Silicon Tetrahydroborate and Silylene Dihydroborate with Interelement B–H–Si and B═Si Bonds

Abstract

Reactions of laser-ablated boron atoms with SiH4 molecules gave silylene dihydroborate (H2BSiH2) in excess argon, which rearranged to silicon tetrahydroborate [Si­(μ-H)2BH2] upon 300–350 nm irradiation. These reaction products were identified by functional group infrared frequencies, isotopic shifts, and comparison to infrared frequencies calculated by using density functional theory. It is found that H2BSiH2 has planar doublet ground state with electron-deficient B–Si double-bond character. Bonding analysis for Si­(μ-H)2BH2 shows that 3c–2e B–H–Si bond is formed by accepting electrons donated from B–H σ bond.

Copper‐Catalyzed Monoborylation of Silylalkynes; Regio‐ and Stereoselective Synthesis of (Z)‐β‐(Borylvinyl)silanes

“…In Figure 2, orbital energies of the catalyst and substrate were calculated and the most dominating orbital interaction is due to the Cu À B s-bond (HOMO) of the catalyst and the p* orbital (LUMO) of the substrate. Thus, the Bpin moiety of the catalyst could be preferably transferred to the C b of the substrate because C b has larger a MO coefficient than C a in the LUMO of the substrate, [14] suggesting the observed b-regioselectivity.…”

Infrared Spectra and Theoretical Calculations of BSe2 and BSe2–: The Pseudo-Jahn–Teller Effect

“…Our experimental method has been described in detail previously. , Briefly, the 1064 nm laser beam (Nd:YAG laser fundamental, 10 Hz repetition rate, and 8 ns pulse width) is focused on a rotating boron target. Laser-ablated natural boron atoms n B (Aldrich, 80.4% 11 B, 19.6% 10 B), enriched 10 B atoms (Eagle Pitcher, 93.8% 10 B, 6.2% 11 B), or enriched 11 B atoms (Eagle Pitcher, 2.5% 10 B, 97.5% 11 B) have been codeposited with the H 2 Se/Ar mixture onto a 5 K CsI window cooled by means of a closed-cycle helium refrigerator (Sumitomo Heavy Industrious).…”

Main Group Multiple Bonds for Bond Activations and Catalysis

“…Examples of group E 13 –E 14 multiple bonds are also limited to a handful of examples and as such the reactivity of these compounds is largely unknown. Attempts to isolate borasilenes, that is compounds containing B=Si double bonds, have been achieved through matrix isolation techniques [55] . To date, only one neutral borasilene ( 21 ) [56] and one Lewis base stabilised borasilene ( 25 ) [57] exist in the condensed phase.…”

“…Attempts to isolateb orasilenes, that is compoundsc ontaining B=Si doubleb onds, have been achieved through matrix isolation techniques. [55] To date, only one neutral borasilene (21) [56] ando ne Lewis base stabilised borasilene (25) [57] exist in the condensed phase. Reactivity studies of 21 towards chalcogens revealed the formationo f three-membered rings with sulfur (22)a nd selenium( 23), whilst with oxygen (24)afour-membered ring, with loss of the BÀSi bond, was found (Scheme6a).…”