147127-50-2

Upstream product

• 174511-99-0 (R)-(+)-[(O-methyl)methylphenylphosphinite]borane 

Downstream Products

• 351026-56-7 ((C₆H₅)(CH₃O)PCH₂CH₂P(OCH₃)(C₆H₅))2Rh₂Cl₂ 
• 17325-53-0 (R,R)-(-)-1,2-bis(methylphenylphosphino)ethane 
• 1020091-66-0 C₁₆H₂₆B₂P₂ 
• 97764-56-2 (S_P,S_P)-1,2-bis[(o-anisyl)(phenyl)phosphino-P-borane]ethane 
• 1155311-90-2 (S(P),S(P))-1,2-bis[(2,4-dimethoxyphenyl)(phenyl)phosphino-P-borane]ethane 
• 169437-76-7 (S_P,S_P)-1,2-bis[(methyl)(phenyl)phosphino-P-borane]ethane 

Relevant academic research and scientific papers

Enantiodivergent synthesis of P-chirogenic phosphines

Several approaches for the enantiodivergent synthesis of P-chirogenic mono- and diphosphines are described, using ephedrine methodology and phosphine borane chemistry. Firstly, both enantiomers of a tertiary phosphine can be obtained starting from the same oxazaphospholidine borane complex, prepared from (+)-ephedrine, when changing the order of addition of the organolithium reagents during the synthetic pathway. The second approach is based on the chlorophosphine boranes, which react with an organolithium reagent, to afford the corresponding phosphines with inversion of configuration. In the case where the chlorophosphine borane reacts with the t-butyl lithium reagent, a metal-halogen exchange occurs to afford the corresponding phosphide borane with retention of the configuration. The reaction of the phosphide borane with an alkyl halide leads to the same phosphine, but with the opposite configuration. Another approach depends on the diastereoselective preparation of the starting oxazaphospholidine borane complex from (-)-ephedrine, which leads according the case, to either one or the other enantiomer of a phosphine. Finally, the synthesis of (R,R)- and (S,S)-1,2-bis(methylphenylphosphino)ethane is also demonstrated using both enantiomers of the P-chirogenic diphosphinite diborane, which simultaneously allows the introduction of alkyl- or aryl substituents on the phosphorus atoms. In summary, these approaches show the great efficiency of the "ephedrine methodology" for the enantiodivergent synthesis of P-chirogenic mono- and diphosphines, and bearing alkyl or aryl substituents.

Direct use of chiral or achiral organophosphorus boranes as pro-ligands for transition metal catalyzed reactions

Chiral or achiral organophosphorus borane complexes were used without isolation of the free tricoordinate P(III) ligand; thus, the borane adducts could be used either directly with metal salts to perform the catalysis, or they could be decomplexed by DABCO, or cyclooctadiene, and used in situ to generate the catalytic species. Chiral copper, palladium and rhodium complexes prepared using this method, were tested in asymmetric organometallic catalyzed 1,4-addition to 2-cyclohexenone, allylation of Schiff base and hydrogenation of α-acetamidocinnamic acid derivatives, respectively.