Reactivity of Bis(sulfonyl) O,C,O‐Chelated Metallylenes in Cycloaddition with ortho‐Benzoquinone: An Experimental and Computational Study

Abstract

The reactivity of a germylene and a stannylene containing an O,C,O‐coordinating pincer‐type ligand [2,6‐(RO2S)2‐4‐tBuC6H2]– (R = tolyl) was investigated towards ortho‐benzoquinone. The effect of the bis(sulfonyl) O2S‐C‐SO2 pincer‐type ligand and the benzoquinone group on the stability of the resulting cycloadducts was studied through experimental and computational techniques. The structures of the obtained products were determined in solution and in the solid state by multinuclear NMR and IR spectroscopy, mass spectrometry and single‐crystal X‐ray diffraction. DFT calculations, carried out at the B3LYP‐D3/Def2‐TZVP and M11‐L/Def2‐TZVP levels of theory, were performed in order to bring further clarification concerning the nature of the chemical bonding and the coordination geometry of these species. In addition, the stability of the metallylenes towards hydrolysis and dimerization was assessed.

Recent Advances and Prospects in the Chemistry of o‐Benzoquinones

“…Cycloaddition reaction of o‐ benzoquinone with bis‐sulfonyl ligands having O, C, O coordination was also reported by Deak et.al . Here, the reactivity was analyzed from the stability of the cycloadduct both computationally and experimentally.…”

New phosphorus containing bis-sulfone ligands

“…Based on the good results obtained with the bis-sulfone 1 in the stabilization of low valent group 14 elements and their reactivity, [18,19] the synthesis of phosphorus containing derivatives was also realised. A new dichlorophosphine was obtained with bis-sulfone 1, as shown in Scheme 1, using a slightly modified method from literature.…”

“…[20,25] The tolyl groups are situated on opposite sides of the central aromatic ring; the S=O bonds are close to values observed in the case of the previously reported metallylenes with bis-sulfone ligands. [17][18][19] The O1-P1 distance in the dichlorophosphine 2 is of 2.754(3) Å, value between the sum of the covalent radii (1.73 Å) [26] and the sum of the van der Waals radii (3.38 Å), [27,28] while the O3-P1 distance of 3.367(3) Å is almost equal to the sum of the van der Waals radii (3.38 Å). [27,28] The orientation of the sulfonyl groups (the O1, O3) and the phosphorus atom does not make possible an interaction, moreover, in the case of the phosphorus(III) atom, the presence of the lone pair of electron could lead to repulsions with the lone pair of electron on the oxygen atom.…”

“…The importance of bissulfone as ligands was recently highlighted as they function as pincer-type ligands for the stabilization of metallylenes and have an important effect in their reactivity. [17][18][19] …”

Palladium and Ruthenium Derivatives Stabilised by bis-Sulfone Ligand

“…Recently, we highlighted the utility of the bis-sulfone ligand 1,3-bis{(4methylphenyl)sulfonyl}-5-tert-butylbenzene, containing two sulfonyl groups, as a pincer ligand for the stabilization of metallylenes and their transition metal compounds and cycloadducts. [32,33] In order to evaluate the properties and stability of organometallic derivatives containing a heavy p-block element or transition metal, additionally the effect induced by a ligand containing sulfonyl groups was studied. It's worth mentioning that in the literature there are several examples for transition metal containing derivatives stabilized by sulphur based, sulfonyl or sulfinyl containing ligands, where the transition metal is bonded either through the coordination of the sulphur or the oxygen atom, [16,[34][35][36][37] however, there are only a few examples for such compounds containing a bis-sulfonyl ligand.…”