Organocatalysis for the Asymmetric Michael Addition of Cycloketones and ?, ?-Unsaturated Nitroalkenes
نویسندگان
چکیده
Michael addition is one of the most important carbon–carbon bond formation reactions. In this study, an (R, R)-1,2-diphenylethylenediamine (DPEN)-based thiourea organocatalyst was applied to asymmetric nitroalkenes and cycloketones produce a chiral product. The primary amine moiety in DPEN reacts with ketone form enamine activated through hydrogen between nitro group ?, ?-unsaturated nitroalkene thiourea. Here, aim obtain product 1,4-addition alkene new bond. As result, diamine converted into enamine. reaction proceeded relatively high level enantioselectivity achieved using double activation bonding products levels (76–99% syn ee) diastereoselectivity (syn/anti = 9/1) were obtained yields range 88–99% depending on ketone.
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ژورنال
عنوان ژورنال: Catalysts
سال: 2021
ISSN: ['2073-4344']
DOI: https://doi.org/10.3390/catal11081004