Synthesis of Derivatives of (1R)-(-)- and (1S)-(+)-10-Camphorsulfonic Acid

The preparation of optically active (camphorsulfonyl)oxaziridines from commercially available (1R)-(-) and/or (1S)-(+)10-camphorsulfonic acid provides a clear demonstration of the lack of relationship between absolute configuration and optical rotation. The parent sulfonic acid can be converted to the corresponding acid chloride and then to the sulfonamide, sulfonylimine, and finally to an oxaziridine in a series of practical organic laboratory experiments. The absolute configuration remains the same through this series of transformations, but the sign of the optical rotation is reversed from the sulfonamide to the sulfonylimine, and again from the sulfonylimine to the oxaziridine. The latter two intermediates are readily purified by crystallization, and their optical rotations are easily measured.