Control of Λ- and Δ-Isomerization of the Atrane Cages in Group XIV Metallatranes by Chiral Axial Substituents

The syntheses of the novel stannatranes N(CH₂CMe₂O)₃Sn-(1 S)-(-)-OC(O)C(OMe)(CF₃)(C₆H₅), 1( S, Δ), and N(CH₂CMe₂O)₃Sn-(1 R)-(+)-OC(O)C(OMe)(CF₃)(C₆H₅), 2( R, Λ), and germatranes N(CH₂CMe₂O)₃Ge-(1 S)-(-)-OC(O)C(OMe)(CF₃)(C₆H₅), 3( S, Δ), and N(CH₂CMe₂O)₃Ge-(1 R)-(+)-OC(O)C(OMe)(CF₃)(C₆H₅), 4( R, Λ) (with 1, S, Δ-configured/2, R, Λ-configured and 3, S, Δ-configured/4, R, Λ-configured being pairs of enantiomers) are reported. The compounds were characterized by NMR and IR spectroscopy, electrospray ionization mass spectrometry, and single crystal X-ray diffraction analysis. The epimerization via Λ ⇌ Δ ring flip of the enantiomeric stannatrane pair 1( S, Δ)/2( R, Λ) was investigated by NMR experiments at variable temperatures and density functional theory (DFT) calculations.

Ferrocene-based (photo)redox polymerization under long wavelengths

Ferrocene-based photoredox catalysis is proposed here for the first time.

Dipole-Bound Anions of Intramolecular Complexes

Dipole-bound molecular anions are often envisioned as unperturbed neutral, polar molecules with single excess electrons. We report the observation of intramolecular structural distortions within silatrane molecules due to the formation of their dipole-bound anions. The combination of Rydberg electron transfer-anion photoelectron spectroscopy (RET-PES) and ab initio computational methodologies (CCSD and MP2) was used to study 1-hydro- (HS) and 1-fluoro- (FS) silatranes and their dipole bound anions, HS^- and FS^-. The vertical detachment energies (VDEs) of HS^- and FS^- were measured to be 48 and 93 meV, respectively. Ab initio calculations accurately reproduced these VDE values as well as their photoelectron spectral profiles. This work revealed significant shortening (by ∼0.1 Å) of dative Si ← N bond lengths when HS and FS formed dipole-bound anions, HS^- and FS^-. Detailed computational (Franck-Condon) analyses explained the absence of vibrational features in the photoelectron spectra of HS^- and FS^-.

Delocalized Hypervalent Silyl Radical Supported by Amidinate and Imino Substituents

The reaction of the amidinato silylsilylene with a functionalized diaminochlorosilyl substituent, [LSiSi(Cl){(NtBu)₂C(H)Ph}] (1; L = PhC(NtBu)₂), with ArN═C═NAr (Ar = 2,6-iPr₂C₆H₃) in toluene afforded the delocalized hypervalent silyl radical [LSi^•(μ-CNAr)₂Si{(NtBu)₂C(H)Ph}] (2). It possesses a hypervalent silyl radical that delocalizes throughout the Si₂C₂ ring.

Prediction of hypervalent molecules: investigation on MnC (M = Li, Na, K, Rb and Cs; n = 1–8) clusters

The density of states (DOS) and electron localization function plots of the ground state Li₆C cluster.