Asymmetric amination of tetralone and chromanone derivatives employing ω‑transaminases
Various (S)-selective and (R)-selective ω-transaminases were investigated for the amination of 1- and 2-tetralone and derivatives as well as of 3- and 4-chromanone. All ketones tested were aminated to give the corresponding enantiopure amines (ee > 99%) employing at least one of the enzymes investigated. In most of the cases the (S)- as well as the (R)-enantiomer was obtained in optically pure form. The amination of 3-chromanone was performed on a 100 mg scale leading to optically pure (R)-3-aminochromane (ee > 99%) with complete conversion and 78% isolated yield.