B12H11-containing guanidinium derivatives by reaction of carbodiimides with H3N–B12H11(1−). A new method for connecting boron clusters to organic compounds

The reaction of B12H11NH3(1−) with carbodiimides can form guanidinium salts containing the boron cluster. Depending on the side chains of the carbodiimide, these derivatives of the B12H12(2−) cluster can be uncharged or can carry an overall positive or negative charge. This reaction allows the preparation of B12H11NH3- derivatives with aliphatic side chains, in contrast to the acylation reaction of B12H11NH3- and the formation of Schiff bases, both of which are successful only with aromatic acid chlorides or aromatic, respectively, α,β-unsaturated aldehydes. The acylation of B12H11NH3- with benzoyl chloride gives an N-protonated form of an imidoacid, carrying a single overall charge.

Graphical abstractThe B12H11NH3- boron cluster can be easily connected to organic substituents via the connection to carbodiimides. This easy and convenient synthetic way allows the formation of a wide variety of several new boron cluster containing organic compounds for possible use in BNCT (boron neutron capture therapy).Figure optionsDownload full-size imageDownload as PowerPoint slide