A Convergent Synthesis of Enantiopure Open-Chain, Cyclic, and Fluorinated α-Amino Acids
作者:Shi-Guang Li、Fernando Portela-Cubillo、Samir Z. Zard
DOI:10.1021/acs.orglett.6b00656
日期:2016.4.15
A radical based synthesis of a broad variety of protected enantiopure α-amino acids, including fluorinatedderivatives, is described. The radicaladdition furnishes naturally latent mercapto-α-amino acids ideally equipped for native chemical ligation.
Adducts from the radical addition of xanthates to ethyl vinyl sulfide readily undergo elimination of the xanthate group upon thermolysis to give vinylic and/or allylic sulfides, depending on the structure. In the case of α-xanthyl ketones, the adducts are converted into α-keto vinyl carbinols by rearrangement of the sulfoxides derived from the vinylic and allylic sulfides.
作者:Béatrice Quiclet-Sire、Guillaume Revol、Samir Z. Zard
DOI:10.1021/ol9010294
日期:2009.7.2
A route to biaryl-3-carboxylate esters involving a radical 1,2-aryl migration has been developed. This strategy hinges on the radical addition of xanthate 2 to olefin 1 causing a 1,2-aryl shift leading to alpha,beta-unsaturated ester 5, which is then converted into biaryl 10 by treatment with DBU under microwave heating.