New Routes to Heterocyclic Selenium Sulfides.

Selenium Imides: 77Se NMR Investigations of the SeCl2−tBuNH2 Reaction and X-ray Structures of Se3(NtBu)3, tBuNSe(μ-NtBu)2SO2, and tBuNSe(μ-NtBu)2SeO

“…The assignment of these resonances to Se Se N and Se Se Se environments, respectively, is consistent with the observed intensities. Furthermore, the value of δ 518 is in the range expected for a selenium atom attached to two selenium neighbors by analogy with the known 77 Se NMR chemical shifts for cyclic selenium sulfides. , By contrast, Wrackmeyer et al reported 77 Se NMR chemical shifts of 1391.0 and 1163.6 ppm for 1 for CH 2 Cl 2 …”

Syntheses of THF Solutions of SeX2 (X = Cl, Br) and a New Route to Selenium Sulfides SenS8-n (n = 1−5): X-ray Crystal Structures of SeCl2(tht)2 and SeCl2·tmtu

“…The application of this procedure to Ph 3 PS provides a mild route to eight-membered selenium sulfide rings Se n S 8 - n ( n = 1−5), which were identified by 77 Se NMR spectroscopy (Figure ). The assignments were made on the basis of previous data for the composition of sulfur−selenium melts containing 77 Se-enriched samples, which were investigated for melt compositions ranging from 10 to 40 mol % Se. 12b,− There is remarkably good agreement between the 77 Se NMR chemical shifts found for the selenium sulfide rings produced from the reaction SeCl 2 and Ph 3 PS and those reported for the corresponding rings in sulfur−selenium melts. The assignments are shown in Figure , and the relative abundances of selenium sulfides produced by the two different routes are compared in Table .…”

“…lit. δ( 77 Se) 615 in CS 2 ) . Removal of the solvent from the filtrate gave colorless crystals consisting of Ph 3 PCl 2 as the major product with minor amounts of Ph 3 PO.…”

Titanocene Selenide Sulfides Revisited: Formation, Stabilities, and NMR Spectroscopic Properties

“…This information was utilized in the preliminary identification of individual molecular components in the mixtures of titanocene selenide sulfides [TiCp 2 Se x S 5− x ] [15]. The assignment of the 77 Se NMR spectra of mixtures containing different initial molar ratios of sulfur and selenium was based on the consideration of the spectroscopic data of [TiCp 2 Se 5 ] [25], on the constant intensities between some resonances, as the Se:S ratio is varied, and on the trends in the 77 Se chemical shifts [28,29,30]. This semi-quantitative analysis has then been utilized in resolving the disorder in the chalcogen atom positions in the crystalline [TiCp 2 Se x S 5− x ] phase, which was prepared using the initial Se:S molar ratio of 3:2 [15].…”