Acyclic α-amino vinylphosphonates were alkylated through the Mitsunobu reaction then diolefinic compounds hence formed were subjected to RCM. Studies on the scope and limitations of RCM with these sterically hindered α-amino vinylphosphonates are detailed.
α-Aminovinylphosphonates were prepared by chemo- and stereoselective reduction of α-aminoallenephosphonates. Our results showed that the substituents on the allene, phosphonate, and nitrogen moieties affected the stereoselectivity of the reduction. Z-α-Amino vinylphosphonates were prepared with good selectivities up to > 95:5.
Spirodienone lactams were prepared from the oxidation of α-amino allenylphosphonates or ynamido-phosphonates. The limitations observed for this synthesis were addressed by changing the nature of phosphorylated moiety.
Regioselective Synthesis of Highly Substituted Imidazoles via the Sequential Reaction of Allenyl Sulfonamides and Amines
作者:Lian Yu、Yuan Deng、Jian Cao
DOI:10.1021/acs.joc.5b00141
日期:2015.5.1
A novel synthesis of imidazoles from electron-withdrawing group-substituted allenyl sulfonamides with amines was developed. The 4- and 5-functionalized imidazoles were constructed regioselectively, which depended on the substituents on the nitrogen atoms.