Alkyleisen‐ und Alkylcobalt‐Reagenzien, IV[1] Aldehydselektive Cyanoalkylierungen mit Cyanoalkyl‐Derivaten von Eisen(II) und anderen Übergangsmetallen

Alkyliron and Alkylcobalt Reagents, IV [1] . – Aldehyde‐Selective Cyanoalkylation with Cyanoalkyl Derivatives of Iron(II) and Other Transition Metals For the transfer of the cyanomethyl residue with high aldehyde vs. ketone selectivity, the Fe reagent 3 a is a good alternative to the known Ti reagent 1a [2] , whereas analogous reagents with the metals Mn, Co, Ni or Cu are unfavorable. For the aldehyde‐ vs. ketone‐selective transfer of the branched residues 1‐cyanoethyl and cyanoisopropyl, the Fe reagents 3b and 3c are distinctly better than the Ti reagents 1b and 1c .