Derivatives of 1,3-bis-(2-hydroxyphenyl)-1,3-propanedione. An attempt to get more soluble heterotrinuclear complexes. Crystal structure of chromium tris-(1,3-bis-(2-hydroxyphenyl)-1,3-propanedionate)

The substitution of a hydrogen atom by other radicals has been achieved in 1,3-bis-(2-hydroxyphenyl) -1,3-propanedione (bhppH3) at the methinic carbon by reacting the Co(II) complex of this β- diketone with different electrophiles. In most of the cases the reaction proceeded further to yield the corresponding flavones. To have a better range of solvents to carry on these reactions the Fe3+ and Cr3+-bhppH3 complexes were synthesized. The TLC of the solids obtained indicated the existence of several M-bhppH3 complexes. The crystal structure of the Cr(bhppH2)3·0.5toluene is reported. Triclinic,P1, a = 14.282(3), b = 14.127(3), c= 12.240(2) Å, α = 123.24(3), β = 94.72(2), γ = 90.87- (2)°, V=2053(1) Å3, Z=2. Reaction of Fe- (bhppH2)3 with NBS yielded, after working up with SCN-, mostly dibrominated derivatives. Reaction of 2-diphenylmethyl-1,3-(2-hydroxyphenyl)-1,3- propanedione (dpmbhppH3) with M(AcO)2·xH2O in pyridine (M=Ni, Co) yielded M3(dpmbhpp)2· 6py. The introduction of the R group at the methinic carbon lowers its reactivity. © 1987.