4-[2,4,6-TRIS(1-METHYLETHYL)BENZOYL]BENZOIC ACID (S)-(-)-PROLINE

The title compound, C23H28O3.C5H9NO2, is a 1:1 complex of the benzoic acid derivative and the (S)-proline zwitterion, with two formula units in the asymmetric unit (with pseudo-symmetry relationships between th e separate components). The ketone carbonyl group in each benzoic acid molecule deviates slightly from a position normal to the plane of the triisopropylphenyl ring; the deviations (of about 16 degrees) are in opposite senses in the two molecules, so that the molecules have oppos ite conformational chiralities, leading to a nearly racemic photoprodu ct on solid-state photolysis.