Search results for "selenium"
showing 10 items of 178 documents
CCDC 145362: Experimental Crystal Structure Determination
2000
Related Article: T.Maaninen, T.Chivers, R.Laitinen, E.Wegelius|2000|Chem.Commun.||759|doi:10.1039/b001002m
CCDC 1429063: Experimental Crystal Structure Determination
2017
Related Article: Thomas Quell, Michael Mirion, Dieter Schollmeyer, Katrin M. Dyballa, Robert Franke, Siegfried R. Waldvogel|2016|ChemistryOpen|5|115|doi:10.1002/open.201500206
CCDC 244552: Experimental Crystal Structure Determination
2005
Related Article: T.Maaninen, H.M.Tuononen, K.Kosunen, R.Oilunkaniemi, J.Hiitola, R.Laitinen, T.Chivers|2004|Z.Anorg.Allg.Chem.|630|1947|doi:10.1002/zaac.200400286
CCDC 156128: Experimental Crystal Structure Determination
2001
Related Article: T.Maaninen, T.Chivers, R.Laitinen, G.Schatte, M.Nissinen|2000|Inorg.Chem.|39|5341|doi:10.1021/ic000598b
CCDC 156127: Experimental Crystal Structure Determination
2001
Related Article: T.Maaninen, T.Chivers, R.Laitinen, G.Schatte, M.Nissinen|2000|Inorg.Chem.|39|5341|doi:10.1021/ic000598b
CCDC 145363: Experimental Crystal Structure Determination
2000
Related Article: T.Maaninen, T.Chivers, R.Laitinen, E.Wegelius|2000|Chem.Commun.||759|doi:10.1039/b001002m
Selenium affects biosilica formation in the demosponge Suberites domuncula
2005
Selenium is a trace element found in freshwater and the marine environment. We show that it plays a major role in spicule formation in the demosponge Suberites domuncula. If added to primmorphs, an in vitro sponge cell culture system, it stimulates the formation of siliceous spicules. Using differential display of transcripts, we demonstrate that, after a 72-h exposure of primmorphs to selenium, two genes are up-regulated; one codes for selenoprotein M and the other for a novel spicule-associated protein. The deduced protein sequence of selenoprotein M (14 kDa) shows characteristic features of metazoan selenoproteins. The spicule-associated protein (26 kDa) comprises six characteristic repe…
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
2000
The reaction of SeCl2 with tert-butylamine in various molar ratios in THF at −78 °C has been investigated by 77Se NMR spectroscopy. In addition to the known Se−N heterocycles Se6(NtBu)2 (1) and Se9(NtBu)6 (2), the acyclic imidoselenium(II) dichlorides ClSe[N(tBu)Se]nCl (4, n = 1; 5, n = 2) and two new cyclic selenium imides [Se3(NtBu)2]n (3, n = 1 or 2) and Se3(NtBu)3 (6) have been isolated and identified. An X-ray analysis shows that 6 is a six-membered ring in a chair conformation with |d(Se−N)| = 1.833 A. Crystal data: 6, trigonal, P3c1, a = 9.8660(3) A, c = 20.8427(7) A, V = 1757.0(1) A3, Z = 6. The 1H, 13C, and 77Se NMR data for 1−6 are reported, and some reassignments of earlier lite…
Composés métallocèniques chalcogènés. Action des dihydrures de zirconocène et de hafnocène sur le soufre, le sélénium et le tellure
1989
Resume Dimeric zirconocene and hafnocene dihydrides [(η 5 -RC 5 H 4 ) 2 M(H)(μ-H)] 2 (M = Zr, Hf) react with grey selenium or tellurium to afford the known four-membered bimetallacyclic compounds [(η 5 -RC 5 H 4 ) 2 M(μ-E)] 2 (E = Se, Te) as the sole organometallic products. In the case of sulfur the first step of the reaction is shown to involve the insertion of a chalcogen atom into the metal-hydrogen bonds to give the bis-hydrogenosulfide (η 5 -t-BuC 5 H 4 ) 2 M(SH) 2 (M = Zr, Hf), which reacts either with the starting dihydride to give [(η 5 -t-BuC 5 H 4 ) 2 M(μ-S)] 2 or with the unchanged sulfur to afford the metallacyclohexasulfane (η 5 -t-BuC 5 H 4 ) 2 MS 5 and hydrogen sulfide. Thes…