ORGANOMETALLIC PHOTOCHEMISTRY IN SUPERCRITICAL FLUIDS - REACTIONS OF CYCLOPENTADIENYL CARBONYL AND PHOSPHINE CARBONYL-COMPLEXES OF MANGANESE WITH DINITROGEN

UV photolysis has been used to generate dinitrogen compounds by substi tution of CO groups by N-2 in supercritical fluid solvents (scXe, scCO (2) and scC(2)H(6)) containing high pressures of N-2. Compounds includ e Cp'Mn(CO)(2)L (Cp' = C(5)H(4)Me; L = PMe(3-x)Ph(x), x = 0 to 3). A s emi-quantitative comparison of the photolysis of CpMn(CO)(3) (Cp* = C (5)Me(5)) and N-2 in scXe and scCO(2) indicates that there is little d ifference between the effectiveness of the photolysis in these two sup ercritical solvents. The Timney Ligand Effect approach is used to rati onalise the fact that some of the v(C-O) and v(N-N) bands of CpMn(CO) (2)(N-2) and CpMn(CO)(N-2)(2) are nearly coincident.