Generation and Trapping of Labile Anions

Boric acid, B(OH)3 (also known as orthoboric acid and commonly rewritten as H3BO3) generally behaves not as a Brpnsted acid to form the conjugate-base anion BO(OH)2, but rather as a Lewis acid to give the tetrahedral anion B(OH)4 [32]. In dilute aqueous 

Allophanic acid (ureidoformic acid, NH2CONHCOOH) is an elusive compound which is known only in the form of its derivatives. Ester-like organic allophanates have been prepared from primary, secondary, and tertiary alcohols and from phenols [39], whereas inorganic allophanate salts are unstable and easily hydrolyzed by H2O to CO2, urea, and carbonate [40]. The first two crystalline complexes containing host lattices built of urea molecules and allophanate ions were prepared and structurally characterized in 1995 [5h]. 

while the thiouredio end is connected to the other thiourea molecule by a pair of strong -S hydrogen bonds in a shoulder-to-shoulder manner with ring motif D. 

As a result, an essentially planar host layer with large voids E is generated. The mean plane of the host layer matches the (101) family of planes, with an interlayer spacing of about 7.9 A for accommodation of the organic cation, which has two alkyl legs inserted into the void of an adjacent layer. 

The formation of the elusive 3-thioallophanate anion by condensation between thiourea and the bicarbonate anion in methanol is noteworthy, as our attempted synthesis via 

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