posted on 2021-05-26, 22:31authored byYibin Xue, Guangbin Dong
Herein, we describe the first total
synthesis of sesquiterpene
penicibilaenes A and B through a “C–C/C–H”
approach. In the “C–C” stage, the Rh-catalyzed
“cut-and-sew” transformation between trisubstituted
alkene and cyclobutanone has been employed to construct the unique
tricyclo[6.3.1.01,5]dodecane skeleton and the all-carbon
quaternary center. Critical linker and Lewis acid effects have been
identified for the C–C activation process. In the “C–H”
stage, a desaturation relay-based strategy involving consecutive ketone
α,β-dehydrogenation and β-functionalization has
been adopted to introduce the 1,3,5-triad stereocenters to the core.
The synthesis of penicibilaenes A and B has been completed in 13 and
14 steps, respectively, in the longest linear sequence.