913626-89-8Relevant academic research and scientific papers
Enantioselective rhodium-catalyzed [2+2+2] cycloaddition of alkenyl isocyanates and terminal alkynes: Application to the total synthesis of (+)-lasubine II
Yu, Robert T.,Rovis, Tomislav
, p. 12370 - 12371 (2006)
The use of TADDOL-based phosphoramidite ligands on rhodium allows for the incorporation of terminal alkynes in the [2+2+2] cycloaddition with alkenyl isocyanates. Terminal aliphatic alkynes provide bicyclic lactams, while the use of aryl alkynes provides complementary access to vinylogous amides. Product selectivity seems to be governed by a combination of electronics and sterics, with smaller and/or more electron-deficient substituents favoring lactam formation. The use of homologous alkenyl isocyanates leads to an expedient asymmetric total synthesis of the alkaloid lasubine II. Copyright
