R. G. Gerr

Interaction of Heteronuclear chromium-containing clusters with carboxalic acids. Molecular structure of the paramagnetic tetrahedral cluster Cp3Cr3(μ3-S)4Fe(OOCCMe3)

Abstract The reaction of (CpCrSCMe 3 ) 2 S and the adducts (CpCrSCMe 3 ) 2 S·ML (ML = Cr(CO) 5 , Mn 2 (CO) 9 and cluster (CpCrS) 2 (SCMe 3 )·Fe(CO) 3 (I) (containing CrCrFe metal chain) with benzoic acid gives the respective antiferromagnetic μ 3 -thio-bridged carboxylates Cr 2 MS(OOCPh) 6 (M = Cr(II), Mn(II), Fe(II)) (II–IV). On the other hand the reaction of I with the weaker trimethylacetic acid yields the tetrahedral cluster Cp 3 Cr 3 (μ 3 -S) 4 Fe(OOCCMe 3 ) (V) containing two unpaired electrons (μ eff = 2.81 BM). Crystal structure of V was solved by means of X-ray analysis (sp. gr. C2)c, a = 28.905(2), b = 9.563(2), c = 23.789(2) A, β = 131.84(3)°, V = 4902.8(4) A 3 Z = 4). In the metal tetrahedral skeleton Cr 3 Fe the average bond lengths CrCr and FeCr are 2.838(3) and 2.759(3) A respectively. The μ 3 -bridged sulfur atom locates over each tetrahedron face (the average CrS and FeS distances are 2.258(4) and 2.218(4) A respectively). Each chromium atom is combined to η 5 -C 5 H 5 ligand (the average CrC and CC distances are 2.224(20) and 1.391(30) A). The iron atom is bound to a terminal trimethylacetate group (FeO 1.896(10), O(1)C(1) 1.318(13), O(2)C(1) 1.252(21) A).

Molecular and crystal structure of 1-phenyl-3-methyl-5-(o-hydroxyphenyl)-1,2,4-triazole

A choice between the possible mechanisms of the recyclization of 4-oxo-1,3-benzoxazine salts due to reaction with phenylhydrazine was made based on the x-ray structure of 1-phenyl-3-methyl-5-(o-hydroxyphenyl)-1,2,4-triazole.