Regioselectivity of Diels-Alder reactions of a surfactant 1,3-diene with surfactant dienophiles
作者:David A. Jaeger、Jinkang Wang
DOI:10.1021/jo00076a040
日期:1993.11
The ability of aqueous surfactant aggregates to control the regiochemistry of Diels-Alder reactions was investigated with surfactant 1,3-diene 4-[p-[[3-[(p-octylphenyl)thio]-1,3-butadien-2-yl]thio]phenyl]-N,N,N-trimethyl-1-butanaminium bromide (6), derived in situ by thermal extrusion of SO2 from 4-[[[1,1-dioxo-4-[(p-octylphenyl)thio]-2,5-dihydrothiophen-3-yl]thio]phenyl]-N,N,N-trimethyl-1-butanaminium bromide (8), and surfactant dienophiles (E)-6-[[[2-(alkoxycarbonyl)ethenyl]carbonyl]-oxy]-N,N,N-trimethyl-1-hexanaminium bromide (7) (a, R = Me; b, R = Bu; c, R = C8H17). In each case an excess of 1-[[p-[(4-trimethylammonio)butyl]phenyl]thio]-2-[(p-octylphenyl)thio]-4-(alkoxycarbonyl)-5-[[6-(trimethylammonio)hexoxy]carbonyl]-1-cyc lohexene dibromide (16) over 1-[[p-[(4-trimethylammonio)butyl]phenyl]thio]-2-[(p-octylphenyl)thio]-4-[[6-(trimethylammonio)hexoxy]carbonyl]-5-(alkoxycarbonyl)-1-cyc lohexene dibromide (17) was obtained, consistent with the reaction of 6 and 7 within a mixed aggregate in their preferred orientations at the aggregate-H2O interface. The cyclohexene rings of 16 and 17 have different conformational character in chloroform resulting from supramolecular effects within reversed micelles.