Synthesis and Reduction of Super‐Bulky Bis(anilido)acridanide Aluminium Complexes

ABSTRACT Super‐bulky bis(anilido)acridanide pro‐ligands (NNN Ar )H 3 (NNN Ar = 4,5‐bis(anilido)‐2,7,9,9‐tetramethylacridanide, anilido = NAr, Ar = DCHP, 2,6‐dicyclohexylphenyl; TCHP, 2,4,6‐tricyclohexylphenyl) have been prepared in high yields. The reaction of (NNN TCHP )H 3 with trimethylaluminium affords bimetallic complex [Al 2 Me 3 (NNN TCHP )] which reacts with iodine to form the corresponding monometallic complex [Al(NNN TCHP )(I) 2 ]. The reduction of [Al(NNN TCHP )(I) 2 ] with sodium and potassium containing reducing agents was explored. From potassium reductions, only complexes K[Al(NNN TCHP )(I)] (from K/KI) and [Al(NNN TCHP )(TMEDA)] (from KC 8 /TMEDA, TMEDA = N,N,N’,N’ ‐tetramethyl ethylenediamine) could be isolated. In contrast, aluminium(III) hydride [Na(C 6 H 6 )][Al(NNN TCHP )(H)] was formed from reduction of [Al(NNN TCHP )(I) 2 ] in benzene with excess sodium metal (mirror). This complex is unstable and readily decomposes in the presence of ethers, such as 2.2.2‐cryptand, to give the aluminium(III) complex [Al(NNN TCHP )(2.2.2‐cryptand)].