Dipyrromethane-Based PGeP Pincer Methylgermyl and Methoxidogermyl Nickel and Palladium Complexes

The dipyrromethane-based chloridogermyl complexes [MCl{kappa P-3,Ge,P-GeCl(pyrmP(i)Pr(2))(2)CMe2}] (1(M); M=Ni, Pd; (pyrmP(i)Pr(2))(2)CMe2=5,5'-dimethyl-2,2'-bis(di-isopropylphosphanylmethyl)dipyrromethane-1,1'-diyl) reacted with one or more equivalents of LiOMe to give the monosubstituted complexes [MCl{kappa P-3,Ge,P-Ge(OMe)(pyrmP(i)Pr(2))(2)CMe2}] (2(M-OMe); M=Ni, Pd). However, analogous treatments of complexes 1(M) with LiMe afforded the dimethyl complexes [MMe{kappa P-3,Ge,P-GeMe(pyrmP(i)Pr(2))(2)CMe2}] (3(M-Me); M=Ni, Pd). The monomethyl complexes [MCl{kappa P-3,Ge,P-GeMe(pyrmP(i)Pr(2))(2)CMe2}] (2(M-Me); M=Ni, Pd), which were identified as intermediates in the syntheses of 3(M-Me), were satisfactorily prepared by treating 3(M-Me) with HCl. The regioselectivities of these reactions have been rationalized with DFT calculations.

Automated summary

The interaction between the dipyrromethane-based chloridogermyl complexes and LiOMe or LiMe led to the synthesis of monosubstituted or dimethyl complexes. The regioselectivities of these reactions were rationalized with DFT calculations.