Carboxylate versus imidobenzoate bonding for anthranilic acid derivatives. Crystal structures of (W(#eta#-C_5Me_5)Cl_3(#eta#~2-O_2CC_6H_4NH_2-2)] and [ReCl(OEt)(PPh_3)_2(NC_6H_4CO_2)]

摘要

The paramagnetic complex [W(#eta#-C_5Me)5)Cl_3(#eta#_2-O_2CC_6H_4NH_2-2)] (1) has been obtained by reaction of [W(#eta#-C_5Me_5)Cl_4] with anthranilic acid [1,2-(NH_2)(CO_2H)C_6H_4]; the X-ray crystal structure shows a pseudo-octahedral geometry with a mer arrangement of chlorines and a symetrically chelating carboxylate group containing a pendant non-coordinated NH_2 group. Contrastingly, [ReCl(OEt)(PPh_3)_2(NC_6H_4CO_2)] (2), the product of the reaction between [ReOCl_3(PPH_3)_2] and anthranilic acid contains pseudooctahedral rhenium with a chelating imidobenzoate ligand and trans-phosphines which are mutually cis to the bent imido function [Re-N(1)-C(1)=143.5(3)deg]. The carboxylate group of the chelating liand is trans to a chloride with the remaining site (trans to the imido function) occupied by an ethoxide ligand.