Synthesis and Reactivity of N-Substituted-1-amino-2-(methylsulfonyl)-3-phenyl-2-propenes

Article abstract of DOI:10.1021/jo00384a030

The synthesis of 3-bromo-2-(methylsulfonyl)-1-phenyl-1-propene (1b) is described.Reaction of the allyl bromide 1b with tert-butylamine, diisopropylamine, glycine methyl ester, and piperidine in benzene solution yielded mixtures of direct substitution (S_N2) and substitution-rearrangement (S_N2') products, 2 and 3, respectively.The S_N2:S_N2' ratio ranged from 1:4 for reaction of 1b with glycine methyl ester to greater than 20:1 for the reaction with diisopropylamine.Amine hydrochloride promoted amine exchange reactions of N,N-diisopropyl-1-amino-2-(methylsulfonyl)-3-phenyl-2-propene (2a) and the amine exchange and aminotropic rearrangement reactions of the thermodynamically less stable N-tert-butyl-1-amino-2-(methylsulfonyl)-1-phenyl-2-propene (3b) are described.Evidence for acid-catalyzed aminotropic rearrangement and amine exchange reactions (3-->2) is presented.Equilibrium constants for reactions of 2a and of 2b with piperidine hydrochloride in chloroform solution were determined.