Combined C-H activation/cope rearrangement as a strategic reaction in organic synthesis: total synthesis of (-)-colombiasin a and (-)-elisapterosin B.
The total synthesis of (-)-colombiasin A (2) and (-)-elisapterosin B (3) has been achieved. The key step is a C-H functionalization process, the combined C-H activation/Cope rearrangement, between methyl (E)-2-diazo-3-pentenoate and 1-methyl-1,2-dihydronaphthalenes. When the reaction is catalyzed by dirhodium tetrakis((R)-(N-dodecylbenzenesulfonyl)prolinate), Rh(2)(R-DOSP)(4), an enantiomer differentiation step occurs where one enantiomer of the dihydronaphthalene undergoes the combined C-H activation/Cope rearrangement while the other undergoes cyclopropanation. This sequence controls the three key stereocenters in the natural products such that the remainder of the synthesis is feasible using standard chemistry.
Davies
Huw M L
HM
Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY 14260-3000, USA. hdavies@acsu.buffalo.edu
Dai
Xing
X
Long
Matthew S
MS
D001952:Bridged-Ring Compounds / Q000138:chemical synthesis*; D004224:Diterpenes / Q000138:chemical synthesis*; D013237:Stereoisomerism
D001952:Bridged-Ring Compounds; D004224:Diterpenes; C408889:colombiasin A; C414524:elisapterosin B