The bonding situation in triethylchalcogenostiboranes – polarized single bonds vs. double bonds

The bonding situation in triethylchalcogenostiboranes - polarized single bonds vs. double bonds.

Triethylchalcogenostiboranes Et3Sb[double bond, length as m-dash]E (E = S , Se ) were synthesized and their solid state structures were determined. The Sb-Se bond length is the shortest ever reported. Short SbE contacts were not observed. According to quantum chemical calculations, the bonding situation in and is best described as a polarized Sb-E single bond.

Dynamic 1H NMR Study Around the Carbon–Carbon Double Bonds and Carbon–Carbon Single Bonds in a Particular Phosphorous Ylide and 2,5-Dihydro-5,5-Diaryl-2-Thio-1H-Imidazoles

Stable crystalline phosphorus ylides are obtained in excellent yields from the 1:1:1 addition reactionbetween hydantoins or thiohydantoins and dialkyl acetylenedicarboxylates in the presence oftriphenylphosphine. These phosphoranes undergo smooth intramolecular Wittig reaction followedby an electrocyclic ring opening to produce dialkyl (E)-2-(2,5-dihydro-5,5-diaryl-2-thioxo-1H-imidazol-4-yl)fum...

Single Molecular Bonds

■ Abstract On laboratory time scales, the energy landscape of a weak bond along a dissociation pathway is fully explored through Brownian-thermal excitations, and energy barriers become encoded in a dissociation time that varies with applied force. Probed with ramps of force over an enormous range of rates (force/time), this kinetic profile is transformed into a dynamic spectrum of bond rupture...

Ultrathin carbon nanotube with single, double, and triple bonds.

A metastable carbon nanotube with single, double, and triple bonds has been predicted from ab initio simulation. It results from the relaxation of an ideal carbon nanotube with chirality (2,1), without any potential barrier between the ideal nanotube and the new structure. Ten-membered carbon rings are formed by breaking carbon bonds between adjacent hexagons; eight-membered rings, already pres...

Sukuk Vs Conventional Bonds A study into the performance of Islamic Bonds