Total Synthesis and Establishment of the Stereochemistry of Spiniferin-1, a Rare Planar Chiral Marine Natural Product with a 1,6-Methano[10]annulene Skeleton

Abstract

Spiniferin-1, a rare planar chiral natural product with a 1,6-methano[10]annulene skeleton, has been synthesized via a novel polyfluoroalkanosulfonyl fluoride induced cascade carbocation rearrangement reaction. Natural spiniferin-1 was established as a racemic mixture by comparing its specific rotation with those of our synthesized S p -(+)-spiniferin-1 and its R p -(-)-enantiomer.

Good Partnership between Sulfur and Fluorine: Sulfur-Based Fluorination and Fluoroalkylation Reagents for Organic Synthesis

“…Poly­(per)­fluoroalkanesulfonyl fluorides are capable of inducing rearrangement reactions . For example, using HCF 2 CF 2 OCF 2 CF 2 SO 2 F as the reagent, γ-hydroxymethyl cyclohexenone 23 has been transformed into cyclopropyl enone 24 in 82% yield via tandem carbonium rearrangement (Scheme )…”

Planar Chiral p,p′-Terphenyl-Based Cyclophanes with Remarkable Enantiomer Stability: Synthesis, Theoretical Investigations, and Complexation Studies

“…[n]­Cyclophanes, ( I , Chart ) also known as “ansa” compounds, [m,n]­cyclophanes ( II , Chart ) and trans -cycloalkenes ( III , Chart ) are well-known examples of compounds which, when properly substituted and/or having bridges of suitable lengths, can exhibit atropisomers due to their planar chirality. These are complemented by bridged annulenes such as the natural spiniferin ( IV , Chart ) and metallocenes (e.g., V , Chart ). In addition, pillar[5]­arenes ( VI , Chart ) were more recently reported to display planar chirality that in some cases can be inverted by achiral guest molecules …”