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Article

Reactivity of Mononuclear and Dinuclear Gold(I) Amidinate Complexes with CS2 and CsBr3

by
Andrew C. Lane
,
Charles L. Barnes
,
Matthew V. Vollmer
and
Justin R. Walensky
*
Department of Chemistry, University of Missouri, Columbia, MO 65211-7600, USA
*
Author to whom correspondence should be addressed.
Inorganics 2014, 2(4), 540-551; https://doi.org/10.3390/inorganics2040540
Submission received: 20 August 2014 / Revised: 10 September 2014 / Accepted: 11 September 2014 / Published: 8 October 2014
(This article belongs to the Special Issue Frontiers in Gold Chemistry)
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Abstract

:
To probe the reactivity of gold-nitrogen bonds, we have examined the insertion chemistry with carbon disulfide (CS2) as well as oxidation with cesium tribromide (CsBr3) with Au(I) amidinate complexes. The reaction of Ph3PAuCl with Na[(2,6-Me2C6H3N)2C(H)] yields the mononuclear, two-coordinate gold(I) complex, Ph3PAu[κ1-(2,6-Me2C6H3N)2C(H)], 1. The reactivity of 1 with CS2 produced the mononuclear Au(I) compound, Ph3PAu{κ1-S2C[(2,6-Me2C6H3N)2C(H)]}, 2. In the case of CsBr3 the previously reported dinuclear Au(I) complex, Au[(2,6-Me2C6H3N)2C(H)]2, 3, was isolated with formation of Ph3PBr2. We also compared the reactivity of CS2 and CsBr3 with 3. Carbon disulfide insertion with 3 produces a dimeric product, Aun[CS2(2,6-Me2C6H3NC(H)=NC6H3Me2)]n, 4, featuring a dinuclear core with linking aurophilic interactions, making it appear polymeric in the solid state. When CsBr3 is reacted with 3 the Au(II,II) product is obtained, Au2[(2,6-Me2C6H3N)2C(H)]2(Br)2, 5.

1. Introduction

The chemistry of gold is dominated by soft donor ligands due to the propensity for gold to form stronger interactions with elements such as phosphorus and sulfur. Hence, gold-nitrogen bonds are uncommon [1] and the reactivity of these bonds is relatively unexplored [2]. With the recent advances in gold amidinate chemistry [3], we sought to develop this reactivity by examining insertion and oxidative chemistry in Au(I) amidinate complexes.
Di- [4,5,6], tri- [4], and tetranuclear [7,8,9,10] gold amidinate complexes have been isolated, but to our knowledge, only one mononuclear gold complex has been reported [11]. However, that compound contains a protonated amidine ligand. The oxidative chemistry of dinuclear Au(I) amidinate complexes is characterized by a two-electron redox process with one-electron being produced from each Au(I) center to create Au(II,II) amidinate complexes, and maintains its dinuclear core. For example, reactions of PhICl2, Br2, and I2 with Au2[(2,6-Me2C6H3N)2C(H)]2 produce Au2[(2,6-Me2C6H3N)2C(H)]2(X)2, X = Cl, Br, and I [5], respectively, Equation (1).
Inorganics 02 00540 i001
While the redox chemistry of these species has been observed, no insertion chemistry has been explored which affords the opportunity to expand to polymetallic complexes. Carbon disulfide (CS2) was chosen due to group 11 metals’ preference for soft donor atoms. The insertion chemistry of carbon disulfide with gold has been demonstrated with Au–C [12,13], Au–Cl [14], and Au–S [15] bonds.
In addition to soft donor ligands, gold chemistry is influenced by aurophilic interactions [16,17,18] in which the distance between two gold atoms is less than the sum of their van der Waals radii. These interactions can be quite strong and affect the coordination chemistry and chemical properties of gold [19,20,21].
The synthetic route to Au2[(2,6-Me2C6H3N)2C(H)]2 is the reaction of (tht)AuCl with Na[(2,6-Me2C6H3N)2C(H)]; however, we surmised that by starting with Ph3PAuCl, the preference for Au(I) to form two-coordinate, linear complexes would allow for the isolation of a mononuclear species. The [Ph3PAu]+ fragment can be viewed as isolobal to H+ [22,23] and this moiety has been extensively studied [24]. We report here the synthesis of the two-coordinate, linear Ph3PAu[κ1-(2,6-Me2C6H3N)2C(H)] and have investigated its insertion chemistry with CS2 as well as attempted oxidation with CsBr3. The analogous reactions with the dinuclear compound, Au2[(2,6-Me2C6H3N)2C(H)]2, were also performed for comparison.

2. Results and Discussion

The amidine ligand is deprotonated with NaN(SiMe3)2 and allowed to stir for approximately one hour before addition of Ph3PAuCl therefore we do not anticipate the formation of Ph3PAuN(SiMe3)2 [25]. Reaction of Ph3PAuCl with Na[(2,6-Me2C6H3N)2C(H)] does not form the dinuclear gold product that is formed with (tht)AuCl, Equation (2).
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Instead, a different 1H NMR spectrum was obtained which showed an asymmetric amidinate environment and had a 31P NMR signal at 35.8 ppm in benzene-d6. This species is sparingly soluble in diethyl ether from which a saturated solution yielded colorless crystals suitable for X-ray diffraction analysis. The structure revealed the two-coordinate Au(I) complex, Ph3PAu[(2,6-Me2C6H3N)2C(H)], 1, Figure 1. The Au–P and Au–N bond distances of 2.2297(4) and 2.0331(4) Å, respectively, are typical for a phosphine and amide coordinated to a Au(I) center, Table 1. For example, the Au–N bond lengths in IPrAuNiPr2 [26] (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) and [Au(HF)(HY)]PF6 (HF = [(2,6-Me2C6H3N)C(H)(2,6-Me2C6H3N(H)]; HY = diphenylmethylmethylene-substituted phorphorus ylide) are 1.967(4) and 2.069(8) Å, respectively [27].
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Figure 1. Thermal ellipsoid plot of 1 shown at the 50% probability level. The hydrogen atoms have been omitted for clarity.
Figure 1. Thermal ellipsoid plot of 1 shown at the 50% probability level. The hydrogen atoms have been omitted for clarity.
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We then turned our attention to the reactivity of 1. The reaction of 1 with CS2 produced a color change from colorless to yellow, Equation (3).
Inorganics 02 00540 i003
The 1H NMR spectrum revealed an asymmetric ligand environment with two different methyl resonances and a new 31P NMR resonance at 36.6 ppm. Due to the decreased solubility in arene solvents, the 1H NMR spectrum was obtained in CDCl3. The proton on the formamidinate backbone shifted downfield to 9.64 ppm, which is in the region observed when a localized imine bond is formed instead of a delocalized bond over the N–C–N backbone. Additional evidence of this was detected in the IR spectrum with a shift from 1605 cm−1 for the NCN stretch in 1 to 1646 cm−1 to a C=N stretch. Yellow crystals of Ph3PAu[κ1-CS2(2,6-Me2C6H3NC(H)=NC6H3Me2)], 2, Figure 2, were obtained from a saturated diethyl ether solution, and a two-coordinate species is also observed with the insertion of CS2 into the Au–N bond and formation of the dithiocarbamate. Similar to 1, the Au–P bond distance is 2.2581(2) Å and the Au–S bond distance of 2.3247(2) Å is typical for Au(I) dithiocarbamates. For reference, the Au–S bond distances in (IPr)Au(S2CNEt2) and (IPr)Au[S2CN(CH2Ph)2], IPr = 1,3-bis(2,6-diisopropylphenyl)imidazole-2-ylidene, are 2.314(5) and 2.2999(12) Å, respectively [27], and 2.312(3) Å in Ph3PAu(indazol-1-yldithiocarbamate) [28].
Table
Table 1. Selected bond lengths (Å) and angles (°) for complex 4.
Table 1. Selected bond lengths (Å) and angles (°) for complex 4.
Bond Distance/Angle4
Au1–S12.31240(5)
Au1–S32.30871(5)
Au2–S22.2789(7)
Au2–S42.2888(7)
Au3–S52.3051(7)
Au3–S72.2900(7)
Au4–S62.2869(7)
Au4–S82.2996(7)
Au1–Au22.76154(5)
Au2–Au33.00745(7)
Au3–Au42.75717(19)
S1–C18–S2128.6153(11)
S3–C38–S4126.9985(11)
S4–Au2–Au389.8335(15)
S2–Au2–Au390.5685(15)
With the recent use of CsBr3 to oxidize Au(I) to Au(III), we attempted a similar reaction with 1 [29]. Indeed, reaction of 1 with CsBr3 is accompanied by a color change to red-brown; however, upon workup the 1H NMR spectrum revealed the presence of the dinuclear Au(I) amidinate, Au2[(2,6-Me2C6H3N)2C(H)]2, 3, as well as resonances consistent with Ph3PBr2, Equation (4). Further, the 31P NMR spectrum also confirmed the phosphorus-based product as Ph3PBr2 [30]. The red-brown color may be due to the possible formation of Au2[(2,6-Me2C6H3N2)C(H)]2(Br)2 which has been previously reported [5]. We rationalize that the products of this reaction result from the precipitation of CsBr, formation of the stronger P-Br bonds rather than Au-Br, and subsequent aurophilic interaction that arises.
Inorganics 02 00540 i004
Inorganics 02 00540 g002 1024
Figure 2. Thermal ellipsoid plot of 2 shown at the 50% probability level. The hydrogen atoms have been omitted for clarity.
Figure 2. Thermal ellipsoid plot of 2 shown at the 50% probability level. The hydrogen atoms have been omitted for clarity.
Inorganics 02 00540 g002
The reactivity of dinuclear Au(I) amidinate complex, Au2[(2,6-Me2C6H3N)2C(H)]2, 3, has not been reported with CS2 or CsBr3 and, therefore, we attempted these substrates to compare with the mononuclear species. Reaction of 3 with CS2 in THF gave a color change to yellow, and, over time, a red solid precipitated. The 1H NMR spectrum showed an asymmetric ligand environment with two distinct methyl resonances and a downfield shift of the formamidinate backbone proton to 9.25 ppm. The IR spectrum also revealed an imine stretch at 1648 cm−1. The product is soluble in chloroform and THF, forming a yellow solution but then slowly precipitates as a red solid. Red crystals were obtained from a heated saturated THF solution and allowed to cool to room temperature, and showed the structure, {Au2[CS2(2,6-Me2C6H3NC(H)=NC6H3Me2)]2}n, 4, Figure 3. Interestingly, 4 has a dinuclear core, Figure 4, with one CS2 inserting into one Au–N bond. The Au–Au bond distances within each molecule are 2.76154(5) and 2.75717(19) Å, and are much shorter than the 3.00745(7) Å aurophilic interaction that links the two dinuclear fragments, Table 1. Over time, aurophilic interactions, which have comparable strength to a hydrogen bond, start to form which could account for the solubility issues and precipitation from solution. The stacking of discrete dimeric units in the solid-state is not new in gold dithiocarbamate chemistry [28,31,32,33,34,35].
Inorganics 02 00540 g003 1024
Figure 3. Thermal ellipsoid plot of 4 shown at the 50% probability level. Hydrogen atoms have been omitted for clarity.
Figure 3. Thermal ellipsoid plot of 4 shown at the 50% probability level. Hydrogen atoms have been omitted for clarity.
Inorganics 02 00540 g003
Inorganics 02 00540 g004 1024
Figure 4. Thermal ellipsoid plot of two units of 4 shown at the 50% probability level. Hydrogen atoms have been omitted for clarity.
Figure 4. Thermal ellipsoid plot of two units of 4 shown at the 50% probability level. Hydrogen atoms have been omitted for clarity.
Inorganics 02 00540 g004
The reaction of 3 with CsBr3 produced a dark brown colored solution and the 1H NMR spectrum showed the formation of the previously reported Au2[(2,6-Me2C6H3N2)C(H)]2(Br)2, 5, albeit in low yield. While the mononuclear product afforded the oxidative addition product, 3 produces a one-electron oxidation from both metal centers yielding two Au(II) centers. This difference in reactivity demonstrates the stability of the amidinate ligand framework in the dinuclear system. Substrates such as PhNCO and CO2 do not insert into the amidinate framework, presumably due to the stability of the dinuclear core, as well as the preference of gold for soft donor atoms, not hard atoms, such as oxygen.

3. Experimental Section

3.1. General Considerations

Even if air-stable, the syntheses described were carried out under inert atmosphere (N2) using glove box or standard Schlenk techniques unless otherwise noted. Solvents were distilled under nitrogen and kept over drying sieves. NaN(SiMe3)2, anhydrous carbon disulfide (Aldrich, Milwaukee, WI, USA) and Ph3PAuCl (Strem, Newportbury, MA, USA) were used as received. The amidine ligand, [(2,6-Me2C6H3N)C(H)(2,6-Me2C6H3N(H)] [36], Au2[(2,6-Me2C6H3N)2C(H)]2, 3 [4], and CsBr3 [29] were prepared as previously described. Benzene-d6 and chloroform-d1 (Cambridge Isotope Laboratories, Tewksbury, MA, USA) were dried over molecular sieves and degassed with three freeze-evacuate-thaw cycles. All 1H, 13C, and 31P NMR data were obtained on a 300 MHz DRX or 500 MHz DRX Bruker (Madison, WI, USA) spectrometer. Infrared spectra were recorded as KBr pellets on Perkin-Elmer (Waltham, MA, USA) Spectrum One FT-IR spectrometer.

3.2. Synthesis of Ph3PAu[κ1-(2,6-Me2C6H3N)2C(H)], 1

NaN(SiMe3)2 (145 mg, 0.792 mmol) was added to a stirred solution of [(2,6-Me2C6H3N)C(H)(2,6-Me2C6H3N(H)] (200 mg, 0.792 mmol) in THF (15 mL). After 1 h, Ph3PAuCl (391 mg, 0.791 mmol) was added and allowed to stir for 12 h. Insoluble material was removed via centrifugation and filtered through Celite. The solvent was then removed under vacuum to give yield 1 as a white powder (153 mg, 68%). Colorless X-ray quality crystals were grown overnight from a saturated diethyl ether solution at −35 °C. 1H NMR (C6D6, 500 MHz): δ 7.4 (buried in multiplet, 1H, CH), 7.5 (m, PPh3), 7.45 (m, PPh3), 7.43 (m, PPh3), 7.25 (t, 3JH–H = 7.5 Hz, 1H, Ph), 7.07 (t, 3JH–H = 7.5 Hz, 2H, Ph), 6.9 (t, 3JH–H = 7.5 Hz, 1H, Ph), 6.5 (d, 3JH–H = 7.5 Hz, 1H, Ph), 2.42 (s, 6H, Me), 2.17 (s, 6H, Me). 13C NMR (CD3CN, 126 MHz): δ 155 (CH), 135 (Ph), 134 (PPh3), 131 (Ph), 130 (PPh3), 129.8 (PPh3), 129.5 (Ph) 129 (Ph) ppm. 31P NMR (CDCl3, 101MHz): δ 35.8 ppm. IR (KBr): 3060 (w, C–H), 3006 (C–H), 2961 (w (br), C–H), 2938 (m, C–H), 2904 (w (br), C–H), 1605 (s, C–N), 772 (m, P–C) cm−1. Anal. Calcd. for C35H35N2PAu: C, 59.16%; H, 4.82%; N, 3.94%. Found: C, 58.62%; H, 4.73%; N, 3.69%.

3.3. Synthesis of Ph3PAu[κ1-CS2(2,6-Me2C6H3NC(H)=NC6H3Me2)], 2

To a stirred solution of 1 (100 mg, 0.143 mmol) in THF (15 mL), excess carbon disulfide (CS2) was added. The solution immediately turned yellow upon addition. After 1 h, the solvent was then removed under vacuum to yield 2 as a yellow powder (48 mg, 47%). Transparent yellow crystals suitable for X-ray diffraction analysis formed from a yellow solution of diethyl ether solution at −35 °C. 1H NMR (500 MHz, CDCl3): δ 9.64 (s, 1H, CH), 7.63–7.42 (m, 15 H, PPh3), 7.18 (d, 3JH–H = 7.6 Hz, 2H, Ph), 6.99 (d, 3JH–H = 7.6 Hz, 2H, Ph), 6.87 (t, 3JH–H = 7.6 Hz, 1H, Ph), 2.38 (s, 6H, Me), 2.13 (s, 6H, Me) ppm. 13C NMR (126 MHz, CDCl3): δ 215.88 (quat), 150.65 (CH), 148.15 (Ph), 139.66 (Ph), 135.58 (Ph), 134.26–134.42 (Ph), 134.18 (Ph), 131.56 (Ph), 129.85 (Ph), 129.39 (Ph), 129.09 (Ph), 128.60 (Ph), 128.03 (Ph), 127.90 (Ph), 123.32 (Ph), 18.82 (Me), 18.00 (Me) ppm. 31P NMR (101 MHz, CDCl3): δ 36.6 ppm. IR (KBr): 3046 (w, C–H bending), 2968 (w (br), C–H bending), 2918 (w (br), C–H bending), 1646 (s, C=N stretch), 774 (m, P–C stretch) cm−1. Anal. Calcd. for C36H34N2PS2Au: C, 54.96%; H, 4.36%; N, 3.56%. Found: C, 54.89%; H, 4.62%; N, 3.40%.

3.4. Au2[(2,6-Me2C6H3N)2C(H)]2, 3, from 1 and CsBr3

To a stirred solution of Ph3PAu[(2,6-Me2C6H3N)2C(H)], 1, (100 mg, 0.141 mmol) was added CsBr3 (52 mg, 0.141 mmol) in THF (12 mL). The solution changed from a colorless to a dark red/brown solution. Off-white precipitate crashed out after stirring for 1 h. The 31P NMR spectrum of this off-white solid was identified as Ph3PBr2 and the 1H NMR spectrum showed the previously reported Au2[(2,6-Me2C6H3N)2C(H)]2, 3 [4].

3.5. Synthesis of Au2[CS2(2,6-Me2C6H3NC(H)=NC6H3Me2)]2, 4

To a stirred solution of 3 (114 mg, 0.128 mmol) in 15 mL of diethyl ether was added an excess amount of CS2 (~0.1 mL). The solution color immediately changed from colorless to yellow and precipitation began. After 1 h, the solvent was removed yielding 4 as a red solid (66 mg, 45%). Red crystals suitable for X-ray diffraction analysis were obtained by heating a saturated THF solution and slowly cooling to room temperature. 1H NMR (C6D6, 500 MHz): δ 2.05 (s, 12H, Me), 2.27 (s, 12H, Me), 6.86 (t, 3JH–H = 7.5 Hz, 1H, Ph), 6.95 (d, 3JH–H = 7.5 Hz, 2H, Ph), 7.14 (d, 3JH–H = 7.5 Hz, 2H, Ph), 7.20 (m, Ph), 9.25 (s, 1H, CH). 13C NMR (C6D6, 500 MHz): 214.5 (CS2) 149.0 (methine), 146.5 (quat), 140.0 (quat), 135.7 (methine), 129.5 (quat), 129.0 (Ph), 128.5 (Ph), 128 (Ph), 125.4 (quat), 19.0 (CH3), 18.2 (CH3). IR (KBr): 3473 (s), 3156 (s), 2947 (s), 2426 (s), 1766 (vs) 1648 (m), 1589 (s) 1384 (s), 1266 (vs), 1185 (vs), 764 (m) cm−1. Elem. Anal. Calcd. for C36H38N4S4Au2: C, 41.22%; H, 3.65%; N, 5.34%. Found: C, 40.75%; H, 3.78%; N, 5.09%.

3.6. Synthesis of Au2[(2,6-Me2C6H3N)2C(H)]2(Br)2, 5

To a stirred solution of Au2[(2,6-Me2C6H3N)2C(H)]2 (100 mg, 0.111 mmol), 3, in THF (10 mL), CsBr3 (41 mg, 0.110 mmol) was added. The solution immediately turned from colorless to dark brown with the formation of a precipitate. The solution was filtered through Celite and the solvent removed under vacuum to yield 5 as a dark brown powder (40 mg, 34%). The 1H NMR spectrum confirmed the product as the previously reported, Au2[(2,6-Me2C6H3N)2C(H)]2(Br)2 [5].

3.7. X-ray Crystallography Details.

A selected single crystal of 1, 2, and 4 was mounted on nylon cryoloops using viscous hydrocarbon oil. X-ray data collection was performed at 100(2) or 173(2) K. The X-ray data were collected on a Bruker (Madison, WI, USA) CCD diffractometer with monochromated Mo-Kα radiation (λ = 0.71073 Å) with data collection and processing using the Bruker Apex2 suite of programs [37]. The structures were solved using direct methods and refined by full-matrix least-squares methods on F2 using Bruker SHELEX-97 program [38]. All non-hydrogen atoms were refined with anisotropic displacement parameters and all hydrogen atoms were added on idealized positions and not allowed to vary. Thermal ellipsoid plots were prepared by using X-seed [39] at the 50% probability level for non-hydrogen atoms. Crystal data and detail for data collection for complex 1, 2, and 4 is provided in Table 2.
Table
Table 2. X-ray crystallographic data is shown for complexes 1, 2, and 4.
Table 2. X-ray crystallographic data is shown for complexes 1, 2, and 4.
Compound124
CCDC deposit number101305410130561008664
Empirical formulaC35H34N2PAuC38H39N2S2PO0.50AuC36H38N4S4Au2
Formula weight (g/mol)710.58823.772097.75
Crystal habit, colorColorless, plateYellow, plateRed, prism
Temperature (K)173(2)100(2)100(2)
Space groupP-1C2/cP-1
Crystal systemTriclinicMonoclinicTriclinic
Volume (Å3)2993.8(11)7085.0(7)3629.30(16)
a (Å)10.641(2)38.566(2)8.3937(2)
b (Å)14.542(3)8.7877(5)15.4728(4)
c (Å)20.465(4)27.0810(17)29.2585(8)
α (˚)83.247(2)9099.1330(10)
β (˚)78.545(2)129.4690(10)96.0620(10)
γ (˚)75.244(2)90102.1610(10)
Z482
Calculated density (Mg/m3)1.5771.5451.920
Absorption coefficient (mm−1)4.9934.34617.373
Final R indices [I > 2σ(I)]R1 = 0.0236R1 = 0.0233R1 = 0.0183
wR2 = 0.0498wR2 = 0.0508wR2 = 0.0427

4. Conclusions

A rare mononuclear gold(I) amidinate complex has been synthesized from reaction of Ph3PAuCl with Na[(2,6-Me2C6H3N)2C(H)], and its reactivity explored with CS2 and CsBr3. Addition of CS2 to Ph3PAu[κ1-(2,6-Me2C6H3N)2C(H)] results in the facile insertion into the gold-nitrogen bond to produce the dithiocarbamate species which was also found to also be two-coordinate. The reaction of CsBr3 with Ph3PAu[κ1-(2,6-Me2C6H3N)2C(H)] led to the formation of Ph3PBr2 and the dinuclear amidinate complex, Au2[(2,6-Me2C6H3N)2C(H)]2. For comparison, the dinuclear gold amidinate complex was examined with CS2 and CsBr3. Carbon disulfide also inserted into the gold-nitrogen bonds of Au2[(2,6-Me2C6H3N)2C(H)]2 which maintained its dinuclear form but polymerized through aurophilic interactions between neighboring fragments in the solid-state. The CsBr3, oxidation did occur to the form the dinuclear Au(II,II) product, Au2[(2,6-Me2C6H3N)2C(H)]2(Br)2. The objective of this work was to examine the reactivity of a mononuclear gold(I) amidinate complex, which led to the comparison with the dinuclear gold(I) compound. Our results further demonstrate the tendency for gold to form aurophilic interactions as well as bonds with softer ligands, even when in a dinuclear framework.

Acknowledgments

We gratefully acknowledge the University of Missouri College of Arts and Science Alumni Organization Faculty Incentive Grant for support of this work.

Author Contributions

Andrew C. Lane and Justin R. Walensky conceived and designed the synthetic experiments and wrote the manuscript. Matthew V. Vollmer assisted with experimental design and crystallography. Charles L. Barnes carried out the crystallographic analysis.

Conflicts of Interest

The authors declare no conflict of interest.

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MDPI and ACS Style

Lane, A.C.; Barnes, C.L.; Vollmer, M.V.; Walensky, J.R. Reactivity of Mononuclear and Dinuclear Gold(I) Amidinate Complexes with CS2 and CsBr3. Inorganics 2014, 2, 540-551. https://doi.org/10.3390/inorganics2040540

AMA Style

Lane AC, Barnes CL, Vollmer MV, Walensky JR. Reactivity of Mononuclear and Dinuclear Gold(I) Amidinate Complexes with CS2 and CsBr3. Inorganics. 2014; 2(4):540-551. https://doi.org/10.3390/inorganics2040540

Chicago/Turabian Style

Lane, Andrew C., Charles L. Barnes, Matthew V. Vollmer, and Justin R. Walensky. 2014. "Reactivity of Mononuclear and Dinuclear Gold(I) Amidinate Complexes with CS2 and CsBr3" Inorganics 2, no. 4: 540-551. https://doi.org/10.3390/inorganics2040540

APA Style

Lane, A. C., Barnes, C. L., Vollmer, M. V., & Walensky, J. R. (2014). Reactivity of Mononuclear and Dinuclear Gold(I) Amidinate Complexes with CS2 and CsBr3. Inorganics, 2(4), 540-551. https://doi.org/10.3390/inorganics2040540

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