OH-Based Anion Recognition

Hydroxyl groups of alcohol, phenol, and silanols as H-bonding donors have also been used for the construction of anion receptors. In this context. Smith et al. reported that some simple and commercially available dihydroxybenzenes, such as 97-99, exhibited relatively high tunable anion selectivity [168, 169]. For example. 

Shinmyozu and co-workers prepared photo-switchable chiral receptor trans- Q9 by linking two chiral 2,2 -dihydroxy-l,l -binapthyl (BINOL) groups with a stiff-stilbene core [172]. This compound could be photochemically isomerized to cis-109. The tmns- Q9 binds fluoride or chloride ions to form 1 1 complexes with 

Kondo and co-workers studied the anion binding of D-ribose-based epimers 110 and 111 [173]. Their anion-binding abilities were in the order of 

AcO H2P04 Cr Br, and in CDCI3, the of 111 K = 2,450 M ) for AcO was two order higher than that of 110 (Aia = 72 M ). Kondo et al. also prepared silanols 112-114 [174, 175]. They found that, compared to 112 and 113, 114a and 114b had a higher affinity for halides because they could utilize four OH groups to stabilize one halide ion. 

Bowman-James K, Bianchi A, Garcia-Espana E (eds) (2012) Anion coordination chemistry. Wiley VCH, Welnheim 

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