New Polydentate Trimethylsilyl Chalcogenide Reagents for the Assembly of Polyferrocenyl Architectures

Abstract

A series of polychalcogenotrimethylsilane complexes Ar(CH2ESiMe3)n, (Ar = aryl; E = S, Se; n = 2, 3, and 4) can be prepared from the corresponding polyorganobromide and M[ESiMe3] (M = Na, Li). These represent the first examples of the incorporation of such a large number of reactive -ESiMe3 moieties onto an organic molecular framework. They are shown to be convenient reagents for the preparation of the polyferrocenylseleno- and thioesters from ferrocenoyl chloride. The synthesis, structures, and spectroscopic properties of the new silyl chalcogen complexes 1,4-(Me3SiECH2)2(C6Me4) (E = S, 1; E = Se, 2), 1,3,5-(Me3SiECH2)3(C6Me3) (E = S, 3; E = Se, 4) and 1,2,4,5-(Me3SiECH2)4(C6H2) (E = S, 5; E = Se, 6) and the polyferrocenyl chalcogenoesters [1,4-{FcC(O)ECH2}2(C6Me4)] (E = S, 7; E = Se, 8), [1,3,5-{FcC(O)ECH2}3(C6Me3)] (E = S, 9; E = Se, 10) and [1,2,4,5-{FcC(O)ECH2}4(C6H2)] (E = S, 11 illustrated; E = Se, 12) are reported. The new polysilylated reagents and polyferrocenyl chalcogenoesters have been characterized by multinuclear NMR spectroscopy ((1)H, (13)C, (77)Se), electrospray ionization mass spectrometry and, for complexes 1, 2, 3, 4, 7, 8, and 11, single-crystal X-ray diffraction. The cyclic voltammograms of complexes 7-11 are presented.

Polydentate chalcogen reagents for the facile preparation of Pd2 and Pd4 complexes

“…17 1,2-Bis((trimethylsilylchalcogeno)methyl)benzene 1a and 1b are readily prepared in good yield from the reaction of 1,2-bis-(bromomethyl)benzene with lithio(trimethylsilyl)-chalcogenolate (Scheme 2), further expanding on the reported synthesis of 1,4-, 1,3,5-and 1,2,4,5-polychalcogenosilanes Ar(CH 2 ESi-Me 3 ) n (n = 2, 3, 4) from the corresponding polybromomethylbenzene and alkali metal (trimethylsilyl) chalcogenolate M[ESiMe 3 ] (M = Na, Li) under mild conditions. 21 The portionwise addition of organobromine reagent to the solution of Li[ESiMe 3 ] in Et 2 O at room temperature, followed by stirring for twelve hours, yielded 1,2-(Me 3 SiSCH 2 ) 2 (C 6 H 4 ) (84%) 1a and 1,2-(Me 3 SiSeCH 2 ) 2 (C 6 H 4 ) (71%) 1b as a colourless and pale yellow oily solids, respectively, upon extraction with pentane. They decompose readily in the presence of air; however, they are stable for several days at room temperature under an inert atmosphere.…”

“…These results match well with previously reported data for 1,2,4,5-(Me 3 SiECH 2 ) 4 (C 6 H 2 ) (E = S, Se). 21 Treatment of cis-[MCl 2 L 2 ] (M = Ni, Pt, Pd; L = mono-or 1/2bidentate phosphine ligand) with organochalcogenides RE − readily gives mononuclear cis-[M(ER) 2 L 2 ] (E = S, Se, Te), and the complexes have proven to be important precursors for the stepwise synthesis of dinuclear complexes. Thus, the reaction of another cis-[MCl 2 L 2 ], activated in the presence of a cation, with cis-[M(ER) 2 L 2 ] gives a homo-binuclear complex [M 2 (ER) 2 L 2 ]X 2 .…”

“…Chemicals were used as received from Sigma-Aldrich. [PdCl 2 (dppp)], 30 1,2-bis(bromomethyl)benzene, 31 1,2,4,5-(Me 3 SiSCH 2 ) 4 C 6 H 2 21 and Li[ESiMe 3 ] 32 (E = S, Se) were synthesized according to literature procedures. High-resolution mass spectral measurements (1a and 1b) were performed on Finningan MAT 8400 using electron impact (EI) ionization.…”

Tethered Polynuclear Copper–Chalcogenolate Assemblies Enabled via NHC Ligation

“…With continued interest in the assembly of molecules containing −ESiMe 3 groups, we reported the synthesis and the characterization of a series of polychalcogenotrimethylsilanes Ar(CH 2 ESiMe 3 ) n (Ar = aryl; E = S, Se; n = 2 (ortho, para), 3, and 4). 5 These molecules represent the first examples of the incorporation of such a large number of reactive −ESiMe 3 moieties onto an organic molecular scaffold. We also demonstrated the reactivity of −ESiMe 3 toward ferrocenoyl chloride as a simple route for the formation of polyferrocenylchalcogenoesters 5 and the preparation of butterfly-shaped Pd 2 E 2 (E = S, Se) complexes via the reaction of [(dppp)PdCl 2 ] (1,3-bis(diphenylphosphino)propane)palladium(II)) with the disubstituted thio-and selenotrimethylsilane reagents, 1,2-(Me 3 SiECH 2 ) 2 (C 6 H 4 ).…”

The Syntheses and Crystal Structures of the First Disiloxane‐1,3‐dithiol and Its Cadmium Complex

“…[25,26] Silanediols were also employed in organocatalysis [27] and they were studied as sensitizers for solar cells in 2013. However, silicon chalcogenides have been applied as reagents in organic syntheses, [30,31] and metal complexes with silyl chalcogenolate ligands have been used as precursors of metal chalcogenide nanoparticles. [29] Heavier analogs of molecular silicon-oxygen compounds bearing silicon-sulfur functionalities are usually treated as synthetic challenges and chemical peculiarities.…”