Exploring an Alternative Synthetic Pathway for the Total Synthesis of Rocaglamide
This thesis presents the exploration of a new synthetic pathway for the total synthesis of Rocaglamide incorporating a modified Interrupted Feist-Bénary reaction. This thesis focuses entirely on the key step of the synthetic pathway, the IFB reaction. A series of reactions were carried out using various nucleophiles and electrophiles with DABCO as the catalyst. The use of 2-hydroxycyclohexanone and 2-hydroxycyclopentaanone as electrophiles did not lead to the formation of any products. Reactions involving 1, 2- cyclopentadione as the electrophile did not yield any products mainly because 1,2-cyclopentadione broke down during the reaction due to its instability. 1,2-cyclohexanedione was reacted with several nucleophiles but only 5-(1,3-Dithiane)-1,3-cyclohexadione and 1,3-cyclohexanedione afforded products. The mass of the products from the reactions of 1,2-cyclohexandione with 5-(1,3-Dithiane)-1,3-cyclohexadione and 1,3-cyclohexanedione were 463.1969 g/mol and 357.2156 g/mol respectively. This suggested that two molecules of the nucleophile were reacting with one molecule of the electrophile. Further 1D and 2D NMR experiments were run on the products to obtain their structures. Further mechanistic studies were done to confirm the proposed mechanism. Running the reaction entirely at 0° C for three hours yielded the desired IFB product. This product was highly unstable and attempts to stabilize it proved futile. Further work can be done to stabilize this product and then incorporate it into the pathway.