Multi-Talented Bismuthinidenes: Double C(sp3)─I Bond Activation Using Single or Two Bi Centers

Abstract

The reaction of [2,6-(DippN = CH)₂C₆H₃]Bi (1Dipp, Dipp = 2,6-iPrC₆H₃) with CH₂I₂ proceeded via double C─I bond activation yielding [2,6-(DippN = CH)₂C₆H₃]Bi(μ-(Bi,N)─CH₂)I₂ (3). By contrast, the reaction of 1Dipp with 1,2-diiodoethane provided [2,6-(DippN═CH)₂C₆H₃]BiI₂ (1DippI₂) and ethene. The tert-butyl analogue [2,6-(tBuN═CH)₂C₆H₃]Bi (1tBu) reacted with CH₂ClX to give [2,6-(tBuN═CH)₂C₆H₃]Bi(CH₂Cl)X (X═I (4) or Cl (5)). Further, its reactivity with CH₂I₂ was sensitive towards the stoichiometry since using a 1:1 ratio gave a mixture of dinuclear complex {[2,6-(tBuN═CH)₂C₆H₃]Bi(I)}₂(μ-(Bi,Bi)─CH₂) (6) and [2,6-(tBuN═CH)₂C₆H₃]Bi(CH₂I)I (7). The reaction could be shifted in favor of 7 using an excess of CH₂I₂, but with 0.45 eq. of CH₂I₂ compound 6, as a product of double C─I bond activation mediated by two Bi atoms was isolated as the main product.

Keywords: bismuthinidene; bond activation; low‐valent p‐block elements; oxidative addition; pincer ligands.