Synthesis of a C-7 Pd-glycosyl-donor via the base promoted alkylative CO2 trapping with 2-acetylfuran

A practical one pot alkylative carboxylation of 2-acetylfuran was developed. The reaction was optimized for the synthesis of methyl β-ketoesters. The β-keto-ester product was used in the asymmetric synthesis of a C-7 pyranone precursor for a Pd-glycosylation reaction, with the goal of its use in the synthesis of pyran containing natural products, such as Aspergillide C.