Preparation and crystal structures of two 3‐anthracenyl isoxazolyl sulfonamides

Lateral metalation and oxidation of 3‐(9′‐anthryl)‐isoxazoles ( 1 ), using Davis' oxaziridine ( 6 ), produced the desired hydroxylation ( 2 ), along with sulfonamide adduct ( 3 ), and in the case of the use of butyl lithium as base, butyl addition products ( 4 ) and ( 5 ). Structures of isoxazole sulfonamides ( 3a ) and ( 5a ), were obtained as the SR/RS‐diastereomer, however, studies indicate that this is a consequence of the crystallization process. Metalation studies with isoxazole ( 8 ) demonstrate that hydroxylation ( 9 ), can be carried out cleanly, minimizing formation of ( 10 ), using camphorsulfonyloxaziridine ( 7 ) as an electrophile.