Enantioselective Recognition of Amino Acids by Axially-Chiral π-Electron-Deficient Receptors

cyclo-Bis(paraquat-m-terphenylene) tetrakis(hexafluorophosphate) tetrahydrate

“…Data collection: SMART (Siemens, 1996); cell re®nement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to re®ne structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL, PARST (Nardelli, 1995) and PLATON (Spek, 1990 (Amabilino & Stoddart, 1995). They have potential uses in resolving racemic substrates containing π-electronrich aromatic rings (Asakawa et al, 1996) and function as non-sequence specific DNA photo cleaving agents (Lorente et al, 1999). cyclo-Bis(paraquat-m-terphenylene) is such a tetracationic cyclophane synthesized by refluxing an equimolar mixture of m-terphenyldibromide (Hart & Rajakumar, 1995) and 4,4′-bipyridine in acetonitrile for 48 h followed by column chromatography and counter-ion exchange with NH 4 PF 6 .…”

Chiral Heterocycle-Based Receptors for Enantioselective Recognition

“…Stoddart et al [63] have developed new axially-chiral tetracationic cyclophanes, (R)-14.4PF6 and (R,R)-16.4PF6 (Scheme 2). Tetracationic cyclophane, (R)-14.4PF6 was obtained by the reaction of (R)-12 and 13.2PF6 and similarly D2 symmetric tetracationic cyclophane, (R,R)-16.4PF6 was synthesized using the treatment of (R)-12 and (R)-15.2PF6.…”

The Click Reaction as an Efficient Tool for the Construction of Macrocyclic Structures

“…We have recently reported the design and synthesis of a chiral click macrocycle behaving as a chiroptical sensor for the detection of halide anions (Figure 4) [63]. This work is part of our activity in the field of binaphthyl-based chiral macrocycles for chiroptical sensing and chiral nanostructuring [64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80]. The macrocycle 17 incorporates a binaphthyl (Binol) unit; the skeleton is not composed entirely of aromatic-type carbon atoms.…”