Surprises in a ‘Simple' System: 2,4‐Diaminobenzenesulfonic Acid

Abstract

Dedicated to Professor Jack D. Dunitz on the occasion of his 80th birthdayThe search for the polymorphic forms of 2,4-diaminobenzenesulfonic acid (DBSA), known to exist since 1880, has revealed a surprisingly rich solid-state system for such a simple molecule. A monohydrate, a dimoiric hydrate, an anhydrate and two polymorphic forms of the hydrochloride of this material have thus far been prepared. Their characterization by microscopic and thermal methods, FT-IR spectroscopy, and single-crystal structure determination are described.

4-Amino-3-ammoniobenzenesulfonate

“…1)is a zwitterion of 4-amino-3-ammoniobenzenesulfonate. The bond lengths and angles in (I) are normal and comparable with those observed in the related compounds(Rubin-Preminger & Bernstein, 2003). In the crystal structure, intermolecular N-H•••O hydrogen bonds generate an extensive three-dumensional network which consolidate the crystal packing.…”

3-Aminobenzenesulfonic Acid: A Disappearing Polymorph

“…In 1965, Hall and Maslen 16 reported the crystal structure of the anhydrate (Refcode ANISAC) as "colorless orthorhombic needles elongated in the c direction" (Table 1), with no mention of the sesquihydrate. In our continuing investigation of the various crystal forms of the mono-and diaminobenzenesulfonic acids, 17 we have isolated two new polymorphic forms (Form II and Form III) of the 3-aminobenzenesulfonic acid anhydrate. Form II was grown using the same method described by Hall and Maslen, 16 and Form III was grown by using a structurally similar additive (m-toluenesulfonic acid, 2) in an effort to prevent the growth of Form II and to reobtain Form I.…”

Joel Bernstein: a crystal engineer's crystal engineer

“…His primary example was the work by the great German crystallographer P. Groth, whose five volumes were in his library. Examples of historically significant systems which he investigated with numerous coauthors are '2,4-Diaminobenzenesulfonic acid -an old system with some new surprises' (Rubin-Preminger & Bernstein, 2003), 'Groth's original concomitant polymorphs revisited' (Rafilovich et al, 2005), 'Disappearing and reappearing polymorphs. The case of benzocaine:picric acid' (Henck et al, 2001) and '3-Aminobenzenesulfonic acid: a disappearing polymorph' (Rubin-Preminger & Bernstein, 2005).…”