Friedel-Crafts reactions of the (-)-8-phenylmenthyl and (+ )-trans-2-(acumyl)
cycJohexyl aryl hydroxy acetates catalysed by trimethylsilyl triflate (TMSOTf)
and equivalents in the presence of electron rich heterocycles gave the expected
diarylacetates in high de 88%, via a planar cation.
The interaction of trifluoromethanesulfonic (triflic) acid (TfOH) with either bistrimethylsilyl
-acetamide (BSA) or -urea (BSU) can be used to generate
stoichiometric amounts of trimethylsilyl triflate (TMSOTf) "in situ" , the system can
be used efficiently to remove triflic acid from TMSOTf and to generate catalytic
amounts of TMSOTf from TfOH for use in a range of trimethylsilyl triflate
(TMSOTf) catalysed reactions.
Similarly the interaction of fluorosulfonic acid (FSA) with either bis-trimethylsilyl
-acetamide (BSA) or -urea (BSU) can be used to generate catalytic amounts of
trimethylsilylfluorosulfonate (TMSOFs) "in situ" for use in a wide range of reactions
as an alternative to trimethylsilyltriflate (TMSOTf)
Scandium(III) trifluoromethanesulfonate and copper(II) trifluoromethanesulfonate
can be used to catalyse aromatic alkylation with arylhydroxyacetates. Scandium(III)
trifluoromethanesulfonate also proved to be a recyclable catalyst for these reactions.
A number of Pictet-Spengler cyclisation reactions were also catalysed by
Scandium(III) trifluoromethanesulfonate and copper(II) trifluoromethanesulfonate.
Mannich reactions of a number of caJix[4jresorcinarene derivatives with (R)-(+)-amethylbenzylamine
under alkaline conditions lead to the formation of single
diastereomeric tetrakis(l,3-dihydrobenzoxazine) derivatives in high yields; the
reactions using the (S)-(-)-a-methylbenzylamine afford the enantiomers. The
products react with protic acids to afford equilibrium mixtures of diastereomers.
A Doctoral Thesis. Submitted in partial fulfillment of the requirements for the award of Doctor of Philosophy of Loughborough University.