Multiple bonding, π-bonding contributions and aromatic character in isoelectronic boron-phosphorus, boron-arsenic, aluminum-nitrogen and zinc-sulfur compounds

Abstract

Abstract

Triple-Bonded Boron≡Phosphorus Molecule: Is That Possible?

“…From Table , the DFT computations anticipate that the BP triple bond lengths (Å) are between 1.713 and 1.777 (M06-2X/Def2-TZVP), 1.714 and 1.781 (B3PW91/Def2-TZVP), and 1.725 and 1.793 (B3LYP/LANL2DZ+dp). According to the available experimental data, the bond distances (Å) for the B–P single bond and the BP double bond are 1.94–2.0 and 1.786–1.859, − , respectively. The bond lengths of the BP triple bonds that are obtained from DFT calculations are shorter than those that are acquired experimentally. − , …”

“…According to the available experimental data, the bond distances (Å) for the B–P single bond and the BP double bond are 1.94–2.0 and 1.786–1.859, − , respectively. The bond lengths of the BP triple bonds that are obtained from DFT calculations are shorter than those that are acquired experimentally. − , …”

“…Since the pioneering work of Coates and Livingstone on the preparation of phosphinoborane (Ph 2 BPPh 2 ) in 1961, many new examples of the B–P single bond have been found. , These are reviewed in the literature. − In addition to that of the molecules that feature a B–P single bond, the synthesis of compounds that feature the BP double bond character has attracted the interest of inorganic and organometallic chemists. − Synthesis of these molecules, which have either the B–P single bond or the BP double bond, is of interest because they are respectively isoelectronic with ethane and ethylene, from the valence-electron viewpoint. It is therefore expected that the structural, physical, and chemical properties of BP species are all similar to those of CC.…”

Base‐Stabilized Phosphinidene Boranes by Silylium‐Ion Abstraction

“…In the 11 B NMR spectrum, a broad signal at δ =61.1 ppm, which is characteristic of monomeric phosphinoboranes, is observed. On cooling, the broad signals in the 31 P NMR spectrum decrease in linewidth (55.4 and 44.8 Hz at 193 K), indicative of rotation about the P−B bond becoming slow on the NMR timescale …”

Synthesis of a transition-metalated phosphinoborane dimer

“…The interests in the borane adducts of the transition-metalated phosphorus compounds emerge, in part, from their isoelectronic relationship to the transition-metalated carbon compounds. One of the most notable differences between the P-B and the C-C compounds is that the P-B compounds isoelectronic to alkenes or alkynes have greater tendency to aggregate in a head-to-tail fashion (Chart 1) [2][3][4][5][6][7]. Depending on the preparative conditions adopted and on substituents on both the phosphorus and the boron atoms, the resulting compounds vary from dimers to polymers in a cyclic or linear form.…”