A novel, mixed‐ligand chiral rhodium(II) catalyst, Rh2(S‐NTTL)3(dCPA), has enabled the first enantioselective total synthesis of the natural product piperarborenine B. A crystal structure of Rh2(S‐NTTL)3(dCPA) reveals a “chiral crown” conformation with a bulky dicyclohexylphenyl acetate ligand and three N‐naphthalimido groups oriented on the same face of the catalyst. The natural product was prepared on large scale using rhodium‐catalyzed bicyclobutanation/ copper‐catalyzed homoconjugate addition chemistry in the key step. The route proceeds in ten steps with an 8 % overall yield and 92 %
A Mixed‐Ligand Chiral Rhodium(II) Catalyst Enables the Enantioselective Total Synthesis of Piperarborenine B
A novel, mixed‐ligand chiral rhodium(II) catalyst, Rh2(S‐NTTL)3(dCPA), has enabled the first enantioselective total synthesis of the natural product piperarborenine B. A crystal structure of Rh2(S‐NTTL)3(dCPA) reveals a “chiral crown” conformation with a bulky dicyclohexylphenyl acetate ligand and three N‐naphthalimido groups oriented on the same face of the catalyst. The natural product was prepared on large scale using rhodium‐catalyzed bicyclobutanation/ copper‐catalyzed homoconjugate addition chemistry in the key step. The route proceeds in ten steps with an 8 % overall yield and 92 %
- NSF-PAR ID:
- 10236038
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 128
- Issue:
- 16
- ISSN:
- 0044-8249
- Page Range / eLocation ID:
- p. 5067-5071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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