Directive Effects in Substituted Ferrocenes

Morrison, Ian Gray (1962) Directive Effects in Substituted Ferrocenes. PhD thesis, University of Glasgow.

Abstract

This study describes some electrophilic substitutions of methylthio-, chloro-, and methoxy- ferrocene. The experiments were carried out in an attempt to determine the directive effects operative in these compounds. The aminomethylation of methylthioferrocene afforded the three (1,2; 1,1' and 1,3) isomeric dimethylaminomethyl-methylthioferrocenes, which were converted via their methiodides to the corresponding methyl-methylthioferrocenes These compounds were then converted to the corresponding thiocyanates, eg. 1-thiocyanato-1'-methylferrocene, and thence to the corresponding disulphides, e.g. di-(1'-methyIferrocenyl)disulphide. An independent synthesis of di-(1'-methyIferrocenyl)disulphide from 1-carboxyferrocene-1'-sulphonic acid provided conclusive identification of this compound. The site reactivities, as determined from the weights of isomeric methyl-methylthioferrocenes isolated, indicate that the methylthio group is activating in nature. Chloroferrocene was found to acetylate exclusively in the unsubstituted ring, thus demonstrating the deactivating effect of the chloro substituent A new route to ferrocenylboronic acid via ferrocenyl-boronyl dichloride, greatly simplified the preparation of methoxyferrocene. When methoxyferrocene was subjected to Friedel-Crafts acetylation, a mixture of the three (1,2; 1,1' and 1,3) isomeric acetyl-methoxyferrocenes was isolated. These products were identified after reduction, as the corresponding ethyl-methoxyferrocenes. Site reactivities calculated from weights of isomeric ethyl= methoxyferrocenes, isolated from two different reduction methods (LiA1lH4-AlCl3 and Clemmensen reductions), provided unsatisfactory results. Aminomethylation of methoxyferrocene yielded a mixture of the three isomeric dimethylaminemethyl-methoxyferrocenes, which were identlfled, after reduction of the mixture of methiodides, as the corresponding methyl-methozyferrocenes. Site reactivities calculated from these reduction products showed the methoxy group to be activating in nature. The displacement of ferrocene substituents by protons was observed in certain reactions. Methylthio- and methoxy-ferrocene on treatment with aluminium trichloride, afforded not only ferrocene, but mixtures of the isomeric di(methyIthio)- and dimethoxy-ferrocenes. A similar treatment of chloroferrocene furnished only ferrocene.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Organic chemistry
• Date of Award: 1962
• Depositing User: Enlighten Team
• Unique ID: glathesis:1962-79465
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 05 Mar 2020 09:19
• Last Modified: 05 Mar 2020 09:19
• URI: https://theses.gla.ac.uk/id/eprint/79465