[EN] CATALYTIC ASYMMETRIC SYNTHESIS OF OPTICALLY ACTIVE alpha-HALO-CARBONYL COMPOUNDS [FR] SYNTHESE ASYMETRIQUE CATALYTIQUE DE COMPOSES DE DOLLAR G(A)-HALO-CARBONYLE OPTIQUEMENT ACTIFS
A New, Short, and Stereocontrolled Synthesis of <i>C</i><sub>2</sub>-Symmetric 1,2-Diamines
作者:Rajender Vemula、Nathan C. Wilde、Rajendar Goreti、E. J. Corey
DOI:10.1021/acs.orglett.7b01768
日期:2017.7.21
reaction of ammonia, glyoxal hydrate, and cyclohexanone. It is a very useful precursor for the diastereocontrolled synthesis of many C2-symmetric 1,2-diamines, a class which is important for the generation of a variety of C2-symmetric reagents and catalysts for enantioselective synthesis.
Modular ligands in asymmetric synthesis. Copper-mediated cyclopropanation
作者:Dora Tepfenhart、Lionel Moisan、Peter I. Dalko、Janine Cossy
DOI:10.1016/j.tetlet.2003.12.061
日期:2004.2
mediates asymmetric intermolecular cyclopropanations. Complexes derived from (R,R)- or (S,S)-1,1-diphenylethylenediamine, cyclic ketones, and Cu(I) or Cu(II) triflates were compared. The reactionbetween (−)-menthyl diazoacetate and 1,1-diphenylethylene affords cyclopropane carboxylates in up to 80% yield and with up to 78% de.
A library of star-shaped 2H-imidazolines has been synthesized via Debus Radziszewski condensation from 1,2-diketones and ketone starting materials. Selective reduction of one imine group of the 2H-imidazole intermediate with LiAlH4 or catalytic flow hydrogenation furnished 2H-imidazolines, which could be conveniently diversified by reacting the amine N with electrophiles, resulting in a set of 21 amide-, carbamate-, urea-, and allylamine-containing products. In total, five points of diversification could be used, which allow the production of a set of functionally diverse compounds. The synthesis of acylated 2H-imidazolidines resulted in intrinsically labile compounds, which spontaneously degraded to acyclic derivatives, as shown for the reaction of 2H-imidazolidine with hexylisocyanate.
Convenient routes to symmetrical benzils and chiral 1,2-diaryl-1,2-diaminoethanes, useful controllers and probes for enantioselective synthesis
作者:E.J. Corey、Duck-Hyung Lee、Sepehr Sarshar
DOI:10.1016/0957-4166(94)00336-a
日期:1995.1
Pathways for the diastereoselective preparation of chiral 1,2-diaryl-1,2-diaminoethanes from ArCOOH, ArCHO or ArBr are described.