Furan-2-boronic acid → Methyl 4-(3-(furan-2-yl)benzyl)-1,4,5,6-tetrahydrocyclopenta[b]pyrrole-2-carboxylate

Participants

Reaction Steps

The title compound was synthesized in four steps. First, tosyl protected methyl 4-oxo-1,4,5,6-tetrahydrocyclopenta[b]pyrrole-2-carboxylate (methyl 4-oxo-1-tosyl-1,4,5,6-tetrahydrocyclopenta[b]pyrrole-2-carboxylate) (1.50 g, 8.37 mmol) was reacted with 3-bromobenzylmagnesium bromide (15 mL, 3.75 mmol) according to General Procedure 3 to give exo olefin-containing compound (E)-methyl 4-(3-bromobenzylidene)-1-tosyl-1,4,5,6-tetrahydrocyclopenta[b]pyrrole-2-carboxylate, followed by coupling with furan-2-boronic acid (0.138 g, 1.23 mmol) according to General Procedure 9.1 to give (E)-methyl 4-(3-(furan-2-yl)benzylidene)-1-tosyl-1,4,5,6-tetrahydrocyclopenta[b]pyrrole-2-carboxylate, then tosyl deprotection according to General Procedure 10.1 to give (E)-methyl 4-(3-(furan-2-yl)benzylidene)-1,4,5,6-tetrahydrocyclopenta[b]pyrrole-2-carboxylate. Hydrogenation of (E)-methyl 4-(3-(furan-2-yl)benzylidene)-1,4,5,6-tetrahydrocyclopenta[b]pyrrole-2-carboxylate according to General Procedure 6, then purification by column (Isco CombiFlash) eluting with a gradient of 0-25% EtOAc/heptane afforded the title compound: 0.024 g.

Provenance & Evidence