ABSTRACT
The total synthesis of (±)-aspergilline A (1) is described. Key features of the synthesis include pyrrolinone formation via reaction of an intermediate propargyl amine with a methyl malonyl chloride derived ammonium enolate and a formal [3+2] cycloaddition between an imidate and cyclopropenone.
ABSTRACT
A method for chemoselective carbonyl ylide formation utilizing the Rh(II) catalyzed decomposition of electronically differentiated diazo malonates is disclosed. Treatment of ethyl, trifluoro ethyl diazo malonate with a Rh(II) catalyst selectively forms a carbonyl ylide from the relatively electron rich ethyl ester. This carbonyl ylide can be trapped by various alkynes giving highly functionalized oxabicyclic compounds in a chemo-, regio-, and diastereoselective fashion.
Subject(s)
Alkynes/chemistry , Malonates/chemistry , Catalysis , Cyclization , Esters , Molecular Structure , Rhodium/chemistry , StereoisomerismABSTRACT
Up for grabs: A modular receptor comprises a hexaazatriphenylene "platform" and three imide residues on its concave side carrying flexible alkane chains. The chains not only populate the host's cavity but can also extend and can grab an appropriately sized and shaped guest in solution.
