Synthesis and structural characterization of indium thiolates

Abstract

Homoleptic indium thiolates [$In(SR)_4]^-$ are readily prepared by the reaction of $InCl_3$ and NaSR in methanol and isolated by countercations to produce microcrystalline complexes $[In(SR)_4]Q (Q = NMe_4,\;\;R = C_6H_3-2,\;\;6-Me_2(1)$; $Q = NMe_4,\;\;R = C_6H_5(2);Q = P(C_6H_5)_3Me,\;\;R = C_6H_5(3)$; $Q = P(C_6H_5)_4,\;\;R = C_6H_5(4)).\;\;[In(SPh)_4]^-$ further reacts with elemental sulfur to give crystalline indium sulfidothiolate complexes whose empirical formulae were induced as $[In_2S_3(SPh)]Q (Q = NMe_4(5),\;\;Q = P(C_6H_5)_3Me(6))$ from spectroscopic data. The structure of $(Me_4N)[In(SC_6H_3-2,6-Me_2)_4](1)$ has been determined by X-ray crystallography. It crystallizes in the monoclinic space group $P2_1$/n with the following unit cell dimensions; a = 10.894 $\mbox{\AA}$, b = 19.313 $\mbox{\AA}$, c = 17.393$\mbox{\AA}$, $\beta$ = 91.74$^\circ\!$, V = 3657.7 $\mbox{\AA}^3$ and Z = 4. The structure was refined to convergence, leading to R and R$_W$ of 0. 0379 and 0.0412, respectively, for 4483 observations in the range $2^\circ < 2\theta < 50^\circ$. Average bond length of In-S is 2.464$\mbox{\AA}$. Details of synthesis and other spectroscopic data of the homoleptic indium tetrakisthiolates and indium sulfidothiolates are discussed.