The Bradsher cycloaddition reaction, also known as the Bradsher cyclization reaction is a form of the Diels–Alder reaction which involves the [4+2] addition of a common dienophile with a cationic aromatic azadiene such as acridizinium or isoquinolinium.
The Bradsher cycloaddition was first reported by C. K. Bradsher and T. W. G. Solomons in 1958. [1] [2] [3]