O atom transfer reactions in some manganese and rhenium carbonyl compounds

Abstract

The compounds M(CO) 5Cl (M = Mn ( 1a); M = Re ( 1b)) undergo reaction with (CH 3) 3NO in CH 2Cl 2 to produce the series of anionic derivatives [M(CO) 4L 2] 1− (M = Mn ( 2a); M = Re ( 2b); L = Cl or N(CH 3) 3), [Mn(CO) 3Cl 3] 2− ( 3a) and [Mn 2(CO) 6(μ 2-Cl) 3] − ( 4a). These products have been identified from a comparison of their IR spectroscopic properties with authentic samples prepared by the direct reaction of Mn(CO) 5 Cl with Et 4 NCl. The PPN + salt of 4a has been characterized by X-ray crystallography. The compound crystallizes in the monoclinic space group P2 1/ n with the following cell dimensions; a = 9.5335(12), b = 15.6246(19) and c = 29.158(6) Å; β = 92.369(16)°. Further reactions of the intermediate manganese chloride complexes with PPNNO 2 in CH 2Cl 2 lead to the formation of the series of anionic derivatives [Mn(CO) 3Cl 2( NO 2)] 2− ( 5a), [Mn(CO) 3Cl( NO 2) 2] 2− ( 6a), [M(CO) 3( N O 2) 2( ON(O))] 2− ( 7a) and upon crystallization the trimer [Mn 3(CO) 6(μ 2- NO(O))4(μ 2-O(NO)) 2] 2− ( 8a). Reaction of Re(CO) 5Cl with PPNNO 2 in CH 2Cl 2 in the absence of Me 3NO yields the anionic species [Re(CO) 3( NO 2) 2( ONO)] 2− ( 7b), whereas in tetrahydrofuran under the same conditions the dianion [ fac-Re(CO) 3( ONO) 3] 2− ( 9b) is formed. Both compounds have been characterized as their PPN + salts by X-ray structure analysis. Compound 7b has been shown to exist in the monoclinic space group P2 1/ n with the following cell dimensions: a = 10.728(5), b = 13.231(3) and c = 23.383(7) Å; β = 100.58(3)°. Complex 9b crystallizes in the orthorhombic space group Pbca; the cell dimensions are a = 16.931(12), b = 19.593(9) and c = 19.971(13) Å.