Dilithiodiborane(6) (Li2B2H4). An experimentally viable species with a B = B double bond. Planar no-bond-double-bond isomers with pentacoordinate boron?

Infinite, Linear, Unbranched Borynide Chains in LiBx—Isoelectronic to Polyyne and Polycumulene

“…[30] These bond distances are only marginally shorter than the observed single bond distances in organic derivatives of B 2 H 4 (1.698(4), 1.711(6) ), B 2 F 4 (1.67(5), 1.72 ), B 2 Cl 4 (1.75(5), 1.70(7) ), and B 2 Br 4 (1.69(2) ). A comparison of the boron ± boron bond distances for different neutral, singly and doubly reduced organodiborane(4) compounds [31] reveals a shortening upon going from the neutral species (1.706(12) and 1.724 (9) , bond order of one) to the doubly reduced species (1.627(9) and 1.636 (11) , bond order two).…”

Infinite, Linear, Unbranched Borynide Chains in LiBx—Isoelectronic to Polyyne and Polycumulene

“…[30] These bond distances are only marginally shorter than the observed single bond distances in organic derivatives of B 2 H 4 (1.698(4), 1.711(6) ), B 2 F 4 (1.67(5), 1.72 ), B 2 Cl 4 (1.75(5), 1.70(7) ), and B 2 Br 4 (1.69(2) ). [30] These bond distances are only marginally shorter than the observed single bond distances in organic derivatives of B 2 H 4 (1.698(4), 1.711(6) ), B 2 F 4 (1.67(5), 1.72 ), B 2 Cl 4 (1.75(5), 1.70(7) ), and B 2 Br 4 (1.69(2) ).…”

A Simple Link between Hydrocarbon and Borohydride Chemistries

“…Moreover, Li 2 B 2 H 4 was computationally found to be an experimentally viable species according to Kaufmann and Schleyer. [26] Then, sequential substitution of each B À B bond in B 2 H 4 2À leads first to B 2 H 5 À and then to B 2 H 6 , the well-known diborane(6) molecule with two 3c-2e B-H-B bonds. [1,27] Ethyne: Starting from C 2 H 2 , one gets anionic species CBH 2 À and B 2 H 2 2À with carbon boron and boron boron triple bonds, respectively.…”