Salts with the Triborate Anion [B3O3F2(OH)2]–: A Combined Experimental and Theoretical Study

Abstract Reactions of [3‐NC‐B 11 F 10 ] 2– with aqueous bases resulted in a cluster degradation. From the reaction mixtures, salts of the [B 3 O 3 F 2 (OH) 2 ] – anion ( 1 ) with [Ph 4 P] + or [Ph 3 MeP] + as countercations were isolated. Both salts were investitgated by single‐crystal X‐ray diffraction. In the solid state the triborate anions form infinite hydrogen‐bonded chains. In the [Ph 4 P] + salt the anions and the chains are coplanar, whereas in the [Ph 3 MeP] + salt the planes of the anions are twisted against each other. The bonding parameters of the anion are compared to values of the related [B 3 O 3 (OH) 4 ] – anion ( 2 ) and to values derived from density functional calculations. In addition, the triborate anion 1 was characterized by 11 B and 19 F NMR spectroscopy as well as by MALDI mass spectrometry. The experimental chemical shifts are compared to calculated values (DFT‐GIAO).(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)