One-Pot Synthesis of [(C6F5)2BH2]− from C6F5MgBr/BH3·SMe2 and Its in Situ Transformation to Piers’ Borane

Depending on the crystallization procedure, the one-pot reaction between 2 C 6 F 5 MgBr, 1 BH 3 ·SMe 2, and 1 Me 3 SiCl furnishes the hydridoborate salts [Mg 2 (Et 2 O) 3 Br 2 Cl][(C 6 F 5 ) 2 BH 2 ] and [Mg(Et 2 O) 2 ][(C 6 F 5 ) 2 BH 2 ] 2, both of which are convenient starting materials for the in situ generation of Piers’ borane (C 6 F 5 ) 2 BH.