Carbon dioxide, reaction with niobium

Reaction of NbC F with an alkali metal carbonate, M2CO3, yields carbon dioxide, C02, in an amount equivalent to that of a chemical compound forming at the first stage of the reaction. The general form of the reaction between niobium dioxyfluoride and an alkali metal carbonate, M2C03, is ... 

The reaction of Uganded nickel , molybdenumand niobium complexes with carbon dioxide produces [2+1] cycloadducts 11, which are relatively stable compounds. 

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