1387613-78-6Relevant articles and documents
Enantiomerically pure phosphaalkene-oxazolines (PhAk-Ox): Synthesis, scope and copolymerization with styrene
Dugal-Tessier, Julien,Serin, Spencer C.,Castillo-Contreras, Emmanuel B.,Conrad, Eamonn D.,Dake, Gregory R.,Gates, Derek P.
, p. 6349 - 6359 (2012/06/30)
The design of a synthetic route to a class of enantiomerically pure phosphaalkene-oxazolines (PhAk-Ox) is presented. The condensation of a lithium silylphosphide and a ketone (the phospha-Peterson reaction) was used as the P=C bond-forming step. Attempted condensation of PhC(=O)Ox (Ox=CNOCH(iPr)CH 2) and MesP(SiMe3)Li gave the unusual heterocycle (MesP)2C(Ph)=CN-(S)-CH(iPr)CH2O (3). However, PhAk-Ox (S,E)-MesP=C(Ph)CMe2Ox (1 a) was successfully prepared by treating MesP(SiMe3)Li with PhC(=O)CMe2Ox (52 %). To demonstrate the modularity and tunability of the phospha-Peterson synthesis several other phosphaalkene-oxazolines were prepared in an analogous manner to 1 a: TripP=C(Ph)CMe2Ox (1 b; Trip=2,4,6-triisopropylphenyl), 2-iPrC 6H4P=C(Ph)CMe2Ox (1 c), 2-tBuC 6H4P=C(Ph)CMe2Ox (1 d), MesP=C(4-MeOC 6H4)CMe2Ox (1 e), MesP=C(Ph)C(CH 2)4Ox (1 f), and MesP=C(3,5-(CF3) 2C6H3)C(CH2)4Ox (1 g). To evaluate the PhAk-Ox compounds as prospective precursors to chiral phosphine polymers, monomer 1 a and styrene were subjected to radical-initiated copolymerization conditions to afford [{MesPC(Ph)(CMe2Ox)} x{CH2CHPh}y]n (9 a: x=0.13n, y=0.87n; GPC: Mw=7400 g mol-1, PDI=1.15). Copyright
