The use of vinyl electrophiles in synthesis has been hampered by the lack of access to a suitable reagent that is practical and of appropriate reactivity. In this work we introduce a vinyl thianthrenium salt as an effective vinylating reagent. The bench-stable, crystalline reagent can be readily prepared from ethylene gas at atmospheric pressure in one step and is broadly useful in the annulation chemistry
Synthesis of Enantiopure Tertiary Skipped Diynes via One-Pot Desymmetrizing TMS-Cleavage
作者:Malek Nechab、Nicolas Vanthuyne
DOI:10.1021/ol3017462
日期:2012.8.3
Enantiopure tetrasubstitutedskippeddiynes were readily synthesized from N-protected amino esters upon addition of lithium TMS-acetylide which was found to be desymmetrizing through one-pot selective TMS-cleavage. The deprotection of the TMS group was realized through a one-pot silicon atom attack by the liberated methoxide, which was diastereoselective due to a conformational favorable chelate.
peculiar 3D orientation of these substituents is able to reproduce the hydrophobic side chains in LxxLL-like proteinrecognitionmotifs. Biological results showed altered p53 expression and nuclear translocation in cells sensitive to the compounds, suggesting p53 involvement in their anticancer mechanism of action. Unfortunately, because of poor solubility of the active analogues, it was not possible
Asymmetric Synthesis of β
<sup>2</sup>
‐Aryl Amino Acids through Pd‐Catalyzed Enantiospecific and Regioselective Ring‐Opening Suzuki–Miyaura Arylation of Aziridine‐2‐carboxylates
作者:Youhei Takeda、Tetsuya Matsuno、Akhilesh K. Sharma、W. M. C. Sameera、Satoshi Minakata
DOI:10.1002/chem.201902009
日期:2019.8
A Pd‐catalyzed enantiospecific and regioselective ring‐opening Suzuki–Miyaura arylation of aziridine‐2‐carboxylates was developed. The cross‐coupling allows for the asymmetric preparation of enantioenriched β2‐aryl amino acids, starting from commercially available enantiopure d‐ and l‐serine esters. The mechanism and selectivity of the reaction was rationalized based on computational models.