Reactions of Late First?Row Transition Metal (Fe?Zn) Dichlorides with a PGeP Pincer Germylene

The reactivity of the PGeP germylene 2,2’-bis(di-isopropylphosphanylmethyl)-5,5’-dimethyldipyrromethane-1,1’-diylgermanium(II), Ge(pyrmPiPr2)2CMe2, with late first-row transition metal (Fe-Zn) dichlorides has been investigated. All reactions led to pincer chloridogermyl complexes. FeCl2 and CoCl2 afforded paramagnetic square planar complexes formula [MCl{?3P,Ge,P-GeCl(pyrmPiPr2)2CMe2}] (M=Fe, Co). While iron complex maintained an intermediate spin state (S1; ?eff=3.0 ?B) over temperature range 50–380 K, effective magnetic moment cobalt varied linearly from 1.9 ?B at 10 K 3.6 380 indicating a crossover behavior that involves S1/2 (predominant T<180 K) S3/2 T>200 species. Both cobalt(II) species were detected by electron resonance T<20 K. reaction Ge(pyrmPiPr2)2CMe2 [NiCl2(dme)] (dme=dimethoxyethane) gave nickel(II) complex, [NiCl{?3P,Ge,P-GeCl(pyrmPiPr2)2CMe2}], whereas CuCl2 involved redox process rendered mixture germanium(IV) compound GeCl2(pyrmPiPr2)2CMe2 binuclear copper(I) [Cu2{?-?3P,Ge,P-GeCl(pyrmPiPr2)2CMe2}2], whose atoms are in tetrahedral environments. ZnCl2 derivative [ZnCl{?3P,Ge,P-GeCl(pyrmPiPr2)2CMe2}].