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Upstream product

• 39952-43-7 lithium di-(p-tolyl)-phosphide 
• 69055-79-4 (+)-(2R,3R)-2,3-O-isopropylidene-2,3-dihydroxy-1,4-dichlorobutane 
• 1019-71-2 chlorodi-p-tolylphosphane 
• 37002-45-2 (4S,5S)-2,2-dimethyl-4,5-bis(p-toluenesulfonyloxymethyl)-1,3-dioxolan 
• 1380504-50-6 C₃₅H₄₀O₄P₂ 
• 2409-61-2 di(p-tolyl)phosphine oxide 
• 58342-57-7 (4R,5R)-trans-4,5-bis(iodomethyl)-2,2-dimethyl-1,3-dioxolane 

Relevant academic research and scientific papers

Enantioselective Rh-Catalyzed Hydroboration of Silyl Enol Ethers

The asymmetric hydroboration of alkenes has proven to be among the most powerful methods for the synthesis of chiral boron compounds. This protocol is well suitable for activated alkenes such as vinylarenes and alkenes bearing directing groups. However, the catalytic enantioselective hydroboration of O-substituted alkenes has remained unprecedented. Here we report a Rh-catalyzed enantioselective hydroboration of silyl enol ethers (SEEs) that utilizes two new chiral phosphine ligands we developed. This approach features mild reaction conditions and a broad substrate scope as well as excellent functional group tolerance, and enables highly efficient preparation of synthetically valuable chiral borylethers.

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.

Hydroformylation process

A process for the production of 4-hydroxybutyraldehyde is described. The process comprises reacting allyl alcohol with a mixture of carbon monoxide and hydrogen in the presence of a solvent and a catalyst system comprising a rhodium complex and a 2,3-O-isopropylidene-2,3-dihydroxy-1,4-bis[bis(3,5-di-n-alkylphenyl)phosphino]butane. The process gives high yield of 4-hydroxybutyraldehyde compared to 3-hydroxy-2-methylpropionaldehyde.

Einfluesse von in para-Position zum Phosphor eingefuehrten Substituenten in das Diop-System auf die optische Induktion bei der asymmetrischen Hydrierung von Acylaminoacrylsaeureethylester und (Z)-Acylamino-zimtsaeuremethylester mit kationischen Rhodium-(Diop-Derivat)-Komplexen. I

(R,R)-Diop was modified at the diphenylphosphino group by the introduction of substituents in para-position to the phosphorus atoms.The influence of the substituents on the optical induction was examined for the hydrogenation of ethyl α-acylaminoacrylate (AAEE) and (Z)-methyl α-acylaminocinnamate (AZME) with + BF4- as catalyst.For both substrates the substituents affected the optical induction markedly.The observed effects can be attributed to the electronical features, solvation and in special cases also to the size of the substituents.