Asymmetric transformation (deracemisation) of an atropisomeric bisheterocyclic amine†

Abstract

Heating (±)-6,8,14,17-tetrahydro-7H-[1,2,5]triazepino[3,2-b∶7,1-b′]diquinazoline-14,17-dione 1 with (+)-CSA gives (–)-1 with >90% ee via a crystallisation-induced asymmetric transformation, the first non-racemic example of a C₂ symmetric bisheterocycle which is atropisomeric by virtue of retarded rotation around an N–N bond.

References

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