criterion is confirmed by X-ray analysis of IIIb. Exo-isomers, IIIb,c, were obtained by alkylation of the η6-fluorenylchromium tricarbonyl anion (I) with the corresponding halides RX in tetrahydrofuran (THF) at low temperature. Endo-isomers (Vb,c) have been obtained by alkylation of the η6-fluorenylchromium tricarbonyl anion (II) with subsequent thermal rearrangement of intermediate σ-organometal derivatives
一种方法,以确定的9-取代的
芴铬三羰基复合物的几何构型(η 6 -9-RC 13 ħ 9)的Cr(CO)3,其允许一个之间进行区分外型-异构体式(IIIa-e)和内-异构体(Va–e)被提议;a,R = CH 3;b,R = CH 2 HC 6 H 5,c,R = D;d,R = tC 4 H 9; n =1。e,R = C 6 H 5。此方法基于测量芳族溶剂从CDCl 3传递到C时在1 H NMR光谱中诱导的
化学位移6 D 6解决方案(ASIS效果)。该标准的有效性通过IIIb的X射线分析得以证实。外型-异构体,IIIb族,C,是由η的烷基化得到6 -fluorenylchromium三羰基阴离子(I)与相应的卤化物RX在
四氢呋喃(THF)在低温下。远藤-异构体(VB,C)已经由η的烷基化得到6与没有其隔离中间σ-有机
金属衍
生物(IV)的后续热重排-fluorenylchromium三羰