of derivatives 4, 6a·Et2O, and 7a confirm a four-coordinate structure in which the metal center is in a distorted-tetrahedral geometry and the bulky heteroscorpionate ligands have a κ3 coordination mode. Interestingly, the alkyl-containing magnesium complexes 1–3 and 8a can act as highly efficient single-component initiators for the very rapid ring-opening polymerization of ε-caprolactone and lactides
空间位阻heteroscorpionate
锂乙脒[李(κ的反应3 -pbp吨
AMD)(THF)](PBP吨
AMD = Ñ,N' -diisopropylbis(3,5-二-叔-butylpyrazol -1-基)
乙脒基)和[李(κ 3 -
TBP吨
AMD)(THF)](
TBP吨
AMD = N-乙基- N' -叔-butylbis(3,5-二-叔-butylpyrazol -1-基)
乙脒基)被1个RMgCl的当量进行干净,得到相应的非手性单烷基
镁配合物的非常高的产率[Mg的(R)(κ 3 -NNN)](NNN = PBP吨
AMD,R =我(1),Et(2),CH 2 SiMe 3(3),CH 2 Ph(4),C 3 H 5(5);NNN =
TBP t
AMd,R = Me(6),Et(7),CH 2 SiMe 3(8),CH 2 Ph(9),C 3 H 5(10))。或者,这些单烷基
镁配合物可以通过将相应的二烷基
镁试剂R