Synthesis, characterization and X-ray crystal structure of [Ag(Htsa)(PPh3)3] (H2tsa=o-HS(C6H4)CO2H). Comparison with [Au(Htsa)(PPh3)]

Article abstract of DOI:10.1016/S0277-5387(98)00141-7

A novel, monomeric triphenylphosphine silver(I) complex [Ag(Htsa)(PPh₃)₃] (H₂tsa=o-HS(C₆H₄)CO₂H) was synthesized from three different ligand-exchange reactions, as 3 without any solvate or as 3a with CH₂Cl₂ solvate, in good yield. The complex 3 can be interconverted with the previously obtained, two antimicrobially-active silver(I) thiosalicylates; one was the oligomeric, water-soluble complex {Na[Ag(tsa)] · H₂O}_n, 1 (n=21-27) and the other the polymeric, water-insoluble complex [Ag(Htsa)]_n, 2. The analogous gold(I) complex [Au(Htsa)(PPh₃)], 4, was also isolated. The complexes 3, 3a and 4 were characterized with complete elemental analyses, TGDTA, FT-IR and multinuclear NMR (¹H, ¹³C, ³¹P and ¹⁰;Ag) spectroscopies. The crystal structures of 3 and 4 were determined with single-crystal X-ray diffraction. The monomeric structure for 3 and the dimeric structure via hydrogen bonds of the carboxylic acid for 4 in the solid state were found.

Full text of DOI:10.1016/S0277-5387(98)00141-7

Polyhedron Vol[ 06\ No[ 19\ pp[ 2408Ð2429\ 0887
Þ 0887 Elsevier Science Ltd
Pergamon
All rights reserved[ Printed in Great Britain
9166Ð4276:87 ,08[99¦9[99
\
PII] S9166Ð4276"87#99030Ð6
Synthesis\ characterization and X!ray crystal
structure of ðAg"Htsa#"PPh2#2Ł
"H1tsaꢀo!HS"C5H3#CO1H#[
Comparison with ðAu"Htsa#"PPh2#Ł
Kenji Nomiya\ꢀ\ Noriko Chikaraishi Kasuga\ Izumi Takamori
and Kazuhiro Tsuda
Department of Materials Science\ Faculty of Science\ Kanagawa University\ Hiratsuka\
Kanagawa 148!0182\ Japan
"Received 1 February 0887^ accepted 5 April 0887#
Abstract*A novel\ monomeric triphenylphosphine silver"I# complex ðAg"Htsa#"PPh2#2Ł "H1tsaꢁo!HS"C5H!
3#CO1H# was synthesized from three di}erent ligand!exchange reactions\ as 2 without any solvate or as 2a with
CH1Cl1 solvate\ in good yield[ The complex 2 can be interconverted with the previously obtained\ two
antimicrobially!active silver"I# thiosalicylates^ one was the oligomeric\ water!soluble complex "NaðAg"ts!
a#Ł = H1O#n\ 0 "nꢁ10Ð16# and the other the polymeric\ water!insoluble complex ðAg"Htsa#Łn\ 1[ The analogous
gold"I# complex ðAu"Htsa#"PPh2#Ł\ 3\ was also isolated[ The complexes 2\ 2a and 3 were characterized with
complete elemental analyses\ TG:DTA\ FT!IR and multinuclear NMR "0H\ 02C\ 20P and 098Ag# spectroscopies[
The crystal structures of 2 and 3 were determined with single!crystal X!ray di}raction[ The monomeric structure
for 2 and the dimeric structure via hydrogen bonds of the carboxylic acid for 3 in the solid state were found[
Þ 0887 Elsevier Science Ltd[ All rights reserved
Keywords] thiosalicylate^ triphenylphosphine^ silver"I# complex^ gold"I# complex^ X!ray crystal structure^ NMR[
———————————————————————————————————————————————
0[ INTRODUCTION
thio!D!glucopyranosato!S#"triethylphosphine#gold"I##
ð5Ð09\ 03Ð05Ł\ which has been used in chemotherapy
as an e}ective antiarthritic agent and also as a realized
medicine of oral!administration\ although its mech!
anism or mode of action is unclari_ed as yet ð5Ð09Ł[ On
the other hand\ for non!crystalline\ polymeric metalÐ
thiolate and metalÐimidazolate compounds\ only a
few structural studies have been performed by
synchrotron X!ray studies containing EXAFS\
XANES\ WAXS and DAS ð00\ 01Ł and by Rietveld
In the medicinally or pharmaceutically active com!
pounds of silver"I# and gold"I#\ most of the complexes
formed with thiol and nitrogen!containing het!
erocyclic ligands are harder to crystallize and are
believed to be polymeric ð0Ð32Ł[ In general\ tertiary
phosphine ligands have been usually employed in
order to obtain crystalline compounds ð12Ð24\ 30\ 31Ł\
although several crystalline thiolatogold"I# complexes
without tertiary phosphines such as ðAu"SR#1Łn− analysis using powder X!ray di}raction data ð33\ 34Ł[
"HSRꢁmercapto!group compound# have been
recently found ð06Ð11\ 28Ł[ Probably\ a recent devel!
opment of monomeric AuI compounds composed of
both thiol and tertiary phosphine ligands stems from
a discovery of aurano_n ""1\2\3\5!tetra!O!acetyl!b!0!
Very recently\ we have prepared a monomeric imid!
azolatotris"triphenylphosphine# silver"I# complex
ðAg"imd#"PPh2#2Ł "Himdꢁimidazole# ð30Ł by a reac!
tion of PPh2 ligands in CH1Cl1 with a polymeric com!
plex ðAg"imd#Łn which has shown wide spectra of
excellent antibacterial and antifungal activities ð31Ł[
This monomeric complex was neither obtained from
reactions
of
precursors
ðAgCl"PPh2#2Ł
and
ꢀAuthor to whom correspondence should be addressed[
Tel[] ¦70!352!483000^ Fax] ¦70!352!478573^ E!mail]
nomiyaÝinfo[kanagawa!u[ac[jp
ðAgCl"PPh2#1Ł1 with a free Himd ligand in the presence
of NaOH nor of ðAgCl"PPh2#1Ł1 with sodium salt of
2408

2419
K[ Nomiya et al[
imidazolate[ On the contrary\ the corresponding AuI respectively[ Polymeric\ water!insoluble and orange
complex ðAu"imd#"PPh2#Ł was obtained from a reac! complex ðAg"Htsa#Łn\ 1\ was prepared as previously
tion of the precursor ðAuCl"PPh2#Ł with the Himd described ð27Ł[
ligand in the presence of NaOH[
Also\ two types of thiosalicylatosilver"I# complexes
have been recently found ð27Ł^ one was an oligomeric\ 1[1[ Instrumentation:analytical procedures
water!soluble and yellow complex "NaðAg"ts!
a#Ł = H1O#n\ 0 "nꢁ10Ð16^ H1tsaꢁo!HS"C5H3#CO1H#
Elemental analyses on samples dried overnight at
and the other a polymeric\ water!insoluble and orange room temperature under 09−2Ð09−3 Torr were carried
complex ðAg"Htsa#Łn\ 1\ both of which have displayed out by Mikroanalytisches Labor Pascher "Remagen\
e}ective antimicrobial activities against selected bac! Germany#[ Infrared spectra were obtained on a
teria\ yeast and molds[ The present work has been JASCO FT!IR 299 spectrometer as KBr disks at room
aimed at "i# preparing a monomeric form of the thio! temperature[ Thermogravimetric "TG# and di}er!
salicylatosilver"I# complex\ e[g[ ðAg"Htsa#"PPh2#2Ł\ 2\ ential thermal analyses "DTA# were acquired using
through ligand!exchange reactions of polymeric com! a Rigaku TG 7090D and TAS 299 data!processing
plex 1 or of some precursor silver"I# complexes such system[ TG:DTA measurements were run under air
as ðAgCl"PPh2#2Ł and ðAgCl"PPh2#1Ł1\ "ii# applying the with a temperature ramp of 0>C:min between 19 and
same concept to gold"I# chemistry to obtain the thios! 499>C[
alicylatogold"I# complex\ e[g[ ðAu"Htsa#"PPh2#Ł\ 3\ "iii#
0H NMR "288[54 MHz#\ 02C NMR "099[3 MHz#
providing X!ray crystal structures of 2 and 3 in the and 20P NMR "050[69 MHz# spectra were recorded at
solid state and "iv# clarifying the behavior in solution 11>C in 4 mm o[d[ tubes on a JEOL JNM!EX 399 FT!
of 2 and 3[ The X!ray crystal structures of several NMR spectrometer with a JEOL EX!399 NMR data!
"arenethiolato#metal complexes have been deter! processing system[ H and 02C"0H# NMR spectra of
0
mined such as ðAu"Htsa#"PCy2#Ł "PCy2ꢁtricyclo! the complexes were measured in CDCl2 with reference
hexylphosphine# ð15Ł\ ðCu"SC5H3NMe1!1#Ł2\ ðCu"S!0! to an internal standard of tetramethylsilane "TMS#[
C09H5NMe1!7#Ł8\ ðCu2"S!0!C09H5NMe1!7#1"C2CtBu#Ł1 Chemical shifts are reported on the d scale and res!
ð35Ł\
ðCu7"SC5H2"CH1NMe1#1!1\5#2Br4Ł
ð36Ł\ onances down_eld of TMS "d 9# are recorded as posi!
ðMg"S"C5H3!1!CH1NMe1##1Ł1 ð37Ł and ðLi"SC5H3""R#! tive[ 20P"0H# NMR spectra of the complexes were
CH"Me#NMe1#!1#Ł5 and ðLi"SC5H2"CH1NMe1#1!1\5#Ł5 measured in CDCl2 with reference to an external stan!
ð38Ł[
dard of 14) H2PO3 in H1O in a sealed capillary[
Herein we report the full details of the synthesis and Chemical shifts are reported as negative for res!
characterization of the complexes ðAg"Htsa#"PPh2#2Ł\ onances up_eld of H2PO3 "d 9#[ The 20P"0H# NMR
2\ in 26) yield and ðAg"Htsa#"PPh2#2Ł = CH1Cl1\ 2a\ spectra at −89>C were measured in CD1Cl1 with an
in 41) yield both as colorless needle crystals\ and external standard of 14) H2PO3 by a substitution
ðAu"Htsa#"PPh2#Ł\ 3\ in 61) yield as pale yellow prism method[
crystals[ The X!ray crystal structures of 2 and 3 were
The two!dimensional 0HÐ02C COSY NMR spectra
0
determined by single!crystal X!ray di}raction[ Also and both two!dimensional NMR spectra of HÐ02C
reported are the compositional characterization of 2\ HMBC "heteronuclear multiple bond correlation#
2
0
2a and 3 by full elemental analyses\ FT!IR\ ther! method by a correlation JCÐH between H and 02C
moglavimetric and di}erential thermal analyses atoms separated by three bonds and HÐ02C HMQC
0
"TG:DTA# and their structural characterization in "heteronuclear multiple quantum coherence# by a cor!
0
solution by 0H\ 02C and 20P NMR spectroscopies\ and relation between H and 02C which are directly spinÐ
additionally by solution 098Ag NMR spectroscopy for spin coupled\ were measured in CDCl2 solution\ all
2[
spectra referenced to an internal TMS in 4 mm o[d[
tubes using a JEOL JNM!EX 399 NMR spectrometer
and JEOL EX!399 NMR data!processing system or
using a VARIAN UNITY 499 FT!NMR spec!
trometer[ Pulse sequences and spectral parameters for
the HMBC and HMQC methods are reported else!
where ð44Ł[
1[ EXPERIMENTAL
1[0[ Materials
098Ag NMR "07[34 MHz# spectra were recorded at
11>C in 09 mm o[d[ tubes on a JEOL JNM!EX 399
All chemicals were reagent grade and were used as FT!NMR spectrometer equipped with a JEOL NM!
received] thiosalicylic acid "H1tsa^ o!mercaptobenzoic 39T09L low!frequency tunable probe[ The 098Ag
acid#\ AgNO2\ NaðAuCl3Ł = 1H1O\ "C5H4#2P\ NaOH\ NMR spectra of the complexes were measured in
ethanol\ acetone\ diethyl ether\ dichloromethane "all CDCl2 with reference to an external standard of satu!
from Wako#^ CDCl2\ DMSO!d5 "Aldrich#^ CD1Cl1 rated AgNO2ÐD1O solution by a substitution method[
"Isotec#[ Several precursor complexes such as ðAgCl Chemical shifts are reported on the d scale with res!
"PPh2#2Ł ð49Ł\ ðAgCl"PPh2#1Ł1 ð40Ł and ðAuCl"PPh2#Ł onances down_eld of AgNO2 "d 9# as positive[ Spectral
ð41Ð43Ł were prepared according to the literature\ parameters for 098Ag NMR include] pulse width of

Synthesis\ characterization and X!ray crystal structure of ðAg"Htsa#"PPh2#2Ł "H1tsaꢁo!HS"C5H3#CO1H# 2410
02[1 ms\ acquisition time of 9[28 s\ recycle time of 0[28 s gradually started around 049>C[ IR "KBr disk#] n
and sweep width of 10\997 Hz[
0692vs\ 0472m\ 0368s\ 0322vs\ 0216m\ 0298m\ 0162m\
0110w\ 0071w\ 0046w\ 0981s\ 0915m\ 888m\ 631vs\
0
583vs\ 402vs cm−0[ H and 02C NMR in CDCl2 are
1[2[ Preparation of the complexes
ðAg"Htsa#"PPh2#2Ł\ 2] From
shown in Table 2[ 20P NMR "CDCl2#] d 3[44 "PPh2#[
098Ag NMR "CDCl2#] d 0085[
a
reaction of
2a] From a reaction of polymer ðAg"Htsa#Łn with
ðAgCl"PPh2#1Ł1 with H1tsa in the presence of NaOH[ PPh2[ To a yellow suspension of 9[411 g "1[99 mmol# of
To 9[599 g "9[338 mmol# ðAgCl"PPh2#1Ł1 dissolved in powder!solid ðAg"Htsa#Łn in 39 ml ethanol was added a
39 ml dichloromethane was added a clear yellow solu! clear colorless solution of 0[46 g "5[99 mmol# of tri!
tion of 9[039 g "9[897 mmol# of H1tsa and 9[925 g phenylphosphine in 019 ml dichloromethane[ Stirring
"9[899 mmol# of NaOH in 49 ml ethanol[ The yellowÐ continued for 2 h[ During the initial 04 min!stirring\
white suspension obtained was stirred for 29 min and the solution became clear yellow[ The clear _ltrate
_ltered through a folded _lter paper "Whatman No[ obtained by passing through a folded _lter paper
4#[ The clear _ltrate was concentrated at 59>C to a "Whatman No[ 1# was slowly evaporated at room
volume of ca[ 69 ml by rotary evaporation\ followed temperature[ A crude compound of pale yellow plate
by standing for a few days in a refrigerator at 4>C[ crystals formed within a few days was collected on a
Colorless needle crystals formed were collected on membrane _lter "JG 9[1 mm#\ washed with ethanol
a membrane _lter "JG 9[1 mm#\ washed with water "099 ml×1# and then with diethyl ether "099 ml×1#
"099 ml×1#\ then with ethanol "099 ml×1# and _nally and dried in vacuo for 1 h[ The yield of this crude
with 099 ml diethyl ether\ and dried in vacuo for 1 h[ product was 0[53 g[
Yield] 9[24 g "26[3)# of light! and thermally!stable\
To the crude product redissolved in 39 ml dichlo!
colorless needle crystals\ which were soluble in chloro! romethane was added 39 ml ethanol\ followed by _l!
form and dichloromethane\ sparingly soluble in tering through a _lter paper "Whatman No[ 1# and
DMSO\ acetone and acetonitrile\ but insoluble in the _ltrate was slowly evaporated by standing for a
water\ ethanol and diethyl ether[
few days at room temperature[ Colorless needle crys!
Found] H\ 3[70^ C\ 69[99[ Calc[ for H49C50O1P2SAg tals formed here were collected on a membrane _lter
or ðAg"Htsa#"PPh2#2Ł] H\ 3[70^ C\ 58[81[ TG:DTA] "JG 9[1 mm#\ washed twice each with 099 ml ethanol
no weight loss observed below 049>C^ decomposition and 099 ml diethyl ether and dried in vacuo for 1 h[
started around 049>C with an endothermic peak at Yield] 9[84 g "31[0)#[
069>C[ IR "KBr disk#] n 0690vs\ 0472m\ 0368s\ 0322vs\
Found] H\ 3[48^ C\ 54[83[ Calc[ for H41C51O1P!
0216m\ 0298m\ 0160m\ 0106m\ 0073w\ 0046m\ 0982m\ 2SCl1Ag or ðAg"Htsa#"PPh2#2Ł = CH1Cl1] H\ 3[52^ C\
0
0915m\ 886m\ 631vs\ 583vs\ 404s\ cm−0[ H and 02C 54[63[ TG:DTA] weight loss of 6[13) observed below
NMR in CDCl2 are shown in Table 2[
ðAg"Htsa#"PPh2#2Ł = CH1Cl1\ 2a] From a reaction of ðAg"Htsa#"PPh2#2Ł = xCH1Cl1\
014>C with an endothermic peak at 093>C^ Calc[ for
6[49) "xꢁ0#^
ðAgCl"PPh2#2Ł with H1tsa in the presence of NaOH[ decomposition started around 049>C with an endo!
To 1[68 g "2[99 mmol# ðAgCl"PPh2#2Ł dissolved in 59 ml thermic peak at 069>C[ IR "KBr disk#] n 0693vs\
dichloromethane was added a clear yellow solution of 0473m\ 0367s\ 0322vs\ 0216w\ 0297w\ 0161m\ 0111w\
9[352 g "2[99 mmol# of H1tsa and 9[019 g "2[99 mmol# 0071w\ 0046m\ 0981s\ 0916m\ 887m\ 631vs\ 583vs\
0
of NaOH in 079 ml ethanol[ The yellowÐwhite sus! 401vs\ cm−0[ H and 02C NMR in CDCl2 are shown
pension obtained was stirred for 29 min and _ltered in Table 2[ 20P NMR "CDCl2#] d 3[46 "PPh2#[
through a folded _lter paper "Whatman No[ 4#[ The
ðAu"Htsa#"PPh2#Ł\ 3] This compound was prepared
clear _ltrate was concentrated at 59>C to a volume of by a modi_cation of the literature method ð15Ł\ using
ca[ 199 ml by rotary evaporation\ followed by stand! 9[136 g "9[499 mmol# of ðAuCl"PPh2#Ł\ 9[966 g
ing for a few days in a refrigerator at 4>C[ Colorless "9[499 mmol# of H1tsa in 49 ml ethanol and 0 ml
needle crystals formed were collected on a membrane "9[499 mmol# of 9[4 M NaOH aqueous solution[
_lter "JG 9[1 mm#\ washed with water "099 ml×1#\ then Yield] 9[11 g "61[9)# of pale yellow cubic crystals
with ethanol "099 ml×1# and _nally with 099 ml with melting point 043Ð045>C\ which were soluble in
diethyl ether and dried in vacuo for 1 h[ Yield] 0[64 g acetone\ chloroform and benzene\ sparingly soluble in
"40[4)# of colorless needle crystals\ which were sol! ethanol\ but insoluble in water and diethyl ether[ This
uble in chloroform and dichloromethane\ sparingly compound was light! and thermally!stable[
soluble in DMSO\ acetone and acetonitrile\ but insol!
uble in water\ ethanol and diethyl ether[
Found] H\ 2[20^ C\ 37[81^ O\ 4[36^ P\ 4[08^ S\ 4[98^
Au\ 20[39^ total 88[27)[ Calc[ for H19C14O1PSAu or
Found] H\ 3[63^ C\ 54[80^ O\ 1[55^ P\ 7[09^ S\ 1[52^ ðAu"Htsa#"PPh2#Ł] H\ 2[18^ C\ 38[92^ O\ 4[11^ P\ 4[95^
Cl\ 4[64^ Ag\ 8[57^ total 88[36)[ Calc[ for H41C51O1P! S\ 4[12^ Au\ 21[05[ TG:DTA] negligible weight loss
2SCl1Ag or ðAg"Htsa#"PPh2#2Ł = CH1Cl1] H\ 3[52^ C\ "9[2)# observed below 049>C with an endothermic
54[63^ O\ 1[71^ P\ 7[19^ S\ 1[72^ Cl\ 5[15^ Ag\ 8[41[ peak at 052>C^ decomposition began at 169>C[ IR
TG:DTA] weight loss of 5[71) observed below 006>C "KBr disk#] n 0571vs\ 0474m\ 0366m\ 0353m\ 0322s\
with an endothermic point at 009>C[ Calc[ for ðAg"Ht! 0395m\ 0298s\ 0154m\ 0137m\ 0988s\ 0942m\ 0925m\
sa#"PPh2#2Ł = xCH1Cl1\ 6[49) "xꢁ0#^ decomposition 886w\ 847w\ 643s\ 583s\ 427s\ 496s\ 385s cm−0[ 0H and

2411
K[ Nomiya et al[
0
02C NMR in CDCl2 are shown in Table 2[ 20P NMR signal at 4[16 ppm observed in H NMR spectra and
"CDCl2# d 26[45 "PPh2#[
by a carbon signal at 42[31 ppm in 02C NMR spectra[
TG:DTA analyses of two independent samples pre!
pared from di}erent starting materials also con_rm
the presence of one solvated CH1Cl1 as the observed
weight loss 5[71 and 6[13) "calc[ 6[49)# with an
endothermic peak at 009 and 093>C\ respectively[
The solid FT!IR spectra "Fig[ 0# of complexes 2 and
3 show a disappearance of the SÐH stretching band
around 1459 cm−0 due to the SH group in the free
H1tsa ligand\ suggesting the metalÐS bond formation[
Also shown is that the carbonyl stretching bands
around 0699 cm−0 are unchanged after complexation\
compared with that of the free H1tsa ligand\ sug!
gesting that the carboxyl group remains protonated
and does not coordinate to the central metal ions[
Many small bands observed in 2999Ð1499 cm−0 region
are also attributed to the presence of a protonated
carboxylic group as usually observed[ Thus\ the IR
spectra of all complexes 2\ 2a and 3 show that the
coordination by the Htsa− ligand to metal centers is
only through the sulfur atom in the mercapto group[
No coordination of the carboxyl oxygen atoms to
the metal is also supported by the X!ray analysis
described later[ It has been also clari_ed by ESCA
measurements of the two thiosalicylatosilver"I# com!
plexes 0 and 1 that even the deprotonated carboxyl
group does not participate in the coordination to the
silver"I# atom ð27Ł[
1[3[ X!ray structural analysis
Crystals of complex 2 were obtained as colorless
needles from a solution of the solvent mixture\ dichlo!
romethaneÐethanol\ and those of 3 as pale yellow
cubes from a solution of dichloromethaneÐacetone[
During a few days| standing at room temperature\
crystals of su.cient quality suitable for single!crystal
X!ray di}raction studies were grown[
Each single!crystal of 2 and 3 was mounted on glass
_ber and transferred to a Rigaku AFC4S di}ract!
ometer[ Cell contents and orientation matrix of 2 and
3 were obtained from the least!squares re_nement of
14 and 12 re~ections\ respectively[ The re~ection data
were collected using vÐ1u scan with graphite!mon!
ochromated MoÐKa radiation at room temperature[
The intensities of three standard re~ections which
were measured after every 049 re~ections remained
constant throughout the data collection[ The data
were corrected for Lorentz and polarization e}ects
and empirical absorption corrections based on PSI
scan were applied to the data[ For the overall averaged
transmission curve\ the transmission factors of 2 and
3 were in the range of 9[82Ð0[99 and 9[12Ð0[99\ respec!
tively[ The structures were solved by direct methods
followed by subsequent di}erence Fourier calculation
and re_ned by a full!matrix least!squares procedure
using TEXSAN package ð45Ł[ For 2\ all atoms except
hydrogen and carbon were re_ned anisotropically[
Carbon and hydrogen atoms were re_ned isotropic!
ally[ For 3\ all atoms except hydrogen were re_ned
anisotropically and hydrogen atoms isotropically[
Crystal data\ data collection and re_nement for 2
and 3 are summarized in Table 0[
2[1[ Synthetic reactions and li`and replacement
The conceptually straightforward\ synthetic reac!
tions of thiosalicylatotris"triphenylphosphine#silver"I#\
which has been herein isolated as 2 without any solvate
and:or as 2a with CH1Cl1 solvate\ are outlined in
equations "0#Ð"2# "Scheme 0#[ On the other hand\ the
synthesis of thiosalicylato"triphenylphosphine#gold"I#
obtained as 3 is shown in equation "5#[
2[ RESULTS AND DISCUSSION
The reactions in equations "1# and "5# exhibit a
2[0[ Molecular formula and compositional charac! simple ligand replacement of the coordinated Cl−
terization
ligand with free H1tsa without change in the coor!
dination number of the starting silver"I# and gold"I#
The composition and molecular formula of 2 which atoms[ In the reaction shown in equation "0#\ the
consists of one silver"I# atom\ one coordinating Htsa− dimeric silver"I# structure with bridged Cl− ligands is
ligand and three PPh2 ligands without any solvated transformed to the monomeric structure by their
molecules\ those of 2a with one solvated CH1Cl1 mol! ligand exchange with free H1tsa\ where the coor!
ecule and those of 3 composed of one gold"I# atom\ dination number of silver"I# remains unchanged[ In
one Htsa− ligand and one PPh2 ligand without any the reaction in equation "2#\ the polymeric structure
solvated molecules are based on elemental analyses with bridged sulfur atoms is changed to the mono!
"in particular for 2a and 3\ all elements including meric structure accompanied with a change in the
oxygen\ 88[36 and 88[27) totals are observed^ see coordination number of the silver"I# atom from 1 to
Section 1#\ TG:DTA and single!crystal X!ray analyses 3[
described later[
From the synthetic reactions in equations "0#Ð"2#\
As to the solvation by one CH1Cl1 molecule in 2a\ the ease of ligand replacement\ i[e[ the relative order!
in the absence of any other sources of chlorine\ the Cl ing of ligand replacement\ is suggested for the for!
analysis "calc[ 5[15\ found 4[64)# re~ects the presence mation of the silver"I# complexes ðAgL"PPh2#nŁm from
of solvated CH1Cl1[ The additional evidence for the the starting complexes ðAgLŁx "LꢁN\ S donor atoms#
presence of solvated CH1Cl1 is provided by a proton and ðAgCl"PPh2#nŁm to be] AgÐP××AgÐS×AgÐCl

Synthesis\ characterization and X!ray crystal structure of ðAg"Htsa#"PPh2#2Ł "H1tsaꢁo!HS"C5H3#CO1H# 2412
Table 0[ Summary of X!ray di}raction data
2 ðAg"Htsa#"PPh2#2Ł
3 ðAu"Htsa#"PPh2#Ł
Formula
MW
C50H49O1P2AgS
0936[80
monoclinic
P10:n "(03#
09[63"0#
13[882"2#
08[735"2#
89
094[29"3#
89
4025"5#
1059
C14H19O1PAuS
501[32
triclinic
Crystal system
Space group
¹
P0"(1#
Ä
a "A#
00[431"2#
01[980"3#
7[649"2#
86[74"2#
096[68"2#
091[33"2#
0097[1"6#
481[99
Ä
b "A#
Ä
c "A#
a ">#
b ">#
g ">#
2
Ä
V "A #
F"999#
Z
3
1
dcalc[ "g = cm−0
#
0[244
0[893
Crystal size "mm#
No[ of re~ections used for
Unit cell dimension "1u range#
Radiation
9[1×9[1×9[1
14
"29[0Ð22[9#
9[1×9[2×9[1
12
"29[1Ð23[4#
Ä
Ä
MoÐKa "lꢁ9[60958 A#
MoÐKa "lꢁ9[60958 A#
Scan mode
1uÐv
1uÐv
Scan width
9[73¦9[29 tan u
05
0[52¦9[29 tan u
21
Scan speed "min−0
#
1u range
5Ð49
4[58
5Ð44
57[05
m "cm−0
#
Total re~ections
6801
4240
Re~ections unique
Re~ections observed
R\ Rw
6281
4988
1032 ðI×1s"I#Ł
9[975\ 9[944
0[47
2112 ðI×2s"I#Ł
9[944\ 9[930
0[78
GOF
RꢁSð=Fo=−=Fc=Ł:S=Fo=\ RwꢁðS"v ð=Fo=−=Fc=Ł1:Sv"=Fo=#1Ł0:1\ with vꢁ3Fo1:ðs1"Fo1#Ł[
and\ from equation "5#\ that for the gold"I# complexes present complexes 2 and 3 could not be exchanged
is also suggested to be] AuÐP××AuÐS×AuÐCl[ On with an alkali metal ion such as sodium ion^ i[e[ neither
the other hand\ the synthetic reactions of the recently {{NaðAg"tsa#"PPh2#2Ł|| nor {{NaðAu"tsa#"PPh2#Ł|| can
found\ metal"I# complexes containing nitrogen!con! be derived by the reactions of aqueous NaOH with 2\
taining heterocycles such as imidazole and triazoles 2a or 3\ respectively[ We found\ or rather\ that the
have indicated that the relative ordering for silver"I# reactions of 2 and 2a with aqueous NaOH resulted
follows AgÐP××AgÐCl×AgÐN××AgÐO\ while that in reproducing the water!soluble\ oligomeric species\
for gold"I# follows] AuÐP××AuÐN×AuÐCl××AuÐ "NaðAg"tsa#Ł#n 0 by a loss of the PPh2 ligands[ Since
O ð30Ð32Ł[ Thus\ we can deduce the relative ligand the polymeric compound 1 can be converted to the
replacement for the silver"I# complexes as AgÐ oligomer 0 by its reaction with aqueous NaOH and 0
P××AgÐS×AgÐCl×AgÐN××AgÐO\ while that for can also be transformed to 1 by its reaction with
the gold"I# complexes\ i[e\ as AuÐP××AuÐS×AuÐ aqueous HCl ð27Ł\ there exists an interconversion
N×AuÐCl××AuÐO[ This information allows us to relationship between 2 and 1 via the oligomer 0 as a
know if target molecules by medicinally or phar! mediator as shown in equations "2#Ð"4# "Scheme 0#[
maceutically active compounds of silver"I# and gold"I#
are proteins containing enzymes as N\O\S!donors or
nucleic acids as N\O!donors of biological ligands[ In 2[2[ Molecular and crystal structures of 2 and 3
fact\ the wide spectra of excellent antibacterial and
antifungal activities found in the ðAg"imd#Łn "Him!
The molecular structures of 2 and 3 were deter!
dꢁimidazole# has been attributed to proteins con! mined with single!crystal X!ray di}raction analysis
taining a sulfur donor atom as the potential target and are shown in Figs 1 and 2\ respectively[ Their
molecule for inhibition of growth of the test organ! selected distances and angles are listed in Table 1[
isms\ but not to nucleic acids without a sulfur donor
ð30\ 31Ł[
The silver atom of 2 is coordinated with three phos!
phorus atoms of the PPh2 ligands and the sulfur atom
The proton attached to the carboxyl group in the of the Htsa− ligand to form a tetrahedral geometry[

2413
K[ Nomiya et al[
Fig[ 0[ Solid FT!IR spectra measured in KBr disks in the 3999Ð399 cm−0 region of "a# free H1tsa ligand\ of "b# ðAg"Ht!
sa#"PPh2#2Ł\ 2\ and of "c# ðAu"Htsa#"PPh2#Ł\ 3[
As found in Table 1\ the angles around the silver atom H3CO1H moiety of 2 planar[ The dihedral angles
deviate from the ideal value of 098[4>[ One SÐAgÐP between the plane C "AgÐSÐC45# and the A or the B
angle is smaller and two of them are greater than are 028> and 32>\ respectively[ The distances between
098[4>[ All PÐAgÐP angles are greater than 098[4>[ the silver and oxygen atoms are 5[69 "AgÐO0#\ 5[73
Ä
The geometries around the silver atoms of the starting "AgÐO0?# and 4[09 "AgÐO1# A[ These angles and dis!
materials ðAgCl"PPh2#2Ł and ðAgCl"PPh2#1Ł1 are also tances indicate that the carboxyl group is directed
tetrahedral ð49\ 40Ł[ Three structures of the silver"I# away from the silver atom[ From the intermolecular
complexes can be compared with each other[ The dis! oxygen distances\ no intermolecular hydrogen bond
tances and angles of 2 are similar to those of between the carboxyl groups of the Htsa− is observed
ðAgCl"PPh2#2Ł\ except longer AgÐS bond vs AgÐCl for 2[ Thus\ the complex 2 is monomeric[
bond\ rather than those of ðAgCl"PPh2#1Ł1[ The
The gold atom in 3 is placed in the linear geometry
dihedral angle between the planes of the carboxyl de_ned by the phosphorus atom of the PPh2 ligand
group "A^ O0\ O1\ C50# and the Htsa− "B^ S0\ C44\ and the sulfur atom of the Htsa−[ The PÐAuÐS angle
C45\ C46\ C47\ C48\ C59# is 065>\ showing the SC5 of 3 is smaller "062[9"0#># than that of the recently

Synthesis\ characterization and X!ray crystal structure of ðAg"Htsa#"PPh2#2Ł "H1tsaꢁo!HS"C5H3#CO1H# 2414
Scheme 0[ Reaction schemes[
reported\ related complex ðAu"Htsa#"PCy2#Ł "PCy2 revealing that an intermolecular hydrogen bond is
ꢁtricylcohexylphosphine# "065[7># ð15Ł[ The AuÐS formed in 3[ This is contrasted with the structure of
Ä
and the AuÐP distances of 3 ""1[181"3#\ 1[159"2# A# 2[ In 3\ two ðAu"Htsa#"PPh2#Ł units are centro!
are slightly shorter than those of ðAu"Htsa#"PCy2#Ł symmetrically associated via the carboxylic moieties
Ä
"1[202"0#\ 1[160"0# A# and they are equal within exper! to form a dimeric unit[ This picture has also been
imental errors to the distances of other gold"I# com! shown in ðAu"Htsa#"PCy2#Ł ð15Ł[
plexes with a PPh2 ligand\ ðAu"1!tu#"PPh2#Ł "1!
Htuꢁ1!thiouracil# "AuÐS 1[185"1# A^ AuÐP 1[299"1#
A# ð29Ł[ This picture may be attributed to the di}er! 2[3[ Solution NMR "0H\ 02C\ 20P and 098Ag# charac!
Ä
ence in cone!angles of the phosphine ligands[ The terization
dihedral angles of the carboxyl group "D^ O1\ O2\ C3#
and the Htsa− "E^ S0\ C4\ C5\ C6\ C7\ C8\ C09#
The 20P NMR spectra measured in CDCl2 at 11>C
is 031>\ indicating some delocalization of p!electron show a single peak due to the coordinating PPh2
density occurs between the SC5H3 and CO1H moieties[ ligands at 3[68 ppm for 2 ðFig[ 3"a#Ł\ at 3[44Ð3[46 ppm
The dihedral angles of the planes of F "AuÐS0ÐC09# for 2a and at 26[45 ppm for 3 ðFig[ 3"c#Ł\ while at
and the D or the E are 37> and 027>\ respectively[ The −4[22 ppm for the free PPh2 ligand[ It is obvious that
Ä
AuÐO2 distance of 3 is 2[10 A\ which is much shorter the coordination of the phosphorus donor atom to the
than that of ðAu"Htsa#"PCy2#Ł ð15Ł[ These angles and metal center signi_cantly in~uences the phosphorus
distances show that the carboxyl group is not directed resonance and the 20P chemical shift also re~ects a
away from the gold atom as seen in ðAu"Htsa#"PCy2#Ł di}erence between silver"I# and gold"I# as the metal
i
−
Ä
"4[09 and 5[24 A#[ The distance of O1ÐO2 of the Htsa
center[
On the other hand\ the 20P NMR ðFig[ 3"b#Ł at
Ä
is 1[45"0# A "a symmetry operation i^ −x\ 0−y\ −z#\

2415
K[ Nomiya et al[
Fig[ 1[ Molecular structure of ðAg"Htsa#"PPh2#2Ł\ 2\ with 49) probability ellipsoids[
Fig[ 2[ Molecular structure of ðAu"Htsa#"PPh2#Ł\ 3\ with 49) probability ellipsoids[

Synthesis\ characterization and X!ray crystal structure of ðAg"Htsa#"PPh2#2Ł "H1tsaꢁo!HS"C5H3#CO1H# 2416
Ä
Table 1[ Selected bond distances "A# and angles "># for the complexes
2 ðAg"Htsa#"PPh2#2Ł
3 ðAu"Htsa#"PPh2#Ł
AgÐS
AgÐP0
P0ÐC0
P0ÐC6
P0ÐC02
S0ÐC45
C44ÐC50
C50ÐO0
C50ÐO0?
C50ÐO1
"O0ÐO0?
SÐAgÐP0
AgÐP0ÐC0
AgÐP0ÐC6
AgÐP0ÐC02
AgÐSÐC45
SÐC45ÐC44
1[597"6#
1[463"6#
0[71"1#
0[73"1#
0[71"1#
0[65"1#
0[36"2#
0[06"3#
0[39"5#
0[17"2#
9[64"5##
81[7"1#
003[1"5#
001[4"6#
007[1"7#
006[3"6#
012"0#
AgÐP1
AgÐP2
1[466"5#
1[500"5#
0[72"1#
0[70"1#
0[70"1#
0[73"1#
0[74"1#
0[70"1#
AuÐS0
1[181"3#
1[159"2#
0[68"0#
0[68"0#
0[73"0#
0[66"0#
0[36"1#
0[29"0#
0[14"0#
AuÐP0
P0ÐC00
P0ÐC06
P0ÐC12
S0ÐC09
C4ÐC3
C3ÐO1
C3ÐO2
P1ÐC08
P1ÐC14
P1ÐC20
P2ÐC26
P2ÐC32
P2ÐC38
SÐAgÐP1
SÐAgÐP2
005[6"1#
097[6"1#
001[9"1#
001[8"1#
001[2"1#
098[1"6#
008[0"6#
004[5"6#
005[6"6#
006[3"5#
001[5"6#
S0ÐAuÐP0
062[9"0#
000[2"3#
002[6"3#
003[9"3#
009[6"3#
015[4"8#
014"0#
005"0#
011"0#
019"0#
AuÐP0ÐC00
AuÐP0ÐC06
AuÐP0ÐC12
AuÐS0ÐC09
S0ÐC09ÐC4
C09ÐC4ÐC3
C4ÐC3ÐO1
C4ÐC3ÐO2
O1ÐC3ÐO2
P0ÐAgÐP1
P0ÐAgÐP2
P1ÐAgÐP2
AgÐP1ÐC08
AgÐP1ÐC14
AgÐP1ÐC20
AgÐP2ÐC26
AgÐP2ÐC32
AgÐP2ÐC38
C45ÐC44ÐC50 013"1#
C44ÐC50ÐO0
C44ÐC50ÐO1
O0ÐC50ÐO1
018"2#
019"1#
009"2#
−89>C measured in CD1Cl1 of 2 showed two signals tion\ because of the monomeric structure of 2 kept in
with equal intensity at 3[89 and 2[15 ppm\ each with solution[ The chemical shift is assignable to a four!
splittings\ which are attributed to a coupling of 20P coordinate silver"I# complex with sulfur and phos!
with 098Ag "Iꢁ0:1# or 096Ag "Iꢁ0:1# nucleus as pre! phorus donor atoms[ This resonance is compared with
viously
observed
in
ðAg"imd#"PPh2#2Ł
ð31Ł\ those of the two!coordinate silver"I# complexes for!
ðAgCl"PPh2#2Ł ð46Ł\ ðAg"dppe#1ŁNO2 "dppeꢁ0\1! med only by the bridged sulfur atom\ previously mea!
bis"diphenylphosphino#ethane# ð47Ł\ ðAg"pz#"PPh2#2Ł sured at room temperature in D1O^ at 744[5 ppm for 0
"Hpzꢁpyrazole#
"Htrizꢁ0\1\2! or 0\1\3!triazole# ð32Ł[ The coupling ð25Ł
ð48Ł
and
ðAg"triz#"PPh2#1Łn ð27Ł and at 757[6 ppm for "NaðAg"Htma#Ł = 9[4H1O##n
"H2tmaꢁthiomalic acid^ HO1CCH!
constants 0J"098AgÐ20P# and 0J"096AgÐ20P# were esti! "SH#CH1CO1H#[ Also\ this chemical shift is compared
mated as 174 and 155 Hz\ respectively\ and the chemi! with those of the averaged single peak due to the
cal shift was as d "20P#ꢁ3[97 ppm[ These data are rapid\ dynamic exchange among unequivalent 098Ag
consistent with those of four!coordinate\ tetrahedral species present in CDCl2 solution at room tem!
complexes included in the above related complexes in perature^ at 0075 ppm for ðAg"imd#"PPh2#2Ł ð31Ł and
solution ð46Ð59Ł[
at 883 ppm for ðAg"0\1\2!triz#"PPh2#1Łn and at 814 ppm
The 20P NMR spectrum of 2 at −89>C consisting for ðAg"0\1\3!triz#"PPh2#1Łn ð32Ł[
of only two major peaks is in contrast to those of the
In 0H and 02C NMR spectra measured in CDCl2 at
related silver"I#ÐN bonding complexes such as 11>C of the complexes 2\ 2a and 3\ four proton and
ðAg"imd#"PPh2#2Ł ð31Ł\ ðAg"pz#"PPh2#2Ł ð48Ł and seven carbon resonances of the coordinating Htsa−
ðAg"triz#"PPh2#1Łn ð32Ł\ all of which have furthermore ligand were completely assigned using several two!
exhibited additional several signals due to various dimensional NMR "0HÐ02C COSY\ 0HÐ02C HMBC
degrees of association in addition to dissociation of and 0HÐ02C HMQC# methods and their chemical shifts
PPh2 and perhaps also of the nitrogen!donor ligands\ are shown in Table 2[
i[e[ due to the dynamic exchange very rapidly in the
NMR timescale[ These results reveal that the four!
coordinate geometry of 2 is kept in solution and the
complex 2 is also present only as a monomeric species
in solution[ Thus\ we conclude that the behavior of 2
in solution is unusually static[
3[ CONCLUSIONS
In conclusion\ the novel complex ðAg"Htsa#
"PPh2#2Ł\ 2\ as a monomeric form of the oligomeric
098Ag NMR spectra in CDCl2 measured at 11>C or polymeric silver"I# thiosalicylates 0 or 1 showing
exhibit only one resonance at 0085 ppm for 2a\ also e}ective antimicrobial activities\ has been isolated in
suggesting that only a single species is present in solu! good yield and also as its CH1Cl1 solvate\ 2a[ These

2417
K[ Nomiya et al[
Fig[ 3[ 20P"0H# NMR spectra measured with reference to an external 14) H2PO3 of ðAg"Htsa#"PPh2#2Ł\ 2\ measured "a# in
CDCl2 at 11>C and "b# in CD1Cl1 at −89>C and of "c# ðAu"Htsa#"PPh2#Ł\ 3\ measured in CDCl2 at 11>C[
Table 2[ Assignment of 0H and 02C NMR signals of thiosalicylatometal"I# complexesa
0H NMR
Ha
Hd
Hc
Hb
ðAg"Htsa#"PPh2#2Ł
ðAg"Htsa#"PPh2#2Ł = CH1Cl1
ðAu"Htsa#"PPh2#Ł
H1tsa
2
2a
3
7[03
7[04
7[22
7[93
6[12b
6[08b
6[62
6[52
5[51
5[45
6[29
6[24
5[71
5[79
6[10
6[46
02C NMR
C0
C1
C2
C3
C4
C5
C6
ðAg"Htsa#"PPh2#2Ł
ðAg"Htsa#"PPh2#2Ł = CH1Cl1
ðAu"Htsa#"PPh2#Ł
H1tsa
2
2a
3
021[33
021[42
022[06
017[00
029[09
029[06
020[20
027[82
038[08
037[70
027[62
022[12
025[74
025[76
026[45
014[99
029[47
029[54
020[40
020[43
011[19
011[35
014[64
014[86
069[90
058[66
056[87
056[48
0
aBoth H and 02C NMR spectra of 2\ 2a and 3 were measured in CDCl2 at 11>C with reference to an internal TMS and
those of free ligand H1tsa measured in DMSO!d5[ The assignment of the chemical shifts was based on the 1D!NMR "COSY\
HMBC and HMQC# methods[
bThese signals were overlapped with the PPh2 multiplet signals[

Synthesis\ characterization and X!ray crystal structure of ðAg"Htsa#"PPh2#2Ł "H1tsaꢁo!HS"C5H3#CO1H# 2418
05[ Hill\ D[ T[ and Sutton\ B[ M[\ Cryst[ Struct[ Com!
mun[\ 0879\ 8\ 568[
06[ Vicente\ J[\ Chicote\ M[!T[\ Gonzalez!Herrero\ P[
and Jones\ P[ G[\ J[ Chem[ Soc[ Dalton Trans[\
0883\ 2072[
07[ Bowmaker\ G[ A[ and Dobson\ B[ C[\ J[ Chem[
Soc[ Dalton Trans[\ 0870\ 156[
08[ Bates\ P[ A[ and Waters\ J[ M[\ Acta Crsytallo`r[
C\ 0874\ 30\ 751[
19[ Beck\ W[\ Stetter\ K[ H[\ Tadros\ S[ and Sch!
warzhans\ K[ E[\ Chem[ Ber[\ 0856\ 099\ 2833[
10[ Vicente\ J[\ Chicote\ M[!T[\ Saura!Llamas\ I[ and
Lagunas\ M[ C[\ J[ Chem[ Soc[ Chem[ Commun[\
0881\ 804[
11[ Schroter\ I[ and Strahle\ J[\ Chem[ Ber[\ 0880\ 013\
1050[
12[ Cookson\ P[ D[ and Tiekink\ E[ R[ T[\ J[ Chem[
Soc[ Dalton Trans[\ 0882\ 148[
13[ Cookson\ P[ D[ and Tiekink\ E[ R[ T[\ J[ Crys!
tallo`r[ Spectrosc[ Res[\ 0882\ 12\ 120[
14[ Isab\ A[ A[\ Hormann\ A[ L[\ Hill\ D[ T[\ Gris!
wold\ D[ G[\ DiMarino\ M[ J[ and Shaw\ C[ F[\
Inor`[ Chem[\ 0878\ 17\ 0210[
complexes\ 2 and 2a\ have been derived from three
di}erent ligand!exchange reactions[ The inter!
conversion relationship among three thiosalicylato!
silver"I# complexes\ 0\ 1 and 2 was clari_ed[ The cor!
responding gold"I# analog\ ðAu"Htsa#"PPh2#Ł\ 3\ was
also isolated[ From a synthetic viewpoint\ the relative
ordering of ligand replacement in the silver"I# com!
plexes was found to be] AgÐP××AgÐS×AgÐCl×AgÐ
N\ while that in the gold"I# complexes followed AuÐ
P××AuÐS×AuÐN×AuÐCl[ The crystal structures of
2 and 3 were determined with single!crystal X!ray
di}raction\ suggesting the monomeric structure of 2
and the dimeric structure of 3 in the solid state[ All
complexes obtained have been fully characterized with
complete elemental analyses\ TG:DTA\ FT!IR and
multinuclear "0H\ 02C\ 20P and 098Ag# NMR spec!
troscopies[ In particular\ it was found that the mono!
meric\ 3!coordinate geometry of 2 was kept in
solution[
Acknowled`ements*Financial support from Meiji Cell
Technology Center\ Meiji Milk Products Co[ is gratefully 15[ Cookson\ P[ D[ and Tiekink\ E[ R[ T[\ J[ Coord[
acknowledged[
Chem[\ 0881\ 15\ 202[
16[ Harker\ C[ S[ W[\ Tiekink\ E[ R[ T[ and White!
house\ M[ W[\ Inor`[ Chim[ Acta\ 0880\ 070\ 12[
17[ Tiekink\ E[ R[ T[\ Cookson\ P[ D[\ Linahan\ B[
M[ and Webster\ L[ K[\ Metal Based Dru`s\ 0883\
0\ 188[
18[ Girard\ G[ R[\ Hill\ D[ T[ and DiMartino\ M[ J[\
Inor`[ Chim[ Acta\ 0878\ 055\ 030[
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