Catalytic formation of carbamates and cyclic carbonates by copper complex of 2,5,19,22-tetraaza[6,6](1,1′)ferrocenophane-1,5-diene X-ray crystal structure of [Cu(1)]PF6

Article abstract of DOI:10.1016/S0022-328X(97)00366-5

The reaction of [Cu(MeCN)₄]PF₆ with a ferrocene-containing tetraazamacrocycle 2,5,19,22-tetraaza[6,6](1,1)ferrocenophane-1,5-diene (1) gives the copper(I) complex of the type [Cu(1)]PF₆ (2) which crystallizes in the orthorhombic system: P2₁2₁2₁ (#19); a = 7.597(2) A, b = 14.805(5) A, c = 24.194(4) A; Z = 4; R = 0.080; R_w = 0,083. The geometry around the central metal is a distorted tetrahedron with two pairs of differing Cu-N bond length. This complex has demonstrated the excellent catalytic activity toward the formation of cyclic carbonates and carbamates in the presence of CO₂, giving almost quantitative product yields in most reactions that have been employed.