Abstract Nitromethyl, cyanomethyl, and phenylethynyl anions add selectively ortho to arenes containing electron-witdrawing groups and complexed with cyclopentadienyliron. Under similar reaction conditions anions such as alkyl, dichloromethyl and trichloromethyl add in a non-selective way. Addition of the trichloromethyl anion is thermodynamically controlled at extended reaction times and, due to the size of the anion, the meta addition product is ...
