Abstract
Enantioselective syntheses of (-)-Δ 8 -tetrahydrocannabinol ((-)-Δ 8 -THC) and (-)-Δ 9 -THC have been achieved in eight and 10 steps, respectively, from a known cinnamic acid. The syntheses take advantage of an enantioselective N-heterocyclic carbene (NHC)-catalyzed (4 + 2) annulation between donor-acceptor cyclobutanes and cinnamoyl fluorides to construct the highly enantioenriched cycloxyl β-lactone shown. Having constructed this A-ring precursor, elaboration to (-)-Δ 8 -THC is achieved through β-lactone alcoholysis followed by oxidation, dual decarboxylation, trimethylation, and cationic cyclization. Finally, the conversion to (-)-Δ 9 -THC is achieved with established chemistry.
Original language | English |
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Pages (from-to) | 1212-1215 |
Number of pages | 4 |
Journal | Organic Letters |
Volume | 21 |
Issue number | 4 |
DOIs | |
Publication status | Published - 1 Jan 2019 |