η³‐Allyl Coordination at Tin(II)—Reactivity towards Alkynes and Benzonitrile

Abstract

We herein report the synthesis and characterization of a terphenyl-substituted Sn(II) allyl compound featuring an η(3) coordination mode in solution and in the solid state. Two examples for the interesting reactivity of the allyl Sn(II) molecule are presented: Reactions with terminal alkynes result in the formation of tricyclic compounds by CC bond formation and the dimerization of two Sn moieties whereas the reaction with benzonitrile leads to a sixteen-membered ring system through CH activation.

(η4-Butadiene)Sn(0) Complexes: A New Approach for Zero-Valent p-Block Elements Utilizing a Butadiene as a 4π-Electron Donor

“…The Sn−C α and Sn−C β bond lengths are 2.300(5)−2.341(5) and 2.419(6)−2.451(4) Å, respectively, making them 5−12% longer than the original Sn−C α bonds in 1 (approximately 2.19 Å). Such long Sn−C bonds were also found in [(Ar′Sn) 2 (μ 2 -η 2 :η 3 -cot)] (2.364−2.590 Å), 19 the stannapyramidane Sn[η 4 -C 4 (SiMe 3 ) 4 ] (2.339−2.343 Å), 20 and (η 3 -allyl)Sn(II) complexes (2.380−2.418 Å), 21 implying that the Sn−C bonds in 2 and 3 are considered π-bonds rather than σ-bonds. Thus, they can be regarded as (η 4 -butadiene)Sn(0) complexes.…”

A nitrogen-base catalyzed generation of organotin(ii) hydride from an organotin trihydride under reductive dihydrogen elimination

“… 65 The related η 3 -coordinated allyl complex Ar*Sn–allyl was reported only recently. 66 In solution the Cp* moiety reveals only one resonance in 1 H NMR spectroscopy, indicating dynamic exchange on the NMR time scale. 119 Sn NMR resonance is found at δ = –25 ppm which is well in accord with the literature for a half-sandwich complex.…”

Tetrylones: An Intriguing Class of Monoatomic Zero‐valent Group 14 Compounds

“…In the crystalline state, the pyramidal coordination environment fort he tin atom in 27 (Figure 22), demonstrates ad rastic deviation from the C 4 plane of the butadiene moiety,a nd suggests interactions with C a and C b .T he SnÀC a and SnÀC b bond lengths of 2.314(4) and 2.451(4) ,r espectively,a re longert han the SnÀC a bonds in 26 ( % 2.19 ). Such long SnÀCb onds were also found in the stannapyramidaneS n[h 4 -C 4 (SiMe 3 ) 4 ]( 2.339-2.343 ) [30] and (h 3 -allyl)Sn II complexes (2.380-2.418 ), [31] which indicates that the SnÀCb onds in 27 should be considered as p-bonds rather than s-bonds. Therefore, 27 can be interpreted as a( h 4 -butadiene)Sn(0) complex.…”

“…The Sn−C α and Sn−C β bond lengths of 2.314(4) and 2.451(4) Å, respectively, are longer than the Sn−C α bonds in 26 (≈2.19 Å). Such long Sn−C bonds were also found in the stannapyramidane Sn[ η 4 ‐C 4 (SiMe 3 ) 4 ] (2.339–2.343 Å) and ( η 3 ‐allyl)Sn II complexes (2.380–2.418 Å), which indicates that the Sn−C bonds in 27 should be considered as π‐bonds rather than σ‐bonds. Therefore, 27 can be interpreted as a ( η 4 ‐butadiene)Sn(0) complex .…”