87248-41-7

Upstream product

• 321-98-2 (1S,2R)-(+)-ephedrine 
• 644-97-3 Dichlorophenylphosphine 
• 6143-71-1 bis(dimethylamino)phenyl phosphine 

Downstream Products

• 116432-33-8 (-)-(2S,3R)-3,4-dimethyl-2,5-diphenyl-nitrobenzo<4,3-g>1,6-dioxa-4-aza-5-phospha (5-PV) spiro <4.4>nonane 
• 174511-99-0 (R)-(+)-[(O-methyl)methylphenylphosphinite]borane 
• 55739-59-8 (S,S)-1,1'-(1,2-ethanediyl)bis[1-(2-methoxyphenyl)-1-phenyl]phosphine oxide 
• 55739-58-7 (S(P),S(P))-1,2-bis[(o-anisyl)(phenyl)phosphino]ethane 
• 1485-88-7 (S_P)-(o-methoxyphenyl)(methyl)phenylphosphine 
• 20663-35-8 (S_p)-(2-methoxyphenyl)methylphenylphosphine oxide 
• 6389-79-3 (+)-(R)_p methyl methylphenylphosphinate 
• 87214-08-2 C₁₇H₂₁INOP 

Relevant academic research and scientific papers

P-chiral, monodentate ferrocenyl phosphines, novel ligands for asymmetric catalysis

Eight P-chiral monodentate ferrocenyl phosphines (1a-h) were prepared in high enantiomeric excess (>95% ee in most cases) by way of an ephedrine-based oxazaphospholidine borane complex. Primary alkyl, secondary alkyl, and substituted aromatic substituents were successfully introduced at the phosphorus center, along with ferrocenyl and phenyl groups, generating phosphines of the general structure FcP(Ph)(R) (Fc = ferrocenyl, R = aryl, alkyl). The synthetic route employed provides facile access to a previously undeveloped class of chiral monophosphines. These compounds were evaluated as ligands in asymmetric catalytic reductive coupling of alkynes and aldehydes and were found to provide the desired chiral allylic alcohols with good regioselectivity and ee in many cases and with complete (E)-selectivity (>98:2) in all cases.

Asymmetric synthesis of (S,S)-(+)-1,1′-bis-(methyl-phenyl-phosphino) ferrocene

The asymmetric synthesis of 1,1′-bis-(methyl-phenyl-phosphino) ferrocene 1 is described using the oxazaphospholidine borane complex 5 as synthon. Two strategies were investigated, based either on P-C bond formation by ring opening of complex 5 with the 1,1′-dilithio ferrocene 10, or on homocoupling of the cyclopentadienyl-methyl-phenyl-phosphine borane 2 anion with FeCl2. The first leads to a diastereomeric mixture of the diphosphine 1 in a 55:45 ratio, and the low stereoselectivity is explained by the steric hindrance of the ferrocene dianion. In the second strategy, the (R)-cyclopentadienyl phosphine borane 2 (85% ee) was prepared by the reaction of CpNa with the optically active chlorophosphine borane 14, derived from the aminophosphine borane 6a. The coupling of 2 leads to the 1,1′-diphosphino ferrocene borane 13, which is obtained diastereomerically pure by recrystallization, then decomplexed to the corresponding (S,S)-diphosphine 1.