Cu-catalyzed selective mono-n-heteroarylation of chiral diamines & asymmetric conjugate addition of dibenzoylmethane to trans-beta-nitrostyrene

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2013
Ünver, Muhammet Yağız
In the first part of the thesis, a new methodology has been developed to desymmetrize trans-(R,R)-cyclohexane-1,2-diamine, a C2-symmetrical most demanding chiral backbone, by using copper chemistry (modified Ullman). Various halo substituted nitrogen heteroaromatic compounds were selectively introduced to one of the diamine unit. 10 novel coupling products were synthesized in a single step procedure. These resultant coupling products have amidine motifs which can be valuable candidates as a basic catalophoric part in the context of bifunctional organocatalyst. The second part of the thesis comprises the asymmetric organocatalytic Michael addition of dibenzoylmethane to various β-nitroolefins. 2-AminoDMAP/Squaramide type bifunctional acid/base organocatalyst, developed in our research group, has been used under optimized condition with very low catalyst loading and short reaction duration. Enantioselectivities of 14 chiral Michael addition products are varied between 80-98% ee.