Catalytic [6π+2π]-cycloaddition of alkynes, 1,2- and 1,3-dienes to 1,3,5-cycloheptatrienes involving Ti complexes

Novel two-component Ti-based catalytic systems, R2TiCl2–R′nAlCl3−n (R=acac, iPrO, tBuO; R′=Et, Bu, n=2, 3), for [6π+2π]-cycloaddition of acetylenes and 1,2- and 1,3-dienes, including functionally substituted ones, to 1,3,5-cycloheptatrienes to give bi-, tri-, and polycyclic hydrocarbons were developed.