114444-90-5

Upstream product

• 100-42-5 styrene 
• 931-48-6 2-cyclohexylacetylene 
• 1221066-13-2 C₁₃H₁₅Cl₂NO₂S 
• 69052-20-6 E-cinnamyltriphenylphosphonium chloride 
• 91861-48-2 Tributyl-((E)-3-phenyl-allyl)-phosphonium; bromide 
• 2043-61-0 cyclohexanecarbaldehyde 
• 38633-40-8 (E)-cinnamyltriphenylphosphonium bromide 

Relevant academic research and scientific papers

Ruthenium-catalyzed coupling of unactivated olefins with unactivated alkynes

A new ruthenium-catalyzed coupling reaction of an olefin with an alkyne is presented. The C-H bond of the olefin formally undergoes trans addition to the C-C triple bond to produce conjugated dienes.

A highly tunable stereoselective olefination of semistabilized triphenylphosphonium ylides with N -Sulfonyl imines

The Wittig reaction involving direct olefination of triphenylphosphonium ylides (Ph3PCHR) with aldehydes is arguably the most often used method for alkene synthesis, but in general it yields mixtures of Z- and E-alkenes for semistabilized triphenylphosphonium ylides (R = aryl or vinyl). We have developed a simple and efficient protocol to improve the stereoselectivity significantly by replacing the aldehydes used in the Wittig reaction with N-sulfonyl imines, which possess distinct electronic and steric properties relative to aldehydes. A broad range of aromatic, α,β-unsaturated, and aliphatic imines bearing appropriate N-sulfonyl groups smoothly undergo olefination reaction with various benzylidenetriphenylphosphoranes or allylidenetriphenylphosphoranes under mild reaction conditions to afford an array of both Z- and E-isomers of conjugated alkenes in good to excellent yields and with greater than 99:1 stereoselectivity. Moreover, this tunable protocol has been successfully applied to the highly stereoselective synthesis of two anticancer agents, DMU-212 and its Z-isomer.

Stereoselective E and Z Olefin Formation by Wittig Olefination of Aldehydes with Allylic Phosphorus Ylides. Stereochemistry

Sterically crowded allylic tributylphosphorus ylides such as β-γ-disubstituted allylic ylides react with various aldehydes to afford E olefins with high stereoselectivity (E>92percent).As the steric demand of the ylides was decreased, bulky aldehydes were required to achieve high E selectivity.On the other hand, predominant or exclusive formation of Z olefins was achieved by using allylic triphenylphosphorus ylides and tertiary aldehydes like pivaldehyde, while the combination of allylic triphenylphosphorus ylides and such large secondary aldehydes as cyclohexanecarboxaldehyde led to E olefin formation under the lithium salt free conditions.The distinct lithium salt effect was observed in the reaction effected with triphenylphosphorus ylides.The origin of the observed E or Z selectivity can be reasonably explained according to Vedejs' rationale on the Wittig reaction stereochemistry.