Homochiral cyclopentane-based C1-symmetric P,P ligands C5H8(PPh2)(PR2) from C2-symmetric C5H8(PCl2)2
作者:Lutz Dahlenburg、Andreas Wühr
DOI:10.1016/j.tetlet.2003.10.071
日期:2003.12
Treatment of 1,2-trans-C5H8(PCl2)(2) with 1,2-C2H4(NHPr-i)(2) gave the C-2-symmetric perhydro-1,6,2,5-diazaphosphocine C5H8P(Cl)N(Pr-i)CH2}(2)-cyclo, which produced dissymmetric C5H8(PPh2)P[N(Pr-i)CH2](2)-cyclo} on further reaction with PhMgBr. Cleavage of the P-N bonds with gaseous HCl afforded C5H8(PPh2)(PCl2), which was converted to C5H8(PPh2)P(OPh)(2)}(2) by reaction with phenol. All chiral P,P derivatives were obtained as racemates as well as resolved (1R,2R)-and (1S,2S)-enantiomers. (C) 2003 Elsevier Ltd. All rights reserved.