Photochemically generated nitrilium phosphane-ylid tungsten complexes and their reactivity towards alkyne and nitrile derivatives
作者:Rainer Streubel、Hendrik Wilkens、Peter G. Jones
DOI:10.1039/a905752h
日期:——
The photochemically generated nitrilium phosphane-ylid tungsten complex 2 reacts with different activated alkynes, dimethyl acetylenedicarboxylate (DMAD) (i) and ethyl acetylenecarboxylate (ii), and nitriles, ethyl cyanoformate (ECF) (iii) and 1-piperidinonitrile (iv), giving [3+2] cycloaddition products such as the 2H-1,2-azaphosphole complexes 3 (i) and 4 (ii), the 2H-1,4,2-diazaphosphole complex 5 (iii) and the 2H-1,3,2-diazaphosphole complex 7 in good to excellent yields, the latter complexes, 4–7, being formed regioselectively; the structure of the first ester-functionalized 2H-1,4,2-diazaphosphole complex 5 was established by X-ray analysis.
光
化学产生的腈基
磷烷基
钨络合物2与不同的活化
炔烃、二
甲基乙炔二
羧酸酯(
DMAD)(i)和
乙炔羧酸乙酯(ii)以及腈类、
氰基甲酸乙酯(
ECF)(iii)和1-
哌啶腈(iv)反应,生成[3+2]环加成产物,如2H-1,2-
氮杂
磷杂
环戊烯络合物3(i)和4(ii)、2H-1,4,2-二
氮杂
磷杂
环戊烯络合物5(iii)和2H-1,3,2-二
氮杂
磷杂
环戊烯络合物7,产率良好至极佳,后几种络合物4-7是按位点选择性形成的;第一个
酯官能化的2H-1,4,2-二
氮杂
磷杂
环戊烯络合物5的结构通过X射线分析确定。