Chalcogenolato complexes of bismuth and antimony. Syntheses, thermolysis reactions, and crystal structure of Sb(SC6H2Pri 3-2,4,6)3

Abstract

Antimony( 111) and bismuth (111) complexes of sterically demanding arenechalcogenolato ligands, M(EC,H,R',-2.4,6), (E = S or Se; M = Sb or Bi; R' = Me, Pri or But) have been prepared by either protolysis of the amides M [N(SiMe,),], with arenechalcogenols, or from MCI, by halide exchange (M = Bi or Sb). The complexes are monomeric in the solid state and sublime readily. The crystal structure of Sb( SC,H2Prl,-2,4,6), has been determined by X-ray diffraction. The compound possesses a trigonal-pyramidal geometry, with Sb-S distances of 2.41 8(2)-2.438(2) A and S-Sb-S angles of 94.69(7)-98.29(8)". Preliminary X-ray results on Bi(SeC6H2Pra,-2,4,6), showed that the compounds of Sb and Bi are isostructural. Thermolytic decomposition of some of the compounds has been carried out in the solid state. Compounds with R' = Me or Pri undergo reductive elimination to give elemental bismuth or antimony, whereas the bulky selenolates M (SeC6H,But,-2,4,6), afford M,Se,.

Covalently bonded compounds of heavy group 15/16 elements – Synthesis, structure and potential application in material sciences

“…In contrast, the use of tailor-made single-source precursors, in which the desired group 15 and group 16 elements are connected by a stable chemical bond and the material composition is ideally pre-formed on the molecular level, for the synthesis of nanostructured M 2 E 3 materials has only been recently demonstrated. [46,47,48,49,50] These studies clearly showed the strong influence of the organic substituents on the decomposition mechanism and formation of the desired material. For instance, Bochmann et al investigated the thermal decomposition of tris-selenolato-stibines and bismuthines of the type M(SeR) 3 .…”

“…9), [80] Bi(SePh) 3 , [81] and Bi(SeTrip) 3 . [46] M a n u s c r i p t Figure 9. Solid state structure of Sb(SeMe) 3 .…”

“…These interactions clearly exceed the sum of their covalent radii ∑ cov (M,Se) = 2.56 Å (M = Sb), 2.67 Å (M = Bi)), [59] but are less than the sum of their van der Waals radii (∑ vdW (M,Se) = 3.96 Å, M = Sb; 3.97 Å, M = Bi), [3] respectively. [81,46] M a n u s c r i p t Unfortunately, the crystal quality of Bi(SeTrip) 3 was too low to allow a detailed structure discussion. Bi(SePh) 3 crystallizes with two independent molecules in the asymmetric unit and forms a trigonal-pyramidal structure as was observed for Sb(SeMe) 3 [57] Ph 2 BiSePh (2.704(3) Å), [22] and Bi(SeR) 3 (R = 2-(4,4-dimethyloxazolino)phenyl, 2.6910(8), 2.7049(9), 2.7454(9) Å).…”

“…[46,47,48,49,50] insulators as well as thermoelectric materials. [142,143] Thermoelectric materials allow the interchange of thermal energy and electricity for the utilization of waste heat and for cooling.…”

“…While (2,4,6-t-Bu 3 C 6 H 2 Se) 3 Sb and (2,4,6-tBu 3 C 6 H 2 Se) 3 Bi were found to decompose at 200 °C with elimination of the selenane R 2 Se and subsequent formation of either Sb 2 Se 3 or a mixture of elemental bismuth and Bi 2 Se 3 , the analogous compounds (2,4,6-Me 3 C 6 H 2 Se) 3 Sb and (2,4,6-Me 3 C 6 H 2 Se) 3 Bi containing the sterically less demanding selenolato group decomposed with formation of elemental Sb and Bi as well as the diselenane R 2 Se 2 . [46] Despite several compounds of the types as-summarized in scheme 1 that have been mentioned as single source precursors for the formation of M 2 E 3 materials in the past, systematic studies on their use in material sciences including state-of-the-art characterization of the resulting materials have rather been recently performed. In the following, the promising potential of M a n u s c r i p t 41 several compounds of types I, III, IV and V for the synthesis of high-quality, nanoscalic M 2 E 3 materials via solution-based and gas phase-based routes will be summarized.…”