The elusive endo-product of the archetypal Diels-Alder reaction of furan and maleic anhydride – observed in the solid state at last

Key Points

• This research aims to elucidate the elusive endo-product of the Diels-Alder reaction between furan and maleic anhydride.
• Utilized solid-state analysis technique to observe the endo-product.
• Performed Diels-Alder reaction using furan and maleic anhydride.
• Assessed the results through various chemical characterization methods.
• The endo-product was successfully observed in the solid state, highlighting its stability.
• Demonstrated deviations from the Alder endo-rule, indicating unique reactivity patterns.
• Provided structural insights that could enhance understanding of Diels-Alder mechanisms.