Synthesis and crystal structures of cyclodiazastannoxides fused cyclopentadienyl M–Sn (M = Mo, W) bonded organometallic heterocycle

Stannylene or Metallastanna(IV)ocane: A Matter of Formalism

“…[23] Further examples are found with compounds comprising a {TM À SnE 5 } pattern, with TM being a Group 6 element. [24] According to the isolobal concept, these TM centers appear less likely to act as lone-pair donors rather than being acceptors for a stannylene or stannyl lone pair. Although only a very limited number of examples for {TMÀ SnE 5 } and {TMÀSnE 4 } complexes were reported for electronrich TM centers, [5,6,18] the comparison of 1 and 2 has shown that even in complexes of the general type {TM À SnE 4 } (with pentacoordinate tin), the interpretation as a metallastanna-(IV)ocane-like compound might be appropriate.…”

Stannylen oder Metallastanna(IV)‐ocan – eine Sache des Formalismus

“…Nebengruppe. [24] Gemäß dem Isolobalkonzept scheinen diese ÜM-Zentren weniger als Elektronenpaardonoren, sondern vielmehr als Akzeptoren für ein Stannylen-oder Stannyl-Elektronenpaar zu fungieren. Obwohl nur eine sehr begrenzte Zahl an Beispielen für {ÜMSnE 5 } und {ÜMSnE 4 } mit elektronenreichem ÜM-Zentrum publiziert wurde, [5,6,18] hat der Vergleich von 1 und 2 gezeigt, dass selbst in Komplexen des allgemeinen Typs {ÜMSnE 4 } (mit pentakoordiniertem Zinnatom) die Auslegung als Metallastanna(IV)-ocan-artige Verbindung angebracht sein könnte.…”

New pentacoordinate bicyclodiazastannsulfide formed between the functionalized cyclopentadienyl ring and tin

“…Some key bond distances, such as M-Sn, Sn-N, Sn-O, Sn-S and Sn-Cl bond distances, are listed in Table 1. It can be seen that the W-Sn bond distance (2.7419(5) Å ) in 2 is shorter than those in bicyclodiazastannoxide analogues, [29], and l-{[C 5 H 4 (CH 3 )C@NA N@C(O)] 2 C 6 H 4 }{W(CO) 3 SnCl 2 (DMSO)} 2 (complex C, 2.8118(7) Å ) [29]. Furthermore, the Mo-Sn bond distances in complexes 3 and 5 are 2.7300(7) Å and 2.7365(3) Å , respectively, also shorter than that in corresponding bicyclodiazastannoxide analogues, such as {l- [28].…”

“…1-3, respectively. Although heteroatoms of the aryl groups in these three complexes do not coordinate to the tin atom of adjacent molecules, unlike in analogous bicyclodiazastannoxide fused cyclopentadienyl M-Sn bonded heterocycle [28,29], the tin atom in complexes 2, 3 and 5 is pentacoordinate, and has a distorted trigonal bipyramidal coordination with one chlorine atom and one nitrogen atom occupying the axial positions. The axial angle of \Cl-Sn-N is very analogous in these complexes (159.6(1)°for 2, 160.6(1)°for 3 and 160.66(5)°for 5, respectively).…”

“…The previous work of our group showed that the reaction of functionalized acetylcyclopentadienyl M-Sn bonded heterodimetallic complexes with phenylhydrazine formed a normal hydrazone, in which the tin atom is tetracoordinate, while their analogous reaction with aroylhydrazine yielded a novel bridging dinuclear bicyclodiazastannoxide [28,29], in which the tin atom, instead of assuming general pentacoordinate geometry in known bicyclodiazastannoxide analogues [30,31], prefers to be hexacoordinate through absorbing the chloridion or solvent molecules. It seems that it is difficult to obtain the pentacoordinate tin in these cyclopentadienyl M-Sn bonded heterocycles.…”