\ ed[ M[ P[ Coughlan\
Pergamon Press\ New York\ 0879\ p[ 30[
4[ Hahn\ R[\ Kusthardt\ U[ and Scherer\ W[\ Inor`[
Chim[ Acta[\ 0882\ 109\ 066[
5[ Massoth\ F[ E[\ Adv[ Catal[\ 0867\ 76\ 154[
6[ Enemark\ J[ H[\ in Nitro`en Fixation\ The Chemi!
of 1[205"1# A in 1 and of 1[204"2# A in 2\ respectively
ð06\ 10Ł[ The four!membered rings of the Mo1S1
bridging core are not planar but folded along the lines
connecting two bridging sulfur atoms] the dihedral
angles between two SMoS planes are 047[24"9# and
046[1"1#> in 1 and 2\ respectively[ The Mo1O bond
Ä
lengths of 0[574"4#\ and 0[568"7# and 0[573"7# A for 1
and 2\ respectively are normal values for such bond
cal!Biochemical!Genetic Interface\ ed[ A[ Muller
Ã
and W[ E[ Newton\ Plenum Press\ New York\
to the terminal oxo!oxygen atoms ð11Ł[ The MoÐS
bond lengths ð1[479"1# in "1#\ 1[456"2# and 1[468"2# A
0872\ p[ 218[
Ä
7[ Rakowski DuBois\ M[\ Inor`[ Chem[\ 0867\ 06\
1394[
in 2Ł as well as the MoÐO bond lengths ð1[146"3# in 1\
8[ Moore\ F[ W[ and Rice\ R[ E[\ Inor`[ Chem[\ 0857\
6\ 1409[
09[ Kamenar\ B[\ Korpar!Colig\ B[ and Penavic\ M[\
ꢀ
J[ Chem[ Soc[\ Dalton Trans[\ 0870\ 200[
00[ Altomare\ A[\ Burla\ M[ C[\ Camalli\ M[\
Cascarano\ G[\ Giacovazzo\ C[\ Guagliardi\ A[
and Polidori\ G[\ SIR81\ 0883[
Ä
1[152"7# and 1[169"6# A in 2Ł from the thiobenzoato
ligands are in good agreement with the values found
for such bonds in similar molybdenum"V# structures
ð12Ð14Ł[ The molybdenum!to!thiobenzoato!oxygen
bond lengths are lengthened due to the trans in~uence
of the terminal oxo!oxygen atoms[ The same applies
³
to the molybdenum!to!thiobenzoato sulfur and mol! 01[ Sheldrick\ G[ M[\ SHELXL85\ Pro`ram for the
Solution of Crystal Structure[ University of Got!
tingen\ Germany "0885#[
02[ Nardelli\ M[\ Comput[ Chem[\ 0872\ 6\ 0884[
03[ Farrugia\ L[ J[\ ORTEP!2\ Version 0[91b[ Uni!
versity of Glasgow\ U[K[\ 0886[
ybdenum!to!nitrogen bonds ð1[294"4# in 1\ 1[168"8#
and 1[161"7# A in 2Ł owing to their trans positions to
the bridging sul_do!sulfur atoms ð15\ 16Ł[ Bond leng!
ths and angles within thiobenzoato ligands\ pyridine
and g!picoline are within expected values[
Ä
04[ Ott\ V[ R[\ Swieter\ D[ S[ and Schultz\ F[ A[\
Two water molecules in 2 are hydrogen!bonded to
each other having O0w[[[O1w distance amounting to
Inor`[ Chem[\ 0866\ 05\ 1427[
³
05[ Kamenar\ B[\ Korpar!Colig\ B[\ Cindric\ M[\
ꢀ
Ä
1[65"0# A[ Otherwise there are no any other than van
Penavic\ M[ and Strukan\ N[\ J[ Chem[ Soc[\
ꢀ
der Waals interactions between the complex and water
molecules[
Dalton Trans[\ 0881\ 1982[
06[ Bhattacharyya\ R[\ Chakrabarty\ P[ K[\ Ghosh\ P[
N[\ Mukherjee\ A[ K[\ Podder\ D[ and Mukherjee\
M[\ Inor`[ Chem[\ 0880\ 29\ 2837[
07[ Howlader\ N[ C[\ Haight\ G[ P[ Jr[\ Hambley\ T[
W[\ Snow\ M[ R[ and Lawrance\ G[ A[\ Inor`[
Chem[\ 0873\ 12\ 0700[
The IR spectra of all three complexes con_rm the
presence of CÐS group at 826 "complex 0#\ 839 "1# and
833 cm−0"2#\ as well as of the CÐO group at 0334
"complex 0#\ 0359 "1# and 0351 cm−0 "2#\ respectively[
The strong apsorption maxima at 863 and 364 "com!
plex 0#\ 867 and 358 "1#\ 867 and 354 cm−0 "2#\ belong
to the MoÐO "terminal# and MoÐS "bridging# stret!
ching frequencies\ respectively ð7\ 06\ 17Ł[
08[ Dulebohn\ J[ I[\ Stomatakos\ T[ C[\ Ward\ D[ L[
and Nocera\ D[ C[\ Polyhedron\ 0880\ 09\ 1702[
19[ Mizutani\ J[ and Imoto\ H[\ Saito\ T[\ Acta Crys!
tallo`r[\ Sect[ C\ 0886\ 42\ 36[
10[ Schroder\ F[ A[\ Z[ Naturforsch[\ 0864\ 29b\ 527[
Ã
11[ SchroÃder\ F[ A[\ Acta Cryst[\ 0864\ B20\ 1183[
Acknowled`ements*This research was supported by the
Ministry of Science and Technology of the Republic of
Croatia "Grant No[ 008396#[
³
12[ Kamenar\ B[\ Korpar!Colig\ B[\ Penavic\ M[ and
ꢀ
Cindric\ M[\ J[ Cryst[ Spectr[ Res[\ 0881\ 11\ 280[
ꢀ
13[ Alyea\ E[ C[\ Ferguson\ G[\ Parvez\ M[ and Som!
ogyvari\ A[\ Polyhedron\ 0874\ 3\ 672[
14[ Coucouvanis\ D[\ Hadjikyriacou\ A[\ Toupa!
dakis\ A[\ Koo\ S[!M[\ Ileperuma\ O[\ Draganjac\
M[ and Salifoglou\ A[\ Inor`[ Chem[\ 0880\ 29\
643[
15[ Kamenar\ B[\ Kaitner\ B[ and Strukan\ N[\ Croat[
Chem[ Acta[\ 0880\ 53\ 218[
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