The aza-Diels–Alder reaction protocol—a useful approach to chiral, sterically constrained α-amino acid derivatives

Different types of polycyclic α-amino acid derivatives are prepared from chiral imines by using well-established aza-Diels–Alder reaction conditions. Simply by varying the diene moiety, different products such as spirocyclic compounds 8 and 9, anthracene 10, and tetrahydroquinolines 15–21 are formed.