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Catalytic synthesis and transformations of organophosphorus compounds

“…Note that the enantiomeric purity was as high as 95% for the P-analogue of Naproxen. 62,63 Although the Rh-catalysed reduction of α-amino-and α-benzyloxyvinylphosphonates involving chiral ligands with an asymmetric centre on the phosphorus atom (Imamoto ligands) gave excellent results and the corresponding α-aminoand α-hydroxyphosphonates can be synthesised with high enantiomeric purity, this reaction is limited to compounds capable of enolisation, i.e., it is not applicable to aryl (or trifluoromethyl) derivatives (Scheme 27). 64 We tried to carry out the asymmetric reduction of α-aryliminophosphonates and α-aryloxophosphonates using chiral rhodium complexes.…”

Iridium catalysis: application of asymmetric reductive hydrogenation

“…37 The asymmetric hydrogenation of trifluoromethylated alkenes has 30 been attempted with (R)-BINAP-Ru catalysts with results varying from racemic to 83% ee. 32 Similarly, rhodium catalysis was used in conjunction with (R,R)DiPAMP or (S,S) Chiraphos, though results remained capped at 77% ee. 38 As can be seen in Table 4, from results obtained in the Andersson group, 39 the 35 hydrogenation of these substrates was achieved with very high conversion and ees (up to 96%).…”

“…31 Organophosphorous compounds can be employed for a great variety of uses including ligands for catalysis and drugs. 32 Since their use is mostly in chiral molecules, it is of vital importance to produce them in an optically pure form. Cheruku et al reported these hydrogenations in excellent conversion and ees for a variety of terminal substrates (Table 3).…”

Synthesis of 1-hetarylethylphosphonates

“…1-Arylethylphosphonates are cyclooxygenase inhibitors [1], Ca 2+ antagonists [2,3], neuroprotectors [3], psychotropic [3] and negative inotropic agents [2], and reactive immunization haptens [4,5]. These compounds may be regarded as phosphorus-containing structural analogs of 2-arylpropionic acids that are widely used in modern medical practice as nonsteroidal analgesic, antiphlogistic, and antipyretic drugs; examples are ibuprofen, naproxen, ketoprofen, flurbiprofen, tiaprofen, etc.…”