Synthesis and Structural Characterization of Magnesium‐Substituted Polystibides [(LMg)₄Sb₈]

Abstract

Redoxr eactions of [(L 1,2 Mg) 2 ]a nd Sb 2 R 4 (R = Me, Et) yielded the first Mg-substituted realgar-type Sb 8 polystibides [(L 1,2 Mg) 4 (m 4 ,h 2:2:2:2 -Sb 8 )] (L 1 = HC[C(Me)N(2,4,6-Me 3 C 6 H 2 )] 2 ,L 2 = HC[C(Me)N(2,6-i-Pr 2 C 6 H 3 )] 2 ). Compounds [(L 1,2 Mg) 2 ]s erve both as reducing agents,i nitiating the cleavage of the Sb À Cbonds,and as stabilizers for the resulting Sb 8 polyanion. The polystibides were characterized by NMR and IR spectroscopies,elemental analysis,and X-ray structure analysis.I na ddition, results from quantum chemical calculations are presented. Novosibirsk (Russian Federation) Supportinginformation for this article (including experimental details, 1 Hand 13 CNMR and IR spectra, and computational details) can be found under http://dx.Science Foundation for financial support . TheS iberian Supercomputer Center is gratefully acknowledged for providing computational resources.Keywords: cluster compounds ·m ain group elements ·m etalmetal interactions ·subvalent compounds

Samarium Polystibides Derived from Highly Activated Nanoscale Antimony

“…In 2016, Schulz et al. reported on the synthesis of Mg‐substituted realgar‐type polystibides [(L 1, 2 Mg) 4 ( μ 4 , η 2:2:2:2 ‐Sb 8 )] (L 1 =HC[C(Me)N(2,4,6‐Me 3 C 6 H 2 )] 2 , L 2 =HC[C(Me)N(2,6‐i‐Pr 2 C 6 H 3 )] 2 ), which arose from the cleavage of Sb 2 R 4 (R=Me, Et) using Mg I reductants . It has not been reported that similar compounds are accessible using elemental Sb itself.…”

“…[12] It has not been reported that similar compounds are accessible using elemental Sb itself.T hus,w ef elt challenged to investigate whether f-element polystibides could be obtained from such areadily available source. [12] It has not been reported that similar compounds are accessible using elemental Sb itself.T hus,w ef elt challenged to investigate whether f-element polystibides could be obtained from such areadily available source.…”

“…(L 1 = HC[C(Me)N(2,4,6-Me 3 C 6 H 2 )] 2 ,L 2 = HC[C(Me)N(2,6-i-Pr 2 C 6 H 3 )] 2 ), which arose from the cleavage of Sb 2 R 4 (R = Me,E t) using Mg I reductants. [12] It has not been reported that similar compounds are accessible using elemental Sb itself.T hus,w ef elt challenged to investigate whether f-element polystibides could be obtained from such areadily available source.…”

“…Whilst the bonding situation of the analogous Mg structure has been elucidated very recently, [12] we focused on the synthetic usability of elemental antimony in reduction chemistry.One major drawback of using Sb/Hg alloys turned out to be the coexistence of different Sm/Sb species in the reaction mixture,w hich could not be completely separated from each other. Although tuning the reaction conditions allowed some control over product formation, the presence of Sm/Sb/Hg species could not be excluded.…”

Reduction of [Cp*Sb]4with Subvalent Main‐Group Metal Reductants: Syntheses and Structures of [(L1Mg)4(Sb4)] and [(L2Ga)2(Sb4)] Containing Edge‐Missing Sb4Units

“…[10e,f] We recently showed that the reaction of Sb(NMe2)3 with L 2 Ga yielded the distibene L 2 Ga(Me2N)Sb=SbGa(Me2N)L 2 , which upon heating gave [{L 2 (Me2N)Ga}2Sb4], the first Sb analogue of bicyclo[1,1,0]butane formally containing a [Sb4] 2dianion. [11] In addition, the reaction of distibines R4Sb2 (R = Me, Et) containing divalent Sb atoms with [L 2,3 Mg]2 yielded the Zintl-type ions [(L 2,3 Mg)4(4, 2:2:2:2 -Sb8)] {L 3 = HC[C(Me)N(2,4,6-Me3C6H2)]2}, [12] while the analogous reaction with L 2 M (M = Al, Ga) proceeded with insertion of L 2 M into the Sb-Sb bond and subsequent formation of L 2 M(SbEt2)2. [13] We now focused on reduction reactions of cyclo-tetrastibine [Cp*Sb]4, which formally contains monovalent Sb atoms, and report herein on the synthesis of…”