Cyclic Four‐Membered Stanna Thio and Seleno Compounds from 2‐Aminopyridinato Stannylenes

Abstract

In this paper, we have used 2-aminopyridinato ligands (1 and 2) to stabilize two four-coordinated tin(II) aminopyridinato compounds ([Sn{NPh(py)} 2 ] (3) and [Sn{N(SiMe 3 )py} 2 ] (4)) (py=pyridine) through a salt elimination reaction. The reactions of 3 and 4 with elemental sulfur and selenium resulted in the formation of compounds (5-8) with Sn 2 E 2 (E = S and Se)

Distannabarrelenes with Three Coordinated SnII Atoms

“…[26,29] The SnÀSe bond length (2.388(5) )i n5-Ph is in line with the literature known values for Sn=Se double bonds (2.37-2.42 )i ns tannaneselones, [26,30] but smallert han the SnÀ Se single bond length (2.55-2.60 ). [26,29] In 4-Ph and 5-Ph,t he Sn II ÀC ADC bond lengths( 2.26-2.28 )a re similar to those of 3-Ph (2.24 to 2.27 ), whereas the Sn IV ÀC ADC bond lengths( 2.18-2.20 )a re slightly shorter than those of 3-Ph (Table 1). This bond length trend for Sn II and Sn IV units is expected, whichi s also in line with the Jurkschat's Sn IV compounds (2.13-2.15 ) featuring aC 4-bound aNHC.…”

Four‐Coordinate Germylene and Stannylene and their Reactivity towards Se & Te**

“…5 also crystallizes in a triclinic P‐1 space group and displays a distorted square pyramidal geometry at the tin(II) centre. The bond distances Sn1‐N1 and Sn1‐N2 in 5 are 2.540(8) Å and 2.593(7) Å, respectively, which are slightly longer than the previously reported N→Sn bonds in [Sn{NPh(py)} 2 ] and [Sn{N(SiMe 3 )py} 2 ] ( 2.368–2.416 Å) [17] …”

“…The bond distances Sn1-N1 and Sn1-N2 in 5 are 2.540(8) Å and 2.593(7) Å, respectively, which are slightly longer than the previously reported N!Sn bonds in [Sn{NPh(py)} 2 ] and [Sn{N(SiMe 3 )py} 2 ] ( 2.368-2.416 Å). [17] Further, we were interested in generating a Ge(II) cation from 2; Hence we treated 2 with AlCl 3 , which is a well-known Lewis acid for the abstraction of the Cl atom. [18] However, we isolated an oxidized product 6 (Scheme 1), where Ge(II) centre is oxidized to Ge(IV).…”

Stannylenes and Germylenes Stabilized by Tetradentate Bis(amidine) Ligands with a Rigid Naphthalene Backbone

“…In the 13 C NMR spectrum, the characteristic signal of the NCN fragment appears at 167.4 ppm. In the 119 Sn NMR spectrum, a very high field chemical shift at −648.0 ppm is observed, a resonance signal that is more high-field shifted than those of previously reported Sn 2 S 2 -bridged dimeric complexes [ 26 , 27 ].…”