ol701697r_si_003.pdf (432.69 kB)
Functionalized Cyclobutanes via Heck Cyclization
journal contribution
posted on 2007-10-25, 00:00 authored by Anna Innitzer, Lothar Brecker, Johann MulzerHeck-type 4-exo-trig cyclization of linear 2-enol triflate-1,5-hexadienes provides functionalized methylene cyclobutanes. Intramolecular palladium
coordination can initiate β-hydride elimination leading to 1,2-dimethylene cyclobutane derivatives, which are obtained with high selectivity if
substrates having a geminal diphenyl group at Cα are used. In parallel, formal 5-endo-trig cyclization and β-hydride elimination form 1-methylene
cyclopent-2-en derivatives.