Insertion of CS₂into the Mg–H bond: synthesis and structural characterization of the magnesium dithioformate complex, [Tism^PriBenz]Mg(κ²-S₂CH)

Abstract

The tris[(1-isopropylbenzimidazol-2-yl)dimethylsilyl]methyl magnesium hydride compound, [TismPriBenz]MgH, undergoes insertion of CS2 into the Mg-H bond at room temperature to give [TismPriBenz]Mg(κ2-S2CH), the first structurally characterized magnesium dithioformate compound. The dithioformate complex [TismPriBenz]Mg(κ2-S2CH) reacts with (i) CO2 at 80 °C to give, inter alia, the formate counterpart, [TismPriBenz]Mg(κ2-O2CH), and (ii) Me3SiX (X = Cl, Br), Me3SnX (X = F, Cl, Br) and MeI to afford the halide derivatives, [TismPriBenz]MgX.

Molecular Main Group Metal Hydrides

“…The selectivity of the catalytic system could be controlled by the identity of the silane, with PhSiH 3 favoring CH 4 while the Ph 3 SiH reaction was arrested at the bis­(silyl)­acetal, H 2 C­(OSiPh 3 ) 2 . Compound 140 has also been shown to undergo insertion of CS 2 into the Mg–H bond at room temperature . This reaction provided [( iPr/Benz Tism)­Mg­(κ 2 -S 2 CH)] ( 185 ), the first structurally characterized magnesium dithioformate compound.…”

Metal-Tuned Ligand Reactivity Enables CX2 (X = O, S) Homocoupling with Spectator Cu Centers

“… A similar 13 C NMR experiment performed at −80 °C with 4.0 mM [K­(THF) 3 ]·1 , and 2.3 equiv 13 CS 2 revealed a signal at 231.9 ppm, which is suggestive of the formation of a dithiocarboxylate (Figure S12). − …”

Synthesis, Structure, and Reactivity of a Terminal Cadmium Hydride Compound, [κ3-TismPriBenz]CdH

“…As observed for the formate derivative, [Tism Pr i Benz ]Cd(κ 1 -O 2 CH), the dithioformate complex also exhibits unidentate 52 coordination of the dithioformate ligand, which is noteworthy because the magnesium counterpart [Tism Pr i Benz ]Mg(κ 2 -S 2 CH) adopts a bidentate coordination mode. 51 Spectroscopically, [Tism Pr i Benz ]Cd(κ 1 -O 2 CH) and [Tism Pr i Benz ]Cd(κ 1 -S 2 CH) are characterized by signals at δ 9.53 ppm and δ 11.84 ppm in the 1 H NMR spectra, both of which exhibit satellites due to coupling to 111 Cd and 113 Cd nuclei, with the 3 J 111 Cd−H and 3 J 113 Cd−H coupling constants for the formate (84 and 88 Hz) being larger than the respective values for the dithioformate (80 and 84 Hz). As observed for other pairs of formate and dithioformate compounds, 51 both the 1 H (δ 9.53 ppm) and 13 C (δ 169.4 ppm) NMR chemical shifts for the formate derivative are upfield of the corresponding values for the dithioformate complex (δ 11.84 ppm and δ 237.5 ppm, respectively).…”

“…51 Spectroscopically, [Tism Pr i Benz ]Cd(κ 1 -O 2 CH) and [Tism Pr i Benz ]Cd(κ 1 -S 2 CH) are characterized by signals at δ 9.53 ppm and δ 11.84 ppm in the 1 H NMR spectra, both of which exhibit satellites due to coupling to 111 Cd and 113 Cd nuclei, with the 3 J 111 Cd−H and 3 J 113 Cd−H coupling constants for the formate (84 and 88 Hz) being larger than the respective values for the dithioformate (80 and 84 Hz). As observed for other pairs of formate and dithioformate compounds, 51 both the 1 H (δ 9.53 ppm) and 13 C (δ 169.4 ppm) NMR chemical shifts for the formate derivative are upfield of the corresponding values for the dithioformate complex (δ 11.84 ppm and δ 237.5 ppm, respectively). As would be expected, ν as for the dithioformate moiety of [Tism Pr i Benz ]Cd(κ 1 -S 2 CH) (1006 cm −1 ) is significantly lower than that for the formate ligand of [Tism Pr i Benz ]Cd(κ 1 -O 2 CH) (1597 cm −1 ).…”

“…[κ 3 -Tism Pr i Benz ]­CdH also undergoes insertion of CS 2 into the Cd–H bond to afford the dithioformate counterpart, [Tism Pr i Benz ]­Cd­(κ 1 -S 2 CH) (Scheme ). The formation of [Tism Pr i Benz ]­Cd­(κ 1 -S 2 CH) is of particular note because dithioformate compounds of the main group metals are uncommon and there are no other examples of cadmium derivatives. As observed for the formate derivative, [Tism Pr i Benz ]­Cd­(κ 1 -O 2 CH), the dithioformate complex also exhibits unidentate coordination of the dithioformate ligand, which is noteworthy because the magnesium counterpart [Tism Pr i Benz ]­Mg­(κ 2 -S 2 CH) adopts a bidentate coordination mode …”