Adam Piórko

Metal-marked steroids of the estrane group from the reaction of steroidal functional groups with arene-iron(Cp) complexes

Abstract Reaction of (η 6 -p-chlorotoluene)(η 5 -cyclopentadienyliron)(II) hexafluorophosphate with the phenolic hydroxy group of estrane steroids, under mild conditions, leads to the formation of 3-O-p-tolyle thers of steroids, with an iron(Cp) marker. Employing this reaction, estrone, estradiol and 17-α-ethynylestradiol have been marked in high yield. The utility of such marked steroids in metalloimmunoassay has been examined. Steroids marked in such a way show no measurable affinity for the estradiol receptor. The 3-O-p-tolyestrone complex is stable at room temperature for 24 h, in water solutions of buffers at pH 2.0 and 7.41, as well as in a THF solution in the presence of pyrrolidine. The marker fragment may be removed at room temperature upon the action of pyrrolidine in a 1:1 water-THF solution or potassium hydroxide in water for 24 h with the efficient recovery of steroid. Treatment of marked estrone with an excess of potassium t-butoxide leads to demetallation and the formation of 3-O-p-tolylestrone. Attempts to mark estrone and testosterone via the carbonyl group or estradiol and cholesterol via the secondary hydroxyl group, under mild conditions, have been unsuccesful.

Cyclopentadienyliron-mediated introduction of functionalized alkyl or alkynyl groups to arenes in an addition—demetallation sequence

Abstract Nitromethyl, cyanomethyl, and phenylethynyl anions add selectively ortho to arenes containing electron-witdrawing groups and complexed with cyclopentadienyliron. Under similar reaction conditions anions such as alkyl, dichloromethyl and trichloromethyl add in a non-selective way. Addition of the trichloromethyl anion is thermodynamically controlled at extended reaction times and, due to the size of the anion, the meta addition product is favoured. Demetallation of adducts leads to ortho -nitromethylated, cyanomethylated or phenylethynylated arenes, respectively. With symmetrical arene complexes the addition—demetallation sequence leads to the introduction of a trichloromethyl group into the arene ring, yielding a single product. A one-pot procedure for trichloromethylation of dialkylarenes starting from appropriate cyclopentadienyliron complexes gives β-trichloromethylated dialkylarenes in a good yield.

Hexafluorophosphate salts of cyclopentadienyliron(II) complexes of dibenzodioxin and 1-methyldibenzodioxin

The structures of (η 5 -cyclopentadienyl)[(1,2,3,4,4a,10aη 6 )-dibenzo[b,e][1,4]dioxin]iron(II) hexafluorophosphate (1), [Fe(C 5 H 5 )(C 12 H 8 O 2 )]PF 6 , and (η 5 -cyclopentadienyl)[(1,2,3,4,4a,10a-η 6 )-1-methyldibenzo[b,e][1,4]-dioxin]iron(II) hexafluorophosphate diethyl ether solvate (2), [Fe(C 5 H 5 )(C 13 H 10 O 2 )]PF 6 .0.5C 4 H 10 O, have been determined. The dihedral angle between the outer rings of dibenzodioxin was found to be 175.8 (2) in (1) and 177.55 (19)° in (2). The planes of the coordinated arene and cyclopentadienyl (Cp) rings are nearly parallel for both complexes. The Fe atom is centered above the Cp ring while Fe-C distances involving the quatenary C atoms of the coordinated arene rings are slightly longer than those involving the other aromatic C atoms, particularly for complex (2). In the central dioxin ring of both complexes, O-C bonds of the coordinated ring are shorter than those of the uncoordinated ring

[(5a,6,7,8,9,9a-η6)-[1,4]Benzodioxino[2,3-b]pyridine](η5-cyclopentadienyl)iron(II) hexafluorophosphate

The structure of [(5a,6,7,8,9,9a-η 6 )-[1,4]benzodioxino[2,3-b]pyridine](η 5 -cyclopentadienyl)iron(II) hexafluorophosphate, [Fe(C 5 H 5 )(C 11 H 7 NO 2 )]PF 6 , has been studied. The dihedral angle between the benzene and pyridine rings of the ligand system is 177.4 (3) o ; the benzene and cyclopentadienyl rings are nearly parallel [dihedral angle 1.3 (4) o ]. The Fe atom is closer to the benzene ring [1.542 (4) A] than to the cyclopentadienyl (Cp) ring [1.652 (5) A] and it is located within the fold of the heterocyclic ligand

Structure of (η5-cyclopentadienyl)(η6-thianthrene)iron(II) hexafluorophosphate

[Fe(CsI-I5)(C,2HsS2)][PFr] (I), M, = 482.22, monoclinic, P2Jc, a= 14.194 (3), b = 9.617 (2), c = 25-971 (5) A, /3 = 100.31 (2) °, V = 3488 (1) A3, Z = 8 (two molecules per a s y m m e t r i c u n i t ) , Dx = 1.836 g cm -3, Mo Kte (A = 0.70169 A), /z = 12-429 cm -1, F(000) = 1936, T = 163 K. Blockmatrix least-squares refinement of (I) converged to R = 0-044 and wR = 0.040 using 3785 reflections with I > 3g(/). The dihedral angles of the two molecules in the asymmetric unit are different. In molecule A, the FeCp moiety (Cp = cyclopentadiene) is inside the fold with a dihedral angle of 143.1 (2) °, whereas in molecule B, the FeCp moiety is located outside the fold with a dihedral angle of 136.3 (2) °. Introduction. In a continuation of our study on the synthesis, structure and properties of the FeCp complexes of tricyclic heterocycles, the structure of (I)

[η6-1-Chloro-2-(pyrrolidin-1-yl)benzene](η5-cyclopentadienyl)iron(II) hexafluoridophosphate and (η5-cyclopentadienyl){2-[η6-2-(pyrrolidin-1-yl)phenyl]phenol}iron(II) hexafluoridophosphate.

In the complex salt [η(6)-1-chloro-2-(pyrrolidin-1-yl)benzene](η(5)-cyclopentadienyl)iron(II) hexafluoridophosphate, [Fe(C(5)H(5))(C(10)H(12)ClN)]PF(6), (I), the complexed cyclopentadienyl and benzene rings are almost parallel, with a dihedral angle between their planes of 2.3 (3)°. In a related complex salt, (η(5)-cyclopentadienyl){2-[η(6)-2-(pyrrolidin-1-yl)phenyl]phenol}iron(II) hexafluoridophosphate, [Fe(C(5)H(5))(C(16)H(17)NO)]PF(6), (II), the analogous angle is 5.4 (1)°. In both complexes, the aromatic C atom bound to the pyrrolidine N atom is located out of the plane defined by the remaining five ring C atoms. The dihedral angles between the plane of these five ring atoms and a plane defined by the N-bound aromatic C atom and two neighboring C atoms are 9.7 (8) and 5.6 (2)° for (I) and (II), respectively.

(η5-Cyclo­penta­dien­yl)[(1,2,3,4,4a,12a-η)-naphtho­[2,3-b][1,4]benzodioxine]iron(II) hexa­fluoridophosphate

At 296 (2) K, both complexed rings in the iron(II) complex cation of the title salt, [Fe(C5H5)(C16H10O2)]PF6, are almost parallel [dihedral angle between planes = 2.4 (3)°]. The quaternary C atoms of the complexed arene ring are located at the longest distance from the Fe atom, with Fe—C distances of 2.112 (4) and 2.105 (3) Å, which are slightly longer than the average Fe—C distance for this ring (2.083 Å). The Fe ion is located 1.660 (1) and 1.543 (1) Å, respectively, from the cyclopentadienyl and the complexed arene ring.

(η5-Cyclo­penta­dien­yl)(η6-1,2-dipyrrolidin-1-ylbenzene)iron(II) hexa­fluoridophosphate

Both complexed rings in the iron(II) complex cation of the title salt, [Fe(C5H5)(C14H20N2)]PF6, are almost parallel [dihedral angle between planes = 5.34 (13)°]. Among the C atoms of the complexed arene ring, the quaternary C atoms are located at the longest, albeit unequal, distances from the Fe atom [2.252 (2) and 2.168 (2) Å].

(η5-Cyclopentadienyl)[(1,2,3,4,4a,10a-η)-1-methylthianthrene]iron(II) hexafluoridophosphate acetone 0.33-solvate

The title complex salt, [Fe(C(5)H(5))(C(13)H(10)S(2))]PF(6).0.33C(3)H(6)O, obtained from an acetone-diethyl ether-dichloromethane mixture at 280 (2) K, has three cationic molecules (A-C), three hexafluoridophosphate counter-anions and one acetone solvent molecule in the asymmetric unit. Two of the three cations contain FeCp (Cp is cyclopentadienyl) inside the fold of the heterocycle. The dihedral angles between the planes of the external (complexed and uncomplexed) benzene rings in the thianthrene molecule are 146.5 (2) degrees for FeCp-out-of-fold molecule A, and 139.0 (3) and 142.5 (2) degrees for the two FeCp-in-fold molecules B and C, respectively. The complexed Cp and benzene rings in each molecule are almost parallel, with a dihedral angle between the planes of 0.2 (5) degrees for molecule A, 2.8 (5) degrees for B, and 2.19 (4) and 6.86 (6) degrees for the disordered Cp ring in C.

(η5-Cyclo­penta­dien­yl)[η6-diethyl eth­yl(phen­yl)malonate]iron(II) hexa­fluorido­phosphate

At 223 (2) K, the complexed rings in the iron(II) complex cation of the title salt, [Fe(C5H5)(C15H20O4)]PF6, are almost parallel [dihedral angle between planes = 4.10 (14)°]. Among the C atoms of the complexed arene ring, the quaternary C atom is located at the longest distance from the Fe atom. The F atoms of the PF6 − anion were found to be equally disordered over two sites.