Synthesis and Physico‐Chemical Studies of New Types of Heteroleptic Isopropoxometallates of Chromium(III)

Abstract

Novel heterobimetallic isopropoxides of chromium(III) of the types: {CrCl₂[Al(OPr‐i)₄](THF)₂} (1a), {CrCl[Al(OPr‐i)₄]₂(THF)} (1b), {CrCl[Ga(OPr‐i)₄]₂(THF)} (1c), {CrCl[Nb(OPr‐i)₆]₂(THF)} (1d), {CrCl₂[Zr₂(OPr‐i)₉]} (1e), {CrCl₂[Sn₂(OPr‐i)₉]} (1f), and {CrCl[Zr₂(OPr‐i)₉]₂} (1g) have been prepared by the reactions of CrCl₃·3THF in the required molar ratios with a variety of potassium alkoxometallates in tetrahydrofuran (THF) or benzene. Heteropenta‐and hexanuclear complexes, {Cr[Zr₂(OPr‐i)₉]₂[Al(OPr‐i)₄]} (2) and {Cr[Zr₂(OPr‐i)₉]₂[Al(OPr‐i)₄]} (3), were obtained by the interactions of a chloro(isopropoxometallato)chromium(III) complex with an appropriate potassium isopropoxometallate in the desired molar ratios in benzene. Elemental analyses and molecular weight measurements of these interesting coordination compounds are consistent with the formulations depicted above. Electronic spectroscopic and magnetic susceptibility data support an octahedral environment around chromium(III).

Keywords:

• Chromium(III)
• Isopropoxometallates
• Synthesis
• Electronic spectra

Acknowledgments

A.S. thanks the University Grants Commission, New Delhi, for the financial support under the Emeritus Scientist Scheme. R.A. is grateful to the State Government of Rajasthan and the Department of Chemistry, University of Rajasthan, for a fellowship under the Special Assistance Programme. S.M. is indebted to the Council of Scientific and Industrial Research (CSIR), New Delhi, for a Senior Research Fellowship.