Abstract
Abstract The Diels-Alder cycloaddition reaction of □-diethylphosphonyl cyclohex-2-en-1-ones 34 and 37 and subsequent transformations of resulting cycloadducts are described in this thesis. Part one dscribes the Diels-Alder cycloaddition reaction of enones 34 and 37, which were synthesized using known procedures. Enones 34 and 37 were found to be effective dienophiles, giving the expected cycloadducts in good to excellent yields and within a reasonable period of time. The reaction was found to follow the ortho- and para- rules and gave the endo-to-ketone product. Of all the Lewis acids investigated, tin chloride was deemed to be the most effective Lewis acid. Part two describes the use of lithium naphthalenide as an efficacious reducing agent in the removal of the angular alkyl phosphonyl group in the above-formed cycloadducts. The resulting enolate was then trapped with a variety of alkylating agents, giving in all cases, a cis-ring junction. Part three describes an interesting use of the phosphonate containing cycloadducts mentioned above in a Wittig type reaction. The above- formed cycloadducts were first treated with a variety of Grignard reagents. The resulting 1,2-adducts 68 and 69 were then treated with potassium hydride in the presence of 18-crown-6 to give various rearrangement products 70 and 71.