Tris tetrachlorobenzenediolato Phosphate Anion TRISPHAT

In the past decade many groups from aU over the world were interested in the use of the A-TRISPHAT anion to differentiate chiral racemic compounds by H-and 

NMR techniques, or by resolving them through anion metathesis. We have outlined most of these examples in Table 4.1. 

To avoid an exhaustive description and repetition for every single species displayed in Table 4.1, we have selected some compounds of different type and geometry where an appropriate explanation of the chiral recognition process between the optically pure anion and the chiral compound will be presented. 

Although it is not surprising that Ru-tris(diimine) complexes can easily be differentiated and/or resolved using A-TRISPHAT as chiral auxiliary, (see Section 4.1.2), yet the resolution of the dinuclear ruthenium complex fran5-[bis(Cp Ru)carbazolyl][PFg] 

The structure of 4.18a shows that the two Cp Ru units are bonded to the carbazolyl ligand and are disposed in a trans fashion. Most remarkable is the interaction between the TRISPHAT anion and the cationic metal complex. There are two n-n interactions between one of the tetrachloro-benzene rings of A-TRISPHAT and the two t/ -Cp Ru units of two cationic metal complexes with (J = 3.55 (1) A a = 19.24°) for the C(13)-C 

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Lacour et al. have shown that the ion pairing of Bulman Page s iminium cation 66 with a tris(tetrachlorobenzenediolato)phosphate(v) (TRISPHAT) anion allows the use of strict biphasic conditions leading to higher enantioselectivities when compared to a tetraphenylborate counterion (Scheme 26) <2002TL8257>. 

The Z)3-symmetric TRISPHAT anion 88, tris(tetrachlorobenzenediolato)phosphate, is chiral and configurationally stable. It can be resolved by association with chiral ammonium salts such as cinchonidine <1997AGE608, 2004JOC8521>. TRISPHAT 88 displays high selectivity for cinchonidine and does not associate with the related diasteromer cinchonine <1998TL4825>. The selective ion pairing behavior of TRISPHAT has been exploited in... 

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