Coordinating Ability of the Iminophosphorane Group in ortho‐Carborane Derivatives

Abstract

Abstract:The coordinating ability of the nitrogen donor atom of C-carboranyl iminophosphoranes was studied in different ligand systems. The analysis of organotin derivatives of the unsubstituted iminophosphorane I1 (SnMe 3 I1 and SnClMe 2 I1) and the comparison with the non-carboranyl analog (SnClMe 2 I3), reveals the reduced donor capacity of the nitrogen atom due to the closo-carborane group. To promote the coordination of this weak donor atom, new phosphine-iminophosphorane ligands (IP1 and IP2), with an extra -PPh 2 group on the other cage carbon atom, were synthesized and structurally characterized. The analysis of the products formed by the reaction of these ligands with the metal precursor cis-

Synthesis, Structure, and Spectroscopy of the Biscarboranyl Stannylenes (bc)Sn·THF and K2[(bc)Sn]2 (bc = 1,1′(ortho-Biscarborane)) and Dibiscarboranyl Ethene (bc)CH═CH(bc)

“…The first isolable carboranyl tin structures were the organotin complexes [ o -C 2 B 10 H 10 (CH 2 NMe 2 )­SnR 2 Br (R = Me or Ph; X = Cl or Br) which feature a Sn­(IV) bonded to a carbon vertex and stabilized by a Lewis basic −CH 2 NMe 2 chelating group (Table and ref ) . In general, the majority of the tin-carborane complexes are achieved through an initial lithiation step in the stannylation of the C–H vertices of the carboranes cages. ,− …”

“… 26 In general, the majority of the tin-carborane complexes are achieved through an initial lithiation step in the stannylation of the C–H vertices of the carboranes cages. 16 , 23 − 38 …”