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Abstract An enantioselective synthesis of (−)‐10‐hydroxyacutuminine is reported. Central to our strategy is a photochemical [2+2] cycloaddition that forges two of the quaternary stereocenters present in the acutumine alkaloids. A subsequent retro‐aldol/Dieckmann sequence furnishes the spirocyclic cyclopentenone. Efforts to chlorinate the acutumine scaffold at C10 under heterolytic or radical deoxychlorination conditions led to the synthesis of an unexpected cyclopropane‐containing pentacycle.
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Lessons in Strain and Stability: Enantioselective Synthesis of (+)‐[5]‐Ladderanoic Acid
Abstract The synthesis of structurally complex and highly strained natural products provides unique challenges and unexpected opportunities for the development of new reactions and strategies. Herein, the synthesis of (+)‐[5]‐ladderanoic acid is reported. En route to the target, unusual and unexpected strain release driven transformations were uncovered. This occurrence required a drastic revision of the synthetic design that ultimately led to the development of a novel stepwise cyclobutane assembly by an allylboration/Zweifel olefination sequence.
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- Award ID(s):
- 1726633
- PAR ID:
- 10124455
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 59
- Issue:
- 1
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 436-441
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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