57221-95-1

Upstream product

• 10177-78-3 di-(3-methylphenyl)-phosphine 
• 69055-79-4 (+)-(2R,3R)-2,3-O-isopropylidene-2,3-dihydroxy-1,4-dichlorobutane 
• 59779-75-8 diethyl (4R,5R)-2,2-dimethyl-1,3-dioxolane-4,5-dicarboxylate 
• 50622-09-8 2,3-O-isopropylidene-L-threitol 
• 13685-23-9 chloro-di-(3-methylphenyl)phosphine 
• 37002-45-2 (4S,5S)-2,2-dimethyl-4,5-bis(p-toluenesulfonyloxymethyl)-1,3-dioxolan 

Relevant academic research and scientific papers

Novel Copper Complexes of Chiral Diphosphines: Preparation, Structure, and Use To Form Rhodium Complex Catalysts for Chiral Hydrogenations

Treatment of chiral diphosphines 5a-c and 13 ("DIOP", aryl derivatives and related substances) with CuCl in boiling ethanol gave complexes having the composition n, 6a-c and 11.Crystallizations of 6a-c from crude 70-80percent pure 5a-c and decomposition of the complexes by ammonia gave the pure diphosphines.Ligand exchange between 6a-c and 2 in methanol at 23 deg C was rapid and complete.Treatment of the resulting solutions with H2 gave active catalysts for asymmetric hydrogenations.

Rhodium-Catalyzed Enantioselective Radical Addition of CX4 Reagents to Olefins

We describe the synthetically useful enantioselective addition of Br?CX3 (X=Cl or Br) to terminal olefins to introduce a trihalomethyl group and generate optically active secondary bromides. Computational and experimental evidence supports an asymmetric atom-transfer radical addition (ATRA) mechanism in which the stereodetermining step involves outer-sphere bromine abstraction from a [(bisphosphine)RhIIBrCl] complex by a benzylic radical intermediate. This mechanism appears unprecedented in asymmetric catalysis.