REGIOSELECTIVE FUNCTIONALIZATION .6. MIGRATORY PREFERENCES IN HYDROXYLAMINE-O-SULFONIC ACID AND SCHMIDT REARRANGEMENTS OF 7-SUBSTITUTED NORCAMPHORS

Hydroxylamine-O-sulfonic acid reacted with syn-7-X- and anti-7-Y-subst ituted norcamphor derivatives [X = H, OMe, Cl, Br, OTos; Y = H, COOMe, Cl, Br, Tos, COOMe(5-exo-Br)], to give solely bridgehead migrated 2-a zalactams, except for minor amounts of methylene migrated S-azalactams from norcamphor (1) and the syn-7-Br ketone 19. Schmidt reactions of the same ketones provided varying mixtures of methylene and bridgehead migrated lactams, except for norcamphor (1) and anti-7-Br ketone 31, which provided solely 3-azalactams. Significant ratios (> 0.4) of brid gehead migration to cleavage products were observed in the Schmidt rea ctions only with 7-OTos ketones 22 and 24 with exo-5-bromo-anti-7-meth oxycarbonyl ketone 37. The Schmidt rearrangements most likely involve iminodiazonium ion intermediates in light-of the large amounts of clea vage observed relative to lactam formation and the insensitivity of me thylene migration to the substituent size in the reactions of syn-7-su bstituted norcamphors.