Communication: A complex with the cyclo‐R₂Sb₂S₂ [R = CH(SiMe₃)₂] ligand

Abstract

The reaction of the cyclo oligomers R nSb nS n [n = 2, 3; R = CH(SiMe3)2] with W(CO)5thf (thf = tetrahydrofuran) in thf results in trapping of the dimer in cyclo‐[R2Sb2S2][W(CO)5]2 (1). An X‐ray crystal structure analysis revealed that the complex contains a four‐membered antimony–sulfur ring in an almost planar conformation, where the alkyl groups occupy cis positions and the W(CO)5 units are bonded trans to the alkyl groups on the antimony atoms. Copyright © 2002 John Wiley & Sons, Ltd.

Syntheses and chemistry of hypervalent cyclo-R4Sb4, cyclo-(RSbE)n[R = 2-(Me2NCH2)C6H4, E = O, S] and precursors

“…The central four-membered Sb 2 S 2 ring is planar (Fig. 5), with a transanular Sb 20 The product isolated in the syntheses of compound 4 indicates that the dimeric form of this monoorganoantimony(III) sulfide is energetically favoured in comparison to the corresponding monomeric species.…”

“…17 The preparation of the trimers (RSbSe) 3 [R = 2,4,6-[(Me 3 Si) 2 CH] 3 C 6 H 2 , 16 2,6-[(Me 3 Si) 2 CH] 2 -4-[(Me 3 Si) 3 C]C 6 H 2 18 ] and the presence of both dimers and trimers in the solution of [(Me 3 Si) 2 CHSbE] n (E = S, Se Te) 19 were also reported. However, the dimers [(Me 3 Si) 2 CHSbE] 2 (E = S, 20 Se 21 ) could be stabilized only as (RSbE) 2 [W(CO) 5 ] 2 complexes in which the antimony atoms are coordinated to metal carbonyl fragments.…”

“…Fig. 6 The 1 H NMR spectrum of 4 in CDCl 3 : (a) aliphatic region, and (b) aromatic region [() isomer 4a, and () isomer 4b].It was previously reported that the reaction between the ring-ring equilibrium mixture of cyclo-[(Me 3 Si) 2 CHSbS] n (n = 2, 3) and W(CO) 5 (THF) afforded almost quantitatively the selective formation of the cyclo-[(Me 3 Si) 2 CHSbS] 2 [W(CO) 5 ] 2 complex; it contains metal carbonyl units coordinated to the Sb atoms in cis positions relative to a Sb 2 S 2 ring and trans positions with respect to the alkyl groups 20. The reaction between the heterocyclic compound 4 and W(CO) 5 (THF) in a 1 : 2 molar ratio was performed in order to investigate the effect of the 2-(Me 2 NCH 2 )C 6 H 4 groups.…”

Synthesis, Structure, and Reactivity of Intramolecularly Coordinated Organoantimony and Organobismuth Sulfides

“…Although some molecular structures of dimeric monoorganoantimony sulfides [RSbS] 2 have been determined, to the best of our knowledge, all of them can be described as trans type with the substituent R located mutually on the opposite sides of the central ring. The cis position was in some compounds caused by coordination of the antimony or the sulfur atom to a transition metal. , The molecular structure of cis - 6 is depicted in Figure and represents the first example of a “free” cis isomer of monorganoantimony sulfide characterized by X-ray diffraction in the solid state. The cis position of both ligands L 2 in 6 resulted in significant puckering of the central Sb 2 S 2 ring (see Figure ).…”

Low-Valent Organoantimony and -bismuth Compounds with Neopentyl and (Trimethylsilyl)methyl Substituents

“…The dibismuth chalcogenides (R 2 Bi) 2 E (E ) S, Te; R ) (Me 3 Si) 2 CH) are formed in 88% (E ) S) or 53% (E ) Te) yield from R 2 BiCl with Na 2 S in water or with Na 2 Te in liquid ammonia. 24 Both compounds are unstable at room temperature. They decompose with formation of R 3 Bi and bismuth chalcogenides (Scheme 9).…”