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As part of our efforts in the chemistry of main group platforms that support anion sensing and transport, we are now reporting the synthesis of anitmony-based bidentate Lewis acids featuring the o -C 6 F 4 backbone. These compounds can be easily accessed by reaction of the newly synthesized o -C 6 F 4 (SbPh 2 ) 2 ( 5 ) with o -chloranil or octafluorophenanthra-9,10-quinone, affording the corresponding distiboranes 6 and 7 of general formula o -C 6 F 4 (SbPh 2 (diolate)) 2 with diolate = tetrachlorocatecholate for 6 and octafluorophenanthrene-9,10-diolate for 7 , respectively. While 6 is very poorly soluble, its octafluorophenanthrene-9,10-diolate analog 7 readily dissolves in CH 2 Cl 2 and undergoes swift conversion into the corresponding fluoride chelate complex [ 7 -μ 2 -F] − which has been isolated as a [ n Bu 4 N] + salt. The o -C 6 H 4 analog of 7 , referred to as 8 , has also been prepared. Although less Lewis acidic than 7 , 8 also forms a very stable fluoride chelate complex ([ 8 -μ 2 -F] − ). Altogether, our experiental results, coupled with computational analyses and fluoride anion affinity calculations, show that 7 and 8 are some of the strongest antimony-based fluoride anion chelators prepared to date. Another notable aspect of this work concerns the use of the octafluorophenanthrene-9,10-diolate ligand and its ablity to impart advantageous solubility and Lewis acidity properties.