Synthesis of 1,8,9,16-Tetrakis(trimethylsilyl)tetra-cata-tetrabenzoquadrannulene
摘要:
The synthetic efforts that yielded the first stable [4]circulene, 1,8,9,16-tetrakis(trimethylsilyl)tetra-cata-tetrabenzoquadrannulene (TMS4-TBQ, 1), are reported. The synthesis and characterization of different intermediates are described. The cyclotrimerization of the key precursor tetraalkyne was explored using Rh(I), Ni(0), and Co(I) catalysts. The ultimate product 1 was isolated only after oxidative demetalation of cobalt complexes.