De novo synthetic design for air-stable bis primary phosphines: Synthetic,catalytic and biomedical motifs

The syntheses of a series of 'hitherto unknown' air-stable functionalized b isprimary phosphines are described. Elegant syntheses of bisprimary phosphi nes with P2N2 (20) and P2S2 (24) frameworks were achieved by using 3-aminop ropyl phosphine 3 and 3-bromopropyl phosphine 23 as building blocks. The hi ghlights of these synthetic approaches involve the user-friendly synthons 3 -aminopropyl phosphine 3 and 3-bromoproyl phosphine 23 and also the chemose lectivity in the aminolysis of acid ester 19 with 3-aminopropylphosphine 3, Ultimately, the first ever crystal structure of amido functionalized bispr imary phosphine is also reported. The successful conjugation of P2N2COOH 20 and P2S2COOH 24 to the peptides without oxidizing -PH2 groups further demo nstrated the stability and usefulness of compounds 20 and 24 in potential c atalytic and biomedical applications.