17299-04-6

Upstream product

• 2935-44-6 hexane-2,5-diol 
• 98-59-9 p-toluenesulfonyl chloride 
• 34338-96-0 (2S,5S)-2,5-hexanediol 

Downstream Products

• 216019-41-9 (2R,5R)-(+)-2,5-bis-(diphenylphosphino)hexane 
• 929684-94-6 1-(2-bromo-phenyl)-2,5-dimethyl-cyclopentanecarbonitrile 

Relevant academic research and scientific papers

Synthesis, determination of enantiomeric purity and structural characterisation of enantiopure (2R,5R)-(+)-2,5-bis-(diphenylphosphino)-hexane, a chiral DPPB analogue

Enantiopure (2R,5R)-(+)-2,5-bis-(diphenylphosphino)hexane, 3, a chiral analogue of 1,4-bis-(diphenylphosphino)butane was synthesized in two steps from enantiomerically pure (2S,5S)-(+)-hexanediol. The molecular structure of (2R,5R)-3 was determined by X-ray structure analysis of its nickel-(II)-complex showing a rare dimeric species; NMR analysis of the reaction product of 3 with (+)-di-μ-chloro-bis-{2-[1-(dimethylamino)ethyl]phenyl-C,N}-dipallad ium allowed to deduce the enantiomeric purity.

Stereochemical investigations reveal the mechanism of the bacterial activation of n-alkanes without oxygen

Anaerobic growth of the bacterium strain HxN1 with n-hexane gives nearly equal amounts of (2R,1 R)- and (2S,1 R)-(1-methylpentyl)succinate, which are formed by the radical addition of the hydrocarbon to fumarate (see scheme). The highly selective attack on the pro-S hydrogen atom at C2 of n-hexane is associated with inversion of the configuration at C2 during binding to fumarate and exhibits isotopic discrimination against a C-2H bond. Copyright

A new class of versatile chiral-bridged atropisomeric diphosphine ligands: Remarkably efficient ligand syntheses and their applications in highly enantioselective hydrogenation reactions

A series of chiral diphosphine ligands denoted as PQ-Phos was prepared by atropdiastereoselective Ullmann coupling and ring-closure reactions. The Ullmann coupling reaction of the biaryl diphosphine dioxides is featured by highly efficient central-to-axial chirality transfer with diastereomeric excess >99%. This substrate-directed diastereomeric biaryl coupling reaction is unprecedented for the preparation of chiral diphosphine dioxides, and our method precludes the tedious resolution procedures usually required for preparing enantiomerically pure diphosphine ligands. The effect of chiral recognition was also revealed in a relevant asymmetric ring-closure reaction. The chiral tether bridging the two aryl units creates a conformationally rigid scaffold essential for enantiofacial differentiation; fine-tuning of the ligand scaffold (e.g., dihedral angles) can be achieved by varying the chain length of the chiral tether. The enantiomerically pure Ru- and Ir-PQ-Phos complexes have been prepared and applied to the catalytic enantioselective hydrogenations of α- and β-ketoesters (C=O bond reduction), 2-(6′-methoxy- 2′-naphthyl)-propenoic acid, alkyl-substituted β-dehydroamino acids (C=C bond reduction), and N-heteroaromatic compounds (C=N bond reduction). An excellent level of enantioselection (up to 99.9% ee) has been attained for the catalytic reactions. In addition, the significant ligand dihedral angle effects on the Ir-catalyzed asymmetric hydrogenation of N-heteroaromatic compounds were also revealed.

An Efficient Procedure for the Synthesis of C-Chiral Bisphosphines.

A practical method for the synthesis of bisphosphines containing homochiral carbon backbones is described.This procedure entails sequential reaction of a homochiral ditosylate with the appropriate dialkyl- or diarylphosphine-borane anion followed by BH3 decomplexation mediated by HBF4*OMe2.