Mn(I)-catalyzed selective functionalization of alkynes permits the convenient synthesis
of substituted alkenes with high step and atom economies. Although the insertion of
five-membered chelated manganacycle intermediates into alkynes has been widely reported,
nonchelated Ar–Mn(I) species originating from commercially available arylboronic acids
are unprecedented. Our new protocol achieved a challenging hydroarylation of unsymmetrical
1,3-diynes with arylboronic acids with complete regio-, stereo-, and chemoselectivity
to give a wide array of trisubstituted conjugated (Z)-enynes in moderate to good yields.
Key words
arylboronic acids - alkynes - C–H activation - manganese catalysis - diynes - enynes