Concise synthetic approaches for the Laurencia family: formal total syntheses of (±)-laurefucin and (±)-E- and (±)-Z-pinnatifidenyne.
Herein is presented a cohesive strategy to rapidly fashion diverse members of the lauroxocane family of natural products, leading to the shortest syntheses of any member to date. These efforts include racemic formal total syntheses of laurefucin and E- and Z-pinnatifidenyne as well as a facile preparation of the oxocene core of 3E-dehydrobromolaurefucin. The key elements of the design are novel diastereoselective ring-expanding bromoetherifications of tetrahydrofurans triggered by a unique bromonium source (BDSB, Et(2)SBr·SbBrCl(5)) and strategically positioned nucleophilic traps, where altering the identity and position of these traps affords diverse functionality on the eight-membered ring backbone. Its biogenetic relevance is also discussed in light of the range of substrates that successfully undergo this key rearrangement.
Department of Chemistry, Columbia University, Havemeyer Hall, 3000 Broadway, New York, New York 10027, USA. sas2197@columbia.edu
Scott A
SA
Snyder
Alexandria P
AP
Brucks
Daniel S
DS
Treitler
Ioana
I
Moga
D004988:Ethers, Cyclic / Q000138:chemical synthesis* / Q000737:chemistry; D005663:Furans / Q000138:chemical synthesis* / Q000737:chemistry; D044722:Laurencia / Q000737:chemistry*; D008968:Molecular Conformation; D013237:Stereoisomerism
C480362:3-pinnatifidenyne; D004988:Ethers, Cyclic; D005663:Furans; C017459:laurefucin