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The rearrangements of dihydrobetulin, dihydrobetulinic acid, and abeo-lupane epoxides under acidic conditions (HCl, montmorillonite K10, and BF3·Et2O) were studied. The treatment of dihydrobetulin with HCl or K10 produced abeo-lupane olefins. Their epoxidation afforded epoxides, which, in the presence of protic or Lewis acids, rearranged to dienes or lupanes bearing a bicyclo[3.3.1]nonane fragment. The structure of final products depended on the nature of the catalyst. The HCl promoted 1,4-elimination of water, whereas in the presence of BF3·Et2O bond migration took place preferentially. Montmorillonite K10 favored cyclization to bicyclononane.

Amide-directed hydrocarbonylation of 3-butenamide(1) catalyzed by rhodium complexes such as RhCl(PPh 3 ) 3 , RhCl(CO)(PPh 3 ) 2 , HRh(CO)(PPh 3 ) 3 , and Rh 4 (CO) 12 gives a mixture of 3,4-dihydro-2-pyridone (2), 4-methyl-3-pyrrolin-2-one (3), and a unique heterodimer, 6-(4-methyl-2-oxo-3-pyrrolin-1-yl)-2-piperidone (4)