N‐Functionalized Ferrocenes: Subvalent Group XIV Element Chlorides and tert‐Butyllithium‐Induced C−C Bond Cleavage under Mild Conditions |
| |
Authors: | Dr Bastian Nayyar Dr Hazem Alnasr Prof?Dr Wolf Hiller Prof?Dr Klaus Jurkschat |
| |
Institution: | Fakult?t für Chemie und Chemische Biologie, Technische Universit?t Dortmund, Dortmund, Germany |
| |
Abstract: | The ferrocene derivative (η5‐Cp)Fe{η5‐C5H3‐1‐(ArNCH)‐2‐(CH2NMe2)} ( 1 ; Ar=2,6‐iPr2C6H3)) reacts diastereoselectively with LiR by carbolithiation and subsequent hydrolysis to give (η5‐Cp)Fe{η5‐C5H3‐1‐(ArHNCHR)‐2‐(CH2NMe2)} ( 3 : R=tBu; 4 : R=Ph; 5 : R=Me) in high yields. For R=tBu, the organolithium derivative (η5‐Cp)Fe{η5‐C5H3‐1‐(ArLiNCHR)‐2‐(CH2NMe2)} ( 2 ) was isolated. Compound 2 reacts with GeCl2?dioxane and SnCl2 to give the metallylene amide chlorides (η5‐Cp)Fe{η5‐C5H3‐1‐(ArMNCHtBu)‐2‐(CH2NMe2)} 6 (M=GeCl) and 7 (M=SnCl), respectively, which each contain three stereogenic centers. The potential of 7 as a ligand in transition‐metal chemistry is demonstrated by formation of its complex (η5‐Cp)Fe{η5‐C5H3‐1‐(ArMNCHtBu)‐2‐(CH2NMe2)} 9 , M= Sn(Cl)W(CO)5]. Treatment of 3 with tert‐butyllithium at room temperature causes an unprecedented carbon–carbon bond cleavage whereas under kinetic control, lithiation at the Cp‐3 position takes place, which leads to the isolation of (η5‐Cp)Fe{η5‐C5H3‐1‐(ArHNCHtBu)‐2‐(CH2NMe2)‐3‐SiMe3} ( 10 ). |
| |
Keywords: | C− C bond cleavage ferrocenes germanium lithium tin |
|
|