UBC Theses and Dissertations
The synthesis of a compound suitable for the elaboration of the C-ring of nitiol Woo, Jacqueline C. S.
Compound 34 was a synthetic target suitable for the elaboration to the C-ring of nitiol (1), and was synthesized over six steps from the known alcohol 39. A convenient method for the synthesis of N-methoxy-N-methyl amides was also developed. Ester 38 was synthesized from alcohol 39, and was subjected to an Ireland-Claisen rearrangement to give acid 37. This step established the stereochemical relationship of the substituents of 34. Carboxylic acid 37 was converted to amide 51 by the use of triethylamine, methanesulfonyl chloride, and N,O-dimethylhydroxylamine. This method was also used in the synthesis of seven other examples of N-methoxy-N-methyl amides with good to excellent yields (61-84 %). Amide 51 was converted to vinyl ketone 36, and subsequent ring-closing metathesis afforded cyclopentenone 35 with a cis/trans ratio of 12:1. A 1,4-hydride reduction of cyclopentenone 35 and the subsequent trapping of the enolate as a trifluoromethanesulfonate gave 34 with a cis/trans ratio of 9:1. [Chemical Diagrams]
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