PALLADIUM-PROMOTED CYCLIZATION REACTIONS OF AMINOALKENES

Article abstract of DOI:10.1016/S0022-328X(00)85965-3

The trifluoromethanesulphonate salts of the aminoalkenes CH2=CH(CH2)3NH2, its 2-methyl, 2,2-dimethyl and N-iso-propyl-derivatives, and CH2=CH(CH2)4NH2 cyclize in the presence of and a nitrogen base to produce the corresponding C- or N-substituted 2-methylpyrrolidines and 2-methylpiperidine, E-CH3CH=CH(CH2)3NH2 produces 2-ethylpyrrolidine and a small amount of 2-methylpiperidine.The regio-selectivity of these reactions differs from that observed for the cyclization of the same substrates promoted by ^2-: (1) the palladium reaction with 2-methylpent-4-enylamine produces ca. a 4 : 6 ratio of cis- and trans-2,4-dimethylpyrrolidine while with platinum the converse is true; (2) there is a more marked tendency for attack of the amine at the more substituted alkene carbon atom in the palladium than in the platinum reactions.