SF3•Et2O catalyzed intramolecular cyclization of diethyl 2-(dialkoxyphosphorylethyny1)-2-arylaminomalonates to 3-phosphonylated indoles

The boron trifluoride diethyl etherate catalyzed intramolecular cyclization of diethyl 2-(dialkoxyphosphorylethynyl)-2-arylaminomalonates afforded a series of novel 3-phosphonylated indoles, diethyl 2[3-(dialkoxyphosphoryl)-1H-indol-2-yl]propanedioates. Decarboxylation of the latter compounds resulted in the formation of ethyl 2-13-(dialkoxyphosphory1)-1H-indo1-2-yljacetates. (C) 2017 Elsevier Ltd. All rights reserved.