320718-10-3

Upstream product

• 320718-06-7 N-allyl-N-((1S,5R)-5-[tert-butyldimethylsilanyloxy)cyclopent-2-enyl]-4-methylbenzenesulfonamide 
• 29783-26-4 cis-4-cyclopentene-1,3-diol 
• 4083-64-1 Tosyl isocyanate 
• 138604-24-7 (3aS,6aR)-3-(toluene-4-sulfonyl)-3,3a,6,6a-tetrahydrocyclopent-4-enoxazol-2-one 
• 143668-59-1 N-((1S,5R)-5-hydroxycyclopent-2-enyl)-4-methylbenzenesulfonamide 
• 158361-26-3 N,N′-ditosyl-meso-cyclopent-4-ene-1,3-diol biscarbamate 
• 441768-85-0 N-allyl-N-((1S,5R)-5-hydroxycyclopent-2-enyl)-4-methylbenzenesulfonamide 

Downstream Products

• 72741-87-8 swainsonine 
• 441768-86-1 (R)-4-(tert-butyldimethylsilanyloxy)-4-[(S)-1-(toluene-4-sulfonyl)-2,5-dihydro-1H-pyrrol-2-yl]butan-1-ol 

Relevant academic research and scientific papers

A new approach to (-)-swainsonine by ruthenium-catalyzed ring rearrangement

A new enantioselective synthesis of the idolizidine alkaloid (-)-swainsonine 1 in 40% overall yield starting from the known oxazolidinone 6 is described. Throughout the synthesis, the high efficiency of metal-catalyzed reactions is illustrated. The key step is a new ruthenium-catalyzed metathesis rearrangement reaction. In this ring-closing/ring-opening tandem process, stereocenters are transferred from a ring to the olefinic side chain of the formed heterocycle. The metathesis precursor was obtained by palladium-catalyzed desymmetrization of cyclopentenediol. The synthesis was completed by functionalization of the terminal double bond, cyclization of the second ring, and diastereoselective dihydroxylation.

Synthesis and application of a permanently immobilized olefin-metathesis catalyst

Immobilized on Merrifield polystyrene, catalyst 1 shows high activity and stability in different types of olefin metathesis. The products can be isolated in high purity by simple filtration, while the immobilized catalyst 1 can be recycled and used up to four times in the ring-closing metathesis of 2. Mes = methane sulfonate, Ts = toluene sulfonate, Cy = cyclohexyl.