Enantio and diastereoselectivity of cyclohexanone monooxygenase catalyzed oxidation of 1,3-dithioacetals

• Published in: Tetrahedron: asymmetry Vol. 7; no. 2; pp. 565 - 570
• Main Authors: Colonna, Stefano, Gaggero, Nicoletta, Carrea, Giacomo, Pasta, Piero
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-02-1996
• ISSN: 0957-4166; 1362-511X
• DOI: 10.1016/0957-4166(96)00040-7

The asymmetric oxidation of 2-substituted dithianes, dithiolanes and oxathiolanes catalyzed by cyclohexanone monooxygenase (CMO) has been examined. The introduction of substituents at the C-2 causes a decrease of the e.e. with the exception of 2-benzoyl-1,3-dithiane monosulfoxide (90% e.e.). With 2-monosubstituted dithioacetals CMO yields preferentially or exclusively the
trans diastereoisomer. The binding of the 1,3-dithioacetals at the active site of the enzyme is not only controlled by the sterical hindrance of the substituents in position 2 but also by the configuration at C-2. The stereoselectivity of CMO has been compared with that reported for microsomal flavin and cytochrome P-450 monooxygenases.
The asymmetric oxidation of 2-substituted dithioacetals catalyzed by cyclohexanone monooxygenase (CMO) has been examined. The stereoselectivity of the process has been compared with that reported for FMO and cyt P-450.