Stereoselective addition reactions of diphenylphosphine to pyridyl and pyrimidylalkynes: chiral 1,2-diheteroaryl-1,2-bis(diphenylphosphino)ethanes and their Group 6 metal carbonyl complexes
作者:Jonathan L Bookham、Darren M Smithies
DOI:10.1016/s0022-328x(98)01078-x
日期:1999.4
parent diphosphine. At moderately elevated temperatures, nitrogen coordination of 2-pyridyl and 2-pyrimidyl groups occurred for tetracarbonyl complexes of meso- or erythro-stereochemistry, but not for complexes of rac- or threo-form, to yield corresponding fac-tricarbonyl complexes. At 162°C the complex cis-rac-(CO)4WP,P′-Ph2PCH(R)CH(R)PPh2} (R=R′=2-pyridyl) is converted quantitatively into fac-erythro-(CO)3WP
碱催化的二苯基膦加到二芳基乙炔RCCR'中(R = R'= 2-吡啶基1 ; R = R'= 3-吡啶基2 ; R = 2-吡啶基,R'= 3-吡啶基3 ; R =苯基,R'= 2-吡啶基4,3-吡啶基5,2-嘧啶基6)通式博士的产率的二膦2 PCH(R)CH(R')PPH 2与烯烃副产物博士一起2 PC(R )CHR'和HC(R)C(R')PPh 2在除1以外的所有情况下都为2。选择的P,P'配位的M(CO)4种复合物(M =钼,钨)的已制备的二膦和它们的1 H-,13给出了13 C -NMR和31 P-NMR数据。明确使用四羰基配合物的13个CO-NMR信号模式确定母体二膦的立体化学。在适度升高的温度,2-吡啶基和2-嘧啶基团的氮协调发生了的四羰络合物内消旋-或赤-立体化学,但不适合的络合物外消旋-或苏-形式,以产生对应的FAC三羰络合物。在162°C下,复杂的顺式-rac-(CO)4