Metal catalyzed tandem Diels–Alder/hydrolysis reactions of 2-boron-substituted 1,3-dienes

2-Boron substituted 1,3-dienes have been prepared and used in experiments to demonstrate that it is possible to effect metal catalyzed Diels–Alder/hydrolysis tandem reactions. The boron substituted dienes are treated with dienophiles in toluene:alcohol solutions with rhodium or copper salt catalysts and heated to effect Diels–Alder reactions of the boron substituted dienes followed by hydrolysis of the boron-carbon bond in the Diels–Alder cycloadducts.

The graphical abstract shows the 2 Diels–Alder/hydrolysis reaction sequences that were investigated in the most detail.Figure optionsDownload as PowerPoint slideHighlights
► Highly organic solvent soluble 2-boron substituted 1,3-dienes have been prepared.
► These boron substituted dienes participate in Diels–Alder/hydrolysis reactions.
► Diels–Alder/hydrolysis reactions appear to be Lewis acid catalyzed reactions.