Chiral 2-aminodmap/sulfonamides and squaramides as bifunctional acid/base organocatalysts in asymmetric catalysis

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2011
Işık, Murat
Synthesis and evaluation of catalytic performances of novel bifunctional 2- aminoDMAP-Thiourea/ Sulfonamide/ Squaramide organocatalysts derived from trans-(R,R)-cyclohexane-1,2-diamine forms the main goal of this thesis. For this purpose, direct selective mono-N-pyridilization of trans-(R,R)-cyclohexane-1,2- diamine via Pd and Cu catalysis is described successfully first. Facile preparation of chiral 2-aminoDMAP core catalaphore led to the development of various 2- aminoDMAP- Thiourea/ Sulfonamides/ Squaramides as bifunctional acid/base organocatalyst libraries (most in two-steps overall) which showed good results in asymmetric conjugate addition of 1,3-dicarbonyls to trans-(β)-nitrostyrene. Enantiomeric excesses (ee) up to 93% were attained.

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Citation Formats
M. Işık, “Chiral 2-aminodmap/sulfonamides and squaramides as bifunctional acid/base organocatalysts in asymmetric catalysis,” Ph.D. - Doctoral Program, Middle East Technical University, 2011.