Facile insertion of ethylene into a group 14 element-carbon bond: effects of the HOMO–LUMO energy gap on reactivity

Abstract

The diarylstannylenes, Sn(AriPr4)2 and Sn(AriPr6)2, (AriPr4 = C6H3-2,6-(C6H3-2,6-iPr2)2, AriPr6 = C6H3-2,6-(C6H2-2,4,6-iPr3)2), undergo a facile migratory insertion reaction with ethylene at 60 °C to afford the alkyl aryl stannylenes AriPr4SnCH2CH2AriPr4 and AriPr6SnCH2CH2AriPr6 which were characterized via1H, 13C and 119Sn NMR, UV-vis and IR spectroscopy, as well as by X-ray crystallography.

Carbon monoxide insertion at a heavy p-block element: unprecedented formation of a cationic bismuth carbamoyl

“…Despite these challenges, considerable efforts in designing heavy main group species that undergo well-defined reactions with small molecules have been crowned with success. The distannyne Sn 2 Aryl 2 has been shown to reversibly add two equivalents of ethylene across its SnSn bond to give the corresponding distannane (Scheme 1a, Aryl = C 6 H 3 -2,6(C 6 H 3 -2,6-iPr 2 ) 2 ) 6,7. This distannyne and closely related derivatives also react with dihydrogen to give a dinuclear tin species with two bridging hydride ligands, a reaction that has recently been shown to be reversible (Scheme 1b).…”

Reversible Activation and Transfer of White Phosphorus by Silyl‐Stannylene

“…The ∡ C1‐Sn1‐Si1 bond angle in 2 is 113.50(14)° and falls within the range of aryl substituted two‐coordinate Sn II complexes (96.9–117.6°) [12] . Notably, two‐coordinate stannylenes [R 2 Sn] with broad bond angles (∡ R‐Sn‐ R =112 to 118°) have been shown to activate a wide range of small molecules [8c–e] …”

“…Compound 2 was isolated in 80 % yield as a dark blue solid (Scheme 1 b) and is soluble in polar solvents such as tetrahydrofuran, but poorly soluble in nonpolar organic solvents such as benzene or toluene. The 119 Sn{ 1 H} NMR spectrum of compound 2 showed a characteristic signal for the tin center at δ 197 ppm, which is significantly upfield in comparison to 1 (562 ppm) and the bis(aryl)stannylene ( Mes Ter) 2 Sn (1971 ppm) [8e, 10] . This indicates an electron rich Sn II center, which can be attributed to the substituent effect (Si t Bu 3 vs. Mes Ter).…”

Synthesis, characterization, DFT, and TD-DFT studies of (E)-5-((4,6-dichloro-1,3,5-triazin-2-yl)amino)-4-hydroxy-3-(phenyldiazenyl)naphthalene-2,7-diylbis(hydrogen sulfite)

“…From Fig. 4, Eg is 2.95 eV, which is relatively low [27][28][29][30][31][32], hence excitation from the HOMO to LUMO is easily feasible; this is a basic property of a reactive molecule. Also, the energy gap between HOMO-1 and LUMO + 1 orbitals was determined for a more explicit information about the studied molecule; we obtained Eg to be 4.94 eV.…”