• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • No language data
  • Tagged with
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Ferrocenylketones and the stabilisation of their thio analogues

Bell, William January 1991 (has links)
An effective method for the stabilization of otherwise unstable thiones is their complexation to M(CO)5 (M= Cr, Mo, W). This complexation led to a very stable material of composition C22H14CrFeO5S, whose crystals are triclinic, space group PI (No. 2) with a=9.058(7), b=10.040(7), c=12.568(8) Å, α=113.70(5), β=93.42(6), γ=95.25(6)° and Z=2. The structure was refined from diffractometer data to an R value of 0.0049. The structure was found to be that of pentacarbonyl(thiobenzoylferrocene-S) chromium, in which the Cr(CO)5 fragment is bonded to the sulphur atom of the thioacyl ferrocene. The photodegradation product was found to have a composition of C17H14FeO, crystals were monoclinic, space group P21 (No. 14) with a=6.09(6), b=15.145(7), c=14.263(4)Å, β=105.91(1)° and Z=4. The structure was refined to an R value of 0.059, and was found to be benzoylferrocene. 1,1'-Dibenzoylferrocene reacts with tetraphosphorus decasulphide to yield, in addition to the expected 1,1'-bis(thiobenzoyl)ferrocene, a minor, yellow by-product of composition C24H18FeS3, whose crystals are monoclinic, space group P21/n with a=11.769(3), b=11.750(4), c=14.835(2) Å, β=98.63(1)°, and Z=4: the structure was found to be that of 1,4-diphenyl-1,4-epithio-2,3-dithia[4](1,1')-ferrocenophane in which the two rings of the ferrocene nucleus are spanned by a 1,2,4-trithiolane ring. Whereas the reaction of ferrocene with a stoichiometric quantity of Me3CCOCl/AICI3 provides the monoacylated product in 87% yield, the use of excess of the acylation reagent leads to simultaneous acylation and alkylation, two products of which have been isolated and characterised by 1H and 13C NMR, spectroscopy as 1,1/3-tri-t- butyl-3'-(2,2-dimethylpropionyl) ferrocene, [C5H3(CMe3)2] Fe [C5H3(CMe3)COCMe3)] and 1,1'-di-t-butyl-3,3'-bis(2,2-dimethylpropiony)ferrocene, [C5H3(CMe3)(COCMe3)]2Fe . Flash Vacuum Pyrolysis of a number of ferrocenes have been carried out and the mono and diacyl ferrocenes were found to display a high degree of thermal stability, most of these being recovered in almost quantitative yields at furnace temperatures up to 700 °C. Ferrocenecarboxaldoxime acetate was found to yield cyanoferrocene and acetic acid in a clean reaction in which the cyanoferrocene was uncontaminated with the acetic acid. Crystals of the low melting form of ferrocenecarboxaldoxime, (C5H5)Fe(C5H4CH = NOH) are monoclinic, space-group C2/c with a= 26.512(6), b = 12.798 (4), c = 12.855 (2)Å, β = 114.37 (1)°, and Z = 16. The structure was refined from diffractometer data to an R value of 0.054. There are two molecular sites in the asymmetric unit, and both sites contain a disordered mixture of E and Z geometrical isomers. There are no close contacts between the iron atom and the hydroxyl group of the oxime substituent, but rather there is extensive intermolecular hydrogen bonding.

Page generated in 0.0392 seconds